diff --git a/app/assets/javascripts/create_cluster/eks_cluster/components/eks_cluster_configuration_form.vue b/app/assets/javascripts/create_cluster/eks_cluster/components/eks_cluster_configuration_form.vue
index aefb31fe3d549..74b5a62f7548e 100644
--- a/app/assets/javascripts/create_cluster/eks_cluster/components/eks_cluster_configuration_form.vue
+++ b/app/assets/javascripts/create_cluster/eks_cluster/components/eks_cluster_configuration_form.vue
@@ -1,5 +1,5 @@
 <script>
-import { createNamespacedHelpers, mapState, mapActions } from 'vuex';
+import { createNamespacedHelpers, mapState, mapActions, mapGetters } from 'vuex';
 import { escape as esc } from 'lodash';
 import { GlFormInput, GlFormCheckbox } from '@gitlab/ui';
 import { sprintf, s__ } from '~/locale';
@@ -61,6 +61,7 @@ export default {
       'gitlabManagedCluster',
       'isCreatingCluster',
     ]),
+    ...mapGetters(['subnetValid']),
     ...mapRolesState({
       roles: 'items',
       isLoadingRoles: 'isLoadingItems',
@@ -119,7 +120,7 @@ export default {
         !this.selectedRegion ||
         !this.selectedKeyPair ||
         !this.selectedVpc ||
-        !this.selectedSubnet ||
+        !this.subnetValid ||
         !this.selectedRole ||
         !this.selectedSecurityGroup ||
         !this.selectedInstanceType ||
@@ -127,6 +128,9 @@ export default {
         this.isCreatingCluster
       );
     },
+    displaySubnetError() {
+      return Boolean(this.loadingSubnetsError) || this.selectedSubnet?.length === 1;
+    },
     createClusterButtonLabel() {
       return this.isCreatingCluster
         ? s__('ClusterIntegration|Creating Kubernetes cluster')
@@ -216,6 +220,13 @@ export default {
         false,
       );
     },
+    subnetValidationErrorText() {
+      if (this.loadingSubnetsError) {
+        return s__('ClusterIntegration|Could not load subnets for the selected VPC');
+      }
+
+      return s__('ClusterIntegration|You should select at least two subnets');
+    },
     securityGroupDropdownHelpText() {
       return sprintf(
         s__(
@@ -289,14 +300,14 @@ export default {
       this.setRegion({ region });
       this.setVpc({ vpc: null });
       this.setKeyPair({ keyPair: null });
-      this.setSubnet({ subnet: null });
+      this.setSubnet({ subnet: [] });
       this.setSecurityGroup({ securityGroup: null });
       this.fetchVpcs({ region });
       this.fetchKeyPairs({ region });
     },
     setVpcAndFetchSubnets(vpc) {
       this.setVpc({ vpc });
-      this.setSubnet({ subnet: null });
+      this.setSubnet({ subnet: [] });
       this.setSecurityGroup({ securityGroup: null });
       this.fetchSubnets({ vpc, region: this.selectedRegion });
       this.fetchSecurityGroups({ vpc, region: this.selectedRegion });
@@ -436,8 +447,8 @@ export default {
         :placeholder="s__('ClusterIntergation|Select a subnet')"
         :search-field-placeholder="s__('ClusterIntegration|Search subnets')"
         :empty-text="s__('ClusterIntegration|No subnet found')"
-        :has-errors="Boolean(loadingSubnetsError)"
-        :error-message="s__('ClusterIntegration|Could not load subnets for the selected VPC')"
+        :has-errors="displaySubnetError"
+        :error-message="subnetValidationErrorText"
         @input="setSubnet({ subnet: $event })"
       />
       <p class="form-text text-muted" v-html="subnetDropdownHelpText"></p>
diff --git a/app/assets/javascripts/create_cluster/eks_cluster/store/getters.js b/app/assets/javascripts/create_cluster/eks_cluster/store/getters.js
index e69de29bb2d1d..bbe4930c19134 100644
--- a/app/assets/javascripts/create_cluster/eks_cluster/store/getters.js
+++ b/app/assets/javascripts/create_cluster/eks_cluster/store/getters.js
@@ -0,0 +1,3 @@
+// eslint-disable-next-line import/prefer-default-export
+export const subnetValid = ({ selectedSubnet }) =>
+  Array.isArray(selectedSubnet) && selectedSubnet.length >= 2;
diff --git a/app/assets/javascripts/create_cluster/eks_cluster/store/state.js b/app/assets/javascripts/create_cluster/eks_cluster/store/state.js
index 20434dcce9844..d1337e7ea4ab2 100644
--- a/app/assets/javascripts/create_cluster/eks_cluster/store/state.js
+++ b/app/assets/javascripts/create_cluster/eks_cluster/store/state.js
@@ -21,7 +21,7 @@ export default () => ({
   selectedRole: '',
   selectedKeyPair: '',
   selectedVpc: '',
-  selectedSubnet: '',
+  selectedSubnet: [],
   selectedSecurityGroup: '',
   selectedInstanceType: 'm5.large',
   nodeCount: '3',
diff --git a/app/assets/javascripts/diffs/components/app.vue b/app/assets/javascripts/diffs/components/app.vue
index 77cd2afc10617..3ea2a2fbaee8b 100644
--- a/app/assets/javascripts/diffs/components/app.vue
+++ b/app/assets/javascripts/diffs/components/app.vue
@@ -50,6 +50,11 @@ export default {
       type: String,
       required: true,
     },
+    endpointCoverage: {
+      type: String,
+      required: false,
+      default: '',
+    },
     projectPath: {
       type: String,
       required: true,
@@ -169,6 +174,7 @@ export default {
       endpoint: this.endpoint,
       endpointMetadata: this.endpointMetadata,
       endpointBatch: this.endpointBatch,
+      endpointCoverage: this.endpointCoverage,
       projectPath: this.projectPath,
       dismissEndpoint: this.dismissEndpoint,
       showSuggestPopover: this.showSuggestPopover,
@@ -218,6 +224,7 @@ export default {
       'fetchDiffFiles',
       'fetchDiffFilesMeta',
       'fetchDiffFilesBatch',
+      'fetchCoverageFiles',
       'startRenderDiffsQueue',
       'assignDiscussionsToDiff',
       'setHighlightedRow',
@@ -292,6 +299,10 @@ export default {
           });
       }
 
+      if (this.endpointCoverage) {
+        this.fetchCoverageFiles();
+      }
+
       if (!this.isNotesFetched) {
         eventHub.$emit('fetchNotesData');
       }
diff --git a/app/assets/javascripts/diffs/components/diff_expansion_cell.vue b/app/assets/javascripts/diffs/components/diff_expansion_cell.vue
index 4eae2e09c08dd..46ed76450c475 100644
--- a/app/assets/javascripts/diffs/components/diff_expansion_cell.vue
+++ b/app/assets/javascripts/diffs/components/diff_expansion_cell.vue
@@ -54,7 +54,7 @@ export default {
     colspan: {
       type: Number,
       required: false,
-      default: 3,
+      default: 4,
     },
   },
   computed: {
diff --git a/app/assets/javascripts/diffs/components/inline_diff_comment_row.vue b/app/assets/javascripts/diffs/components/inline_diff_comment_row.vue
index a06dbd70ac56b..87f0396cf72c5 100644
--- a/app/assets/javascripts/diffs/components/inline_diff_comment_row.vue
+++ b/app/assets/javascripts/diffs/components/inline_diff_comment_row.vue
@@ -51,7 +51,7 @@ export default {
 
 <template>
   <tr v-if="shouldRender" :class="className" class="notes_holder">
-    <td class="notes-content" colspan="3">
+    <td class="notes-content" colspan="4">
       <div class="content">
         <diff-discussions
           v-if="line.discussions.length"
diff --git a/app/assets/javascripts/diffs/components/inline_diff_table_row.vue b/app/assets/javascripts/diffs/components/inline_diff_table_row.vue
index 55a8df43c62fe..bd99fcb71b8b5 100644
--- a/app/assets/javascripts/diffs/components/inline_diff_table_row.vue
+++ b/app/assets/javascripts/diffs/components/inline_diff_table_row.vue
@@ -1,5 +1,6 @@
 <script>
-import { mapActions, mapState } from 'vuex';
+import { mapActions, mapGetters, mapState } from 'vuex';
+import { GlTooltipDirective } from '@gitlab/ui';
 import DiffTableCell from './diff_table_cell.vue';
 import {
   MATCH_LINE_TYPE,
@@ -15,11 +16,18 @@ export default {
   components: {
     DiffTableCell,
   },
+  directives: {
+    GlTooltip: GlTooltipDirective,
+  },
   props: {
     fileHash: {
       type: String,
       required: true,
     },
+    filePath: {
+      type: String,
+      required: true,
+    },
     contextLinesPath: {
       type: String,
       required: true,
@@ -40,6 +48,7 @@ export default {
     };
   },
   computed: {
+    ...mapGetters('diffs', ['fileLineCoverage']),
     ...mapState({
       isHighlighted(state) {
         return this.line.line_code !== null && this.line.line_code === state.diffs.highlightedRow;
@@ -62,6 +71,9 @@ export default {
     isMatchLine() {
       return this.line.type === MATCH_LINE_TYPE;
     },
+    coverageState() {
+      return this.fileLineCoverage(this.filePath, this.line.new_line);
+    },
   },
   created() {
     this.newLineType = NEW_LINE_TYPE;
@@ -113,6 +125,12 @@ export default {
       :is-highlighted="isHighlighted"
       class="diff-line-num new_line qa-new-diff-line"
     />
+    <td
+      v-gl-tooltip.hover
+      :title="coverageState.text"
+      :class="[line.type, coverageState.class, { hll: isHighlighted }]"
+      class="line-coverage"
+    ></td>
     <td
       :class="[
         line.type,
@@ -120,7 +138,7 @@ export default {
           hll: isHighlighted,
         },
       ]"
-      class="line_content"
+      class="line_content with-coverage"
       v-html="line.rich_text"
     ></td>
   </tr>
diff --git a/app/assets/javascripts/diffs/components/inline_diff_view.vue b/app/assets/javascripts/diffs/components/inline_diff_view.vue
index 1eb17588376f7..8b25cdc2887c7 100644
--- a/app/assets/javascripts/diffs/components/inline_diff_view.vue
+++ b/app/assets/javascripts/diffs/components/inline_diff_view.vue
@@ -48,6 +48,7 @@ export default {
     <colgroup>
       <col style="width: 50px;" />
       <col style="width: 50px;" />
+      <col style="width: 8px;" />
       <col />
     </colgroup>
     <tbody>
@@ -63,6 +64,7 @@ export default {
         <inline-diff-table-row
           :key="`${line.line_code || index}`"
           :file-hash="diffFile.file_hash"
+          :file-path="diffFile.file_path"
           :context-lines-path="diffFile.context_lines_path"
           :line="line"
           :is-bottom="index + 1 === diffLinesLength"
diff --git a/app/assets/javascripts/diffs/components/parallel_diff_comment_row.vue b/app/assets/javascripts/diffs/components/parallel_diff_comment_row.vue
index 65b41b0e45674..b525490f7cc5a 100644
--- a/app/assets/javascripts/diffs/components/parallel_diff_comment_row.vue
+++ b/app/assets/javascripts/diffs/components/parallel_diff_comment_row.vue
@@ -122,7 +122,7 @@ export default {
 
 <template>
   <tr v-if="shouldRender" :class="className" class="notes_holder">
-    <td class="notes-content parallel old" colspan="2">
+    <td class="notes-content parallel old" colspan="3">
       <div v-if="shouldRenderDiscussionsOnLeft" class="content">
         <diff-discussions
           :discussions="line.left.discussions"
@@ -147,7 +147,7 @@ export default {
         </template>
       </diff-discussion-reply>
     </td>
-    <td class="notes-content parallel new" colspan="2">
+    <td class="notes-content parallel new" colspan="3">
       <div v-if="shouldRenderDiscussionsOnRight" class="content">
         <diff-discussions
           :discussions="line.right.discussions"
diff --git a/app/assets/javascripts/diffs/components/parallel_diff_expansion_row.vue b/app/assets/javascripts/diffs/components/parallel_diff_expansion_row.vue
index c1b30eab199b1..0a80107ced4c5 100644
--- a/app/assets/javascripts/diffs/components/parallel_diff_expansion_row.vue
+++ b/app/assets/javascripts/diffs/components/parallel_diff_expansion_row.vue
@@ -49,7 +49,7 @@ export default {
         :line="line.left"
         :is-top="isTop"
         :is-bottom="isBottom"
-        :colspan="4"
+        :colspan="6"
       />
     </template>
   </tr>
diff --git a/app/assets/javascripts/diffs/components/parallel_diff_table_row.vue b/app/assets/javascripts/diffs/components/parallel_diff_table_row.vue
index 4c95d618b0f4a..83d803f42b14f 100644
--- a/app/assets/javascripts/diffs/components/parallel_diff_table_row.vue
+++ b/app/assets/javascripts/diffs/components/parallel_diff_table_row.vue
@@ -1,6 +1,7 @@
 <script>
-import { mapActions, mapState } from 'vuex';
+import { mapActions, mapGetters, mapState } from 'vuex';
 import $ from 'jquery';
+import { GlTooltipDirective } from '@gitlab/ui';
 import DiffTableCell from './diff_table_cell.vue';
 import {
   MATCH_LINE_TYPE,
@@ -18,11 +19,18 @@ export default {
   components: {
     DiffTableCell,
   },
+  directives: {
+    GlTooltip: GlTooltipDirective,
+  },
   props: {
     fileHash: {
       type: String,
       required: true,
     },
+    filePath: {
+      type: String,
+      required: true,
+    },
     contextLinesPath: {
       type: String,
       required: true,
@@ -44,6 +52,7 @@ export default {
     };
   },
   computed: {
+    ...mapGetters('diffs', ['fileLineCoverage']),
     ...mapState({
       isHighlighted(state) {
         const lineCode =
@@ -82,6 +91,9 @@ export default {
     isMatchLineRight() {
       return this.line.right && this.line.right.type === MATCH_LINE_TYPE;
     },
+    coverageState() {
+      return this.fileLineCoverage(this.filePath, this.line.right.new_line);
+    },
   },
   created() {
     this.newLineType = NEW_LINE_TYPE;
@@ -99,7 +111,7 @@ export default {
       const allCellsInHoveringRow = Array.from(e.currentTarget.children);
       const hoverIndex = allCellsInHoveringRow.indexOf(hoveringCell);
 
-      if (hoverIndex >= 2) {
+      if (hoverIndex >= 3) {
         this.isRightHover = isHover;
       } else {
         this.isLeftHover = isHover;
@@ -143,17 +155,19 @@ export default {
         line-position="left"
         class="diff-line-num old_line"
       />
+      <td :class="parallelViewLeftLineType" class="line-coverage left-side"></td>
       <td
         :id="line.left.line_code"
         :class="parallelViewLeftLineType"
-        class="line_content parallel left-side"
+        class="line_content with-coverage parallel left-side"
         @mousedown="handleParallelLineMouseDown"
         v-html="line.left.rich_text"
       ></td>
     </template>
     <template v-else>
       <td class="diff-line-num old_line empty-cell"></td>
-      <td class="line_content parallel left-side empty-cell"></td>
+      <td class="line-coverage left-side empty-cell"></td>
+      <td class="line_content with-coverage parallel left-side empty-cell"></td>
     </template>
     <template v-if="line.right && !isMatchLineRight">
       <diff-table-cell
@@ -169,6 +183,12 @@ export default {
         line-position="right"
         class="diff-line-num new_line"
       />
+      <td
+        v-gl-tooltip.hover
+        :title="coverageState.text"
+        :class="[line.right.type, coverageState.class, { hll: isHighlighted }]"
+        class="line-coverage right-side"
+      ></td>
       <td
         :id="line.right.line_code"
         :class="[
@@ -177,14 +197,15 @@ export default {
             hll: isHighlighted,
           },
         ]"
-        class="line_content parallel right-side"
+        class="line_content with-coverage parallel right-side"
         @mousedown="handleParallelLineMouseDown"
         v-html="line.right.rich_text"
       ></td>
     </template>
     <template v-else>
       <td class="diff-line-num old_line empty-cell"></td>
-      <td class="line_content parallel right-side empty-cell"></td>
+      <td class="line-coverage right-side empty-cell"></td>
+      <td class="line_content with-coverage parallel right-side empty-cell"></td>
     </template>
   </tr>
 </template>
diff --git a/app/assets/javascripts/diffs/components/parallel_diff_view.vue b/app/assets/javascripts/diffs/components/parallel_diff_view.vue
index 88baac092a177..d796aad9d06ba 100644
--- a/app/assets/javascripts/diffs/components/parallel_diff_view.vue
+++ b/app/assets/javascripts/diffs/components/parallel_diff_view.vue
@@ -47,8 +47,10 @@ export default {
   >
     <colgroup>
       <col style="width: 50px;" />
+      <col style="width: 8px;" />
       <col />
       <col style="width: 50px;" />
+      <col style="width: 8px;" />
       <col />
     </colgroup>
     <tbody>
@@ -64,6 +66,7 @@ export default {
         <parallel-diff-table-row
           :key="line.line_code"
           :file-hash="diffFile.file_hash"
+          :file-path="diffFile.file_path"
           :context-lines-path="diffFile.context_lines_path"
           :line="line"
           :is-bottom="index + 1 === diffLinesLength"
diff --git a/app/assets/javascripts/diffs/index.js b/app/assets/javascripts/diffs/index.js
index 375ac80021f13..ce48e36bfd7c5 100644
--- a/app/assets/javascripts/diffs/index.js
+++ b/app/assets/javascripts/diffs/index.js
@@ -69,6 +69,7 @@ export default function initDiffsApp(store) {
         endpoint: dataset.endpoint,
         endpointMetadata: dataset.endpointMetadata || '',
         endpointBatch: dataset.endpointBatch || '',
+        endpointCoverage: dataset.endpointCoverage || '',
         projectPath: dataset.projectPath,
         helpPagePath: dataset.helpPagePath,
         currentUser: JSON.parse(dataset.currentUserData) || {},
@@ -104,6 +105,7 @@ export default function initDiffsApp(store) {
           endpoint: this.endpoint,
           endpointMetadata: this.endpointMetadata,
           endpointBatch: this.endpointBatch,
+          endpointCoverage: this.endpointCoverage,
           currentUser: this.currentUser,
           projectPath: this.projectPath,
           helpPagePath: this.helpPagePath,
diff --git a/app/assets/javascripts/diffs/store/actions.js b/app/assets/javascripts/diffs/store/actions.js
index bd85105ccb4c7..18bbdf402eed1 100644
--- a/app/assets/javascripts/diffs/store/actions.js
+++ b/app/assets/javascripts/diffs/store/actions.js
@@ -1,8 +1,10 @@
 import Vue from 'vue';
 import Cookies from 'js-cookie';
+import Poll from '~/lib/utils/poll';
 import axios from '~/lib/utils/axios_utils';
+import httpStatusCodes from '~/lib/utils/http_status';
 import createFlash from '~/flash';
-import { s__ } from '~/locale';
+import { __, s__ } from '~/locale';
 import { handleLocationHash, historyPushState, scrollToElement } from '~/lib/utils/common_utils';
 import { mergeUrlParams, getLocationHash } from '~/lib/utils/url_utility';
 import TreeWorker from '../workers/tree_worker';
@@ -43,6 +45,7 @@ export const setBaseConfig = ({ commit }, options) => {
     endpoint,
     endpointMetadata,
     endpointBatch,
+    endpointCoverage,
     projectPath,
     dismissEndpoint,
     showSuggestPopover,
@@ -52,6 +55,7 @@ export const setBaseConfig = ({ commit }, options) => {
     endpoint,
     endpointMetadata,
     endpointBatch,
+    endpointCoverage,
     projectPath,
     dismissEndpoint,
     showSuggestPopover,
@@ -170,6 +174,26 @@ export const fetchDiffFilesMeta = ({ commit, state }) => {
     .catch(() => worker.terminate());
 };
 
+export const fetchCoverageFiles = ({ commit, state }) => {
+  const coveragePoll = new Poll({
+    resource: {
+      getCoverageReports: endpoint => axios.get(endpoint),
+    },
+    data: state.endpointCoverage,
+    method: 'getCoverageReports',
+    successCallback: ({ status, data }) => {
+      if (status === httpStatusCodes.OK) {
+        commit(types.SET_COVERAGE_DATA, data);
+
+        coveragePoll.stop();
+      }
+    },
+    errorCallback: () => createFlash(__('Something went wrong on our end. Please try again!')),
+  });
+
+  coveragePoll.makeRequest();
+};
+
 export const setHighlightedRow = ({ commit }, lineCode) => {
   const fileHash = lineCode.split('_')[0];
   commit(types.SET_HIGHLIGHTED_ROW, lineCode);
diff --git a/app/assets/javascripts/diffs/store/getters.js b/app/assets/javascripts/diffs/store/getters.js
index c4737090a708d..3898974638f84 100644
--- a/app/assets/javascripts/diffs/store/getters.js
+++ b/app/assets/javascripts/diffs/store/getters.js
@@ -1,3 +1,4 @@
+import { __, n__ } from '~/locale';
 import { PARALLEL_DIFF_VIEW_TYPE, INLINE_DIFF_VIEW_TYPE } from '../constants';
 
 export const isParallelView = state => state.diffViewType === PARALLEL_DIFF_VIEW_TYPE;
@@ -98,6 +99,29 @@ export const allBlobs = (state, getters) =>
 export const getCommentFormForDiffFile = state => fileHash =>
   state.commentForms.find(form => form.fileHash === fileHash);
 
+/**
+ * Returns the test coverage hits for a specific line of a given file
+ * @param {string} file
+ * @param {number} line
+ * @returns {number}
+ */
+export const fileLineCoverage = state => (file, line) => {
+  if (!state.coverageFiles.files) return {};
+  const fileCoverage = state.coverageFiles.files[file];
+  if (!fileCoverage) return {};
+  const lineCoverage = fileCoverage[String(line)];
+
+  if (lineCoverage === 0) {
+    return { text: __('No test coverage'), class: 'no-coverage' };
+  } else if (lineCoverage >= 0) {
+    return {
+      text: n__('Test coverage: %d hit', 'Test coverage: %d hits', lineCoverage),
+      class: 'coverage',
+    };
+  }
+  return {};
+};
+
 /**
  * Returns index of a currently selected diff in diffFiles
  * @returns {number}
diff --git a/app/assets/javascripts/diffs/store/modules/diff_state.js b/app/assets/javascripts/diffs/store/modules/diff_state.js
index 011cd24500a32..81f1506260c3f 100644
--- a/app/assets/javascripts/diffs/store/modules/diff_state.js
+++ b/app/assets/javascripts/diffs/store/modules/diff_state.js
@@ -17,6 +17,7 @@ export default () => ({
   commit: null,
   startVersion: null,
   diffFiles: [],
+  coverageFiles: {},
   mergeRequestDiffs: [],
   mergeRequestDiff: null,
   diffViewType: viewTypeFromQueryString || viewTypeFromCookie || defaultViewType,
diff --git a/app/assets/javascripts/diffs/store/mutation_types.js b/app/assets/javascripts/diffs/store/mutation_types.js
index 2097c8d365540..4436935c1ec29 100644
--- a/app/assets/javascripts/diffs/store/mutation_types.js
+++ b/app/assets/javascripts/diffs/store/mutation_types.js
@@ -5,6 +5,7 @@ export const SET_RETRIEVING_BATCHES = 'SET_RETRIEVING_BATCHES';
 export const SET_DIFF_DATA = 'SET_DIFF_DATA';
 export const SET_DIFF_DATA_BATCH = 'SET_DIFF_DATA_BATCH';
 export const SET_DIFF_VIEW_TYPE = 'SET_DIFF_VIEW_TYPE';
+export const SET_COVERAGE_DATA = 'SET_COVERAGE_DATA';
 export const SET_MERGE_REQUEST_DIFFS = 'SET_MERGE_REQUEST_DIFFS';
 export const TOGGLE_LINE_HAS_FORM = 'TOGGLE_LINE_HAS_FORM';
 export const ADD_CONTEXT_LINES = 'ADD_CONTEXT_LINES';
diff --git a/app/assets/javascripts/diffs/store/mutations.js b/app/assets/javascripts/diffs/store/mutations.js
index 086a7872a5d37..bb4c80b575982 100644
--- a/app/assets/javascripts/diffs/store/mutations.js
+++ b/app/assets/javascripts/diffs/store/mutations.js
@@ -16,6 +16,7 @@ export default {
       endpoint,
       endpointMetadata,
       endpointBatch,
+      endpointCoverage,
       projectPath,
       dismissEndpoint,
       showSuggestPopover,
@@ -25,6 +26,7 @@ export default {
       endpoint,
       endpointMetadata,
       endpointBatch,
+      endpointCoverage,
       projectPath,
       dismissEndpoint,
       showSuggestPopover,
@@ -69,6 +71,10 @@ export default {
     });
   },
 
+  [types.SET_COVERAGE_DATA](state, coverageFiles) {
+    Object.assign(state, { coverageFiles });
+  },
+
   [types.RENDER_FILE](state, file) {
     Object.assign(file, {
       renderIt: true,
diff --git a/app/assets/stylesheets/highlight/common.scss b/app/assets/stylesheets/highlight/common.scss
index bdeac7e97c0bc..31075b09b8360 100644
--- a/app/assets/stylesheets/highlight/common.scss
+++ b/app/assets/stylesheets/highlight/common.scss
@@ -29,3 +29,15 @@
     color: $link;
   }
 }
+
+@mixin line-coverage-border-color($coverage, $no-coverage) {
+  transition: border-left 0.1s ease-out;
+
+  &.coverage {
+    border-left: 3px solid $coverage;
+  }
+
+  &.no-coverage {
+    border-left: 3px solid $no-coverage;
+  }
+}
diff --git a/app/assets/stylesheets/highlight/themes/dark.scss b/app/assets/stylesheets/highlight/themes/dark.scss
index cbce0ba3f1ef2..5ab762a5104d1 100644
--- a/app/assets/stylesheets/highlight/themes/dark.scss
+++ b/app/assets/stylesheets/highlight/themes/dark.scss
@@ -24,6 +24,8 @@ $dark-pre-hll-bg: #373b41;
 $dark-hll-bg: #373b41;
 $dark-over-bg: #9f9ab5;
 $dark-expanded-bg: #3e3e3e;
+$dark-coverage: #b5bd68;
+$dark-no-coverage: #de935f;
 $dark-c: #969896;
 $dark-err: #c66;
 $dark-k: #b294bb;
@@ -124,12 +126,18 @@ $dark-il: #de935f;
     }
 
     td.diff-line-num.hll:not(.empty-cell),
+    td.line-coverage.hll:not(.empty-cell),
     td.line_content.hll:not(.empty-cell) {
       background-color: $dark-diff-not-empty-bg;
       border-color: darken($dark-diff-not-empty-bg, 15%);
     }
 
+    .line-coverage {
+      @include line-coverage-border-color($dark-coverage, $dark-no-coverage);
+    }
+
     .diff-line-num.new,
+    .line-coverage.new,
     .line_content.new {
       @include diff-background($dark-new-bg, $dark-new-idiff, $dark-border);
 
@@ -140,6 +148,7 @@ $dark-il: #de935f;
     }
 
     .diff-line-num.old,
+    .line-coverage.old,
     .line_content.old {
       @include diff-background($dark-old-bg, $dark-old-idiff, $dark-border);
 
@@ -168,6 +177,7 @@ $dark-il: #de935f;
     &:not(.diff-expanded) + .diff-expanded,
     &.diff-expanded + .line_holder:not(.diff-expanded) {
       > .diff-line-num,
+      > .line-coverage,
       > .line_content {
         border-top: 1px solid $black;
       }
@@ -175,6 +185,7 @@ $dark-il: #de935f;
 
     &.diff-expanded {
       > .diff-line-num,
+      > .line-coverage,
       > .line_content {
         background: $dark-expanded-bg;
         border-color: $dark-expanded-bg;
diff --git a/app/assets/stylesheets/highlight/themes/monokai.scss b/app/assets/stylesheets/highlight/themes/monokai.scss
index 1b61ffa37e362..348ef69cc4fa0 100644
--- a/app/assets/stylesheets/highlight/themes/monokai.scss
+++ b/app/assets/stylesheets/highlight/themes/monokai.scss
@@ -17,6 +17,8 @@ $monokai-diff-border: #808080;
 $monokai-highlight-bg: #ffe792;
 $monokai-over-bg: #9f9ab5;
 $monokai-expanded-bg: #3e3e3e;
+$monokai-coverage: #a6e22e;
+$monokai-no-coverage: #fd971f;
 
 $monokai-new-bg: rgba(166, 226, 46, 0.1);
 $monokai-new-idiff: rgba(166, 226, 46, 0.15);
@@ -124,12 +126,18 @@ $monokai-gi: #a6e22e;
     }
 
     td.diff-line-num.hll:not(.empty-cell),
+    td.line-coverage.hll:not(.empty-cell),
     td.line_content.hll:not(.empty-cell) {
       background-color: $monokai-line-empty-bg;
       border-color: $monokai-line-empty-border;
     }
 
+    .line-coverage {
+      @include line-coverage-border-color($monokai-coverage, $monokai-no-coverage);
+    }
+
     .diff-line-num.new,
+    .line-coverage.new,
     .line_content.new {
       @include diff-background($monokai-new-bg, $monokai-new-idiff, $monokai-diff-border);
 
@@ -140,6 +148,7 @@ $monokai-gi: #a6e22e;
     }
 
     .diff-line-num.old,
+    .line-coverage.old,
     .line_content.old {
       @include diff-background($monokai-old-bg, $monokai-old-idiff, $monokai-diff-border);
 
@@ -168,6 +177,7 @@ $monokai-gi: #a6e22e;
     &:not(.diff-expanded) + .diff-expanded,
     &.diff-expanded + .line_holder:not(.diff-expanded) {
       > .diff-line-num,
+      > .line-coverage,
       > .line_content {
         border-top: 1px solid $black;
       }
@@ -175,6 +185,7 @@ $monokai-gi: #a6e22e;
 
     &.diff-expanded {
       > .diff-line-num,
+      > .line-coverage,
       > .line_content {
         background: $monokai-expanded-bg;
         border-color: $monokai-expanded-bg;
diff --git a/app/assets/stylesheets/highlight/themes/none.scss b/app/assets/stylesheets/highlight/themes/none.scss
index a7ede266fb55f..c8ac3aa8305d3 100644
--- a/app/assets/stylesheets/highlight/themes/none.scss
+++ b/app/assets/stylesheets/highlight/themes/none.scss
@@ -51,6 +51,15 @@
       @include match-line;
     }
 
+    .line-coverage {
+      @include line-coverage-border-color($green-500, $orange-500);
+
+      &.old,
+      &.new {
+        background-color: $white-normal;
+      }
+    }
+
     .diff-line-num {
       &.old {
         a {
@@ -83,6 +92,7 @@
     &:not(.diff-expanded) + .diff-expanded,
     &.diff-expanded + .line_holder:not(.diff-expanded) {
       > .diff-line-num,
+      > .line-coverage,
       > .line_content {
         border-top: 1px solid $none-expanded-border;
       }
@@ -90,6 +100,7 @@
 
     &.diff-expanded {
       > .diff-line-num,
+      > .line-coverage,
       > .line_content {
         background: $none-expanded-bg;
         border-color: $none-expanded-bg;
diff --git a/app/assets/stylesheets/highlight/themes/solarized-dark.scss b/app/assets/stylesheets/highlight/themes/solarized-dark.scss
index 6569f3abc8b86..f5b36480f18c1 100644
--- a/app/assets/stylesheets/highlight/themes/solarized-dark.scss
+++ b/app/assets/stylesheets/highlight/themes/solarized-dark.scss
@@ -21,6 +21,8 @@ $solarized-dark-highlight: #094554;
 $solarized-dark-hll-bg: #174652;
 $solarized-dark-over-bg: #9f9ab5;
 $solarized-dark-expanded-bg: #010d10;
+$solarized-dark-coverage: #859900;
+$solarized-dark-no-coverage: #cb4b16;
 $solarized-dark-c: #586e75;
 $solarized-dark-err: #93a1a1;
 $solarized-dark-g: #93a1a1;
@@ -128,12 +130,18 @@ $solarized-dark-il: #2aa198;
     }
 
     td.diff-line-num.hll:not(.empty-cell),
+    td.line-coverage.hll:not(.empty-cell),
     td.line_content.hll:not(.empty-cell) {
       background-color: $solarized-dark-hll-bg;
       border-color: darken($solarized-dark-hll-bg, 15%);
     }
 
+    .line-coverage {
+      @include line-coverage-border-color($solarized-dark-coverage, $solarized-dark-no-coverage);
+    }
+
     .diff-line-num.new,
+    .line-coverage.new,
     .line_content.new {
       @include diff-background($solarized-dark-new-bg, $solarized-dark-new-idiff, $solarized-dark-border);
 
@@ -144,6 +152,7 @@ $solarized-dark-il: #2aa198;
     }
 
     .diff-line-num.old,
+    .line-coverage.old,
     .line_content.old {
       @include diff-background($solarized-dark-old-bg, $solarized-dark-old-idiff, $solarized-dark-border);
 
@@ -172,6 +181,7 @@ $solarized-dark-il: #2aa198;
     &:not(.diff-expanded) + .diff-expanded,
     &.diff-expanded + .line_holder:not(.diff-expanded) {
       > .diff-line-num,
+      > .line-coverage,
       > .line_content {
         border-top: 1px solid $black;
       }
@@ -179,6 +189,7 @@ $solarized-dark-il: #2aa198;
 
     &.diff-expanded {
       > .diff-line-num,
+      > .line-coverage,
       > .line_content {
         background: $solarized-dark-expanded-bg;
         border-color: $solarized-dark-expanded-bg;
diff --git a/app/assets/stylesheets/highlight/themes/solarized-light.scss b/app/assets/stylesheets/highlight/themes/solarized-light.scss
index 4e74a9ea50ab6..993370642c355 100644
--- a/app/assets/stylesheets/highlight/themes/solarized-light.scss
+++ b/app/assets/stylesheets/highlight/themes/solarized-light.scss
@@ -23,6 +23,8 @@ $solarized-light-hll-bg: #ddd8c5;
 $solarized-light-over-bg: #ded7fc;
 $solarized-light-expanded-border: #d2cdbd;
 $solarized-light-expanded-bg: #ece6d4;
+$solarized-light-coverage: #859900;
+$solarized-light-no-coverage: #cb4b16;
 $solarized-light-c: #93a1a1;
 $solarized-light-err: #586e75;
 $solarized-light-g: #586e75;
@@ -135,12 +137,18 @@ $solarized-light-il: #2aa198;
     }
 
     td.diff-line-num.hll:not(.empty-cell),
+    td.line-coverage.hll:not(.empty-cell),
     td.line_content.hll:not(.empty-cell) {
       background-color: $solarized-light-hll-bg;
       border-color: darken($solarized-light-hll-bg, 15%);
     }
 
+    .line-coverage {
+      @include line-coverage-border-color($solarized-light-coverage, $solarized-light-no-coverage);
+    }
+
     .diff-line-num.new,
+    .line-coverage.new,
     .line_content.new {
       @include diff-background($solarized-light-new-bg,
       $solarized-light-new-idiff, $solarized-light-border);
@@ -152,6 +160,7 @@ $solarized-light-il: #2aa198;
     }
 
     .diff-line-num.old,
+    .line-coverage.old,
     .line_content.old {
       @include diff-background($solarized-light-old-bg, $solarized-light-old-idiff, $solarized-light-border);
 
@@ -180,6 +189,7 @@ $solarized-light-il: #2aa198;
     &:not(.diff-expanded) + .diff-expanded,
     &.diff-expanded + .line_holder:not(.diff-expanded) {
       > .diff-line-num,
+      > .line-coverage,
       > .line_content {
         border-top: 1px solid $solarized-light-expanded-border;
       }
@@ -187,6 +197,7 @@ $solarized-light-il: #2aa198;
 
     &.diff-expanded {
       > .diff-line-num,
+      > .line-coverage,
       > .line_content {
         background: $solarized-light-expanded-bg;
         border-color: $solarized-light-expanded-bg;
diff --git a/app/assets/stylesheets/highlight/white_base.scss b/app/assets/stylesheets/highlight/white_base.scss
index 973f94c63aa92..d82a0794d29d5 100644
--- a/app/assets/stylesheets/highlight/white_base.scss
+++ b/app/assets/stylesheets/highlight/white_base.scss
@@ -151,6 +151,7 @@ pre.code,
   &:not(.diff-expanded) + .diff-expanded,
   &.diff-expanded + .line_holder:not(.diff-expanded) {
     > .diff-line-num,
+    > .line-coverage,
     > .line_content {
       border-top: 1px solid $white-expanded-border;
     }
@@ -158,6 +159,7 @@ pre.code,
 
   &.diff-expanded {
     > .diff-line-num,
+    > .line-coverage,
     > .line_content {
       background: $white-expanded-bg;
       border-color: $white-expanded-bg;
@@ -197,6 +199,22 @@ pre.code,
       background-color: $line-select-yellow;
     }
   }
+
+  .line-coverage {
+    @include line-coverage-border-color($green-500, $orange-500);
+
+    &.old {
+      background-color: $line-removed;
+    }
+
+    &.new {
+      background-color: $line-added;
+    }
+
+    &.hll:not(.empty-cell) {
+      background-color: $line-select-yellow;
+    }
+  }
 }
 
 // highlight line via anchor
diff --git a/app/assets/stylesheets/pages/diff.scss b/app/assets/stylesheets/pages/diff.scss
index 24c6fec064a8b..0c043e4f3fb5b 100644
--- a/app/assets/stylesheets/pages/diff.scss
+++ b/app/assets/stylesheets/pages/diff.scss
@@ -514,6 +514,10 @@ table.code {
           position: absolute;
           left: 0.5em;
         }
+
+        &.with-coverage::before {
+          left: 0;
+        }
       }
 
       &.new {
@@ -522,6 +526,10 @@ table.code {
           position: absolute;
           left: 0.5em;
         }
+
+        &.with-coverage::before {
+          left: 0;
+        }
       }
     }
   }
diff --git a/app/controllers/projects/merge_requests_controller.rb b/app/controllers/projects/merge_requests_controller.rb
index af185887a8caa..e87f1728cbbfb 100644
--- a/app/controllers/projects/merge_requests_controller.rb
+++ b/app/controllers/projects/merge_requests_controller.rb
@@ -14,7 +14,7 @@ class Projects::MergeRequestsController < Projects::MergeRequests::ApplicationCo
   skip_before_action :merge_request, only: [:index, :bulk_update]
   before_action :whitelist_query_limiting, only: [:assign_related_issues, :update]
   before_action :authorize_update_issuable!, only: [:close, :edit, :update, :remove_wip, :sort]
-  before_action :authorize_read_actual_head_pipeline!, only: [:test_reports, :exposed_artifacts]
+  before_action :authorize_read_actual_head_pipeline!, only: [:test_reports, :exposed_artifacts, :coverage_reports]
   before_action :set_issuables_index, only: [:index]
   before_action :authenticate_user!, only: [:assign_related_issues]
   before_action :check_user_can_push_to_source_branch!, only: [:rebase]
@@ -63,6 +63,7 @@ def show
         @issuable_sidebar = serializer.represent(@merge_request, serializer: 'sidebar')
         @current_user_data = UserSerializer.new(project: @project).represent(current_user, {}, MergeRequestUserEntity).to_json
         @show_whitespace_default = current_user.nil? || current_user.show_whitespace_in_diffs
+        @coverage_path = coverage_reports_project_merge_request_path(@project, @merge_request, format: :json) if @merge_request.has_coverage_reports?
 
         set_pipeline_variables
 
@@ -131,6 +132,14 @@ def test_reports
     reports_response(@merge_request.compare_test_reports)
   end
 
+  def coverage_reports
+    if @merge_request.has_coverage_reports?
+      reports_response(@merge_request.find_coverage_reports)
+    else
+      head :no_content
+    end
+  end
+
   def exposed_artifacts
     if @merge_request.has_exposed_artifacts?
       reports_response(@merge_request.find_exposed_artifacts)
diff --git a/app/models/ci/build.rb b/app/models/ci/build.rb
index 4762740ee2fd8..74a1985ca50c8 100644
--- a/app/models/ci/build.rb
+++ b/app/models/ci/build.rb
@@ -916,6 +916,14 @@ def collect_test_reports!(test_reports)
       end
     end
 
+    def collect_coverage_reports!(coverage_report)
+      each_report(Ci::JobArtifact::COVERAGE_REPORT_FILE_TYPES) do |file_type, blob|
+        Gitlab::Ci::Parsers.fabricate!(file_type).parse!(blob, coverage_report)
+      end
+
+      coverage_report
+    end
+
     def report_artifacts
       job_artifacts.with_reports
     end
diff --git a/app/models/ci/job_artifact.rb b/app/models/ci/job_artifact.rb
index 38730357593e7..ae57da9c5461e 100644
--- a/app/models/ci/job_artifact.rb
+++ b/app/models/ci/job_artifact.rb
@@ -11,6 +11,7 @@ class JobArtifact < ApplicationRecord
     NotSupportedAdapterError = Class.new(StandardError)
 
     TEST_REPORT_FILE_TYPES = %w[junit].freeze
+    COVERAGE_REPORT_FILE_TYPES = %w[cobertura].freeze
     NON_ERASABLE_FILE_TYPES = %w[trace].freeze
     DEFAULT_FILE_NAMES = {
       archive: nil,
@@ -29,7 +30,8 @@ class JobArtifact < ApplicationRecord
       performance: 'performance.json',
       metrics: 'metrics.txt',
       lsif: 'lsif.json',
-      dotenv: '.env'
+      dotenv: '.env',
+      cobertura: 'cobertura-coverage.xml'
     }.freeze
 
     INTERNAL_TYPES = {
@@ -45,6 +47,7 @@ class JobArtifact < ApplicationRecord
       network_referee: :gzip,
       lsif: :gzip,
       dotenv: :gzip,
+      cobertura: :gzip,
 
       # All these file formats use `raw` as we need to store them uncompressed
       # for Frontend to fetch the files and do analysis
@@ -92,6 +95,10 @@ class JobArtifact < ApplicationRecord
       with_file_types(TEST_REPORT_FILE_TYPES)
     end
 
+    scope :coverage_reports, -> do
+      with_file_types(COVERAGE_REPORT_FILE_TYPES)
+    end
+
     scope :erasable, -> do
       types = self.file_types.reject { |file_type| NON_ERASABLE_FILE_TYPES.include?(file_type) }.values
 
@@ -121,7 +128,8 @@ class JobArtifact < ApplicationRecord
       metrics_referee: 13, ## runner referees
       network_referee: 14, ## runner referees
       lsif: 15, # LSIF data for code navigation
-      dotenv: 16
+      dotenv: 16,
+      cobertura: 17
     }
 
     enum file_format: {
diff --git a/app/models/ci/pipeline.rb b/app/models/ci/pipeline.rb
index b7bab9bc2263a..61b28a3e712a6 100644
--- a/app/models/ci/pipeline.rb
+++ b/app/models/ci/pipeline.rb
@@ -820,6 +820,14 @@ def test_reports_count
       end
     end
 
+    def coverage_reports
+      Gitlab::Ci::Reports::CoverageReports.new.tap do |coverage_reports|
+        builds.latest.with_reports(Ci::JobArtifact.coverage_reports).each do |build|
+          build.collect_coverage_reports!(coverage_reports)
+        end
+      end
+    end
+
     def has_exposed_artifacts?
       complete? && builds.latest.with_exposed_artifacts.exists?
     end
diff --git a/app/models/event.rb b/app/models/event.rb
index 606c4d8302f20..18682bd694c32 100644
--- a/app/models/event.rb
+++ b/app/models/event.rb
@@ -135,29 +135,11 @@ def present
     super(presenter_class: ::EventPresenter)
   end
 
-  # rubocop:disable Metrics/CyclomaticComplexity
-  # rubocop:disable Metrics/PerceivedComplexity
   def visible_to_user?(user = nil)
-    if push_action? || commit_note?
-      Ability.allowed?(user, :download_code, project)
-    elsif membership_changed?
-      Ability.allowed?(user, :read_project, project)
-    elsif created_project_action?
-      Ability.allowed?(user, :read_project, project)
-    elsif issue? || issue_note?
-      Ability.allowed?(user, :read_issue, note? ? note_target : target)
-    elsif merge_request? || merge_request_note?
-      Ability.allowed?(user, :read_merge_request, note? ? note_target : target)
-    elsif personal_snippet_note? || project_snippet_note?
-      Ability.allowed?(user, :read_snippet, note_target)
-    elsif milestone?
-      Ability.allowed?(user, :read_milestone, project)
-    else
-      false # No other event types are visible
-    end
+    return false unless capability.present?
+
+    Ability.allowed?(user, capability, permission_object)
   end
-  # rubocop:enable Metrics/PerceivedComplexity
-  # rubocop:enable Metrics/CyclomaticComplexity
 
   def resource_parent
     project || group
@@ -364,8 +346,38 @@ def to_partial_path
     Event._to_partial_path
   end
 
+  protected
+
+  def capability
+    @capability ||= begin
+                      if push_action? || commit_note?
+                        :download_code
+                      elsif membership_changed? || created_project_action?
+                        :read_project
+                      elsif issue? || issue_note?
+                        :read_issue
+                      elsif merge_request? || merge_request_note?
+                        :read_merge_request
+                      elsif personal_snippet_note? || project_snippet_note?
+                        :read_snippet
+                      elsif milestone?
+                        :read_milestone
+                      end
+                    end
+  end
+
   private
 
+  def permission_object
+    if note?
+      note_target
+    elsif target_id.present?
+      target
+    else
+      project
+    end
+  end
+
   def push_action_name
     if new_ref?
       "pushed new"
diff --git a/app/models/merge_request.rb b/app/models/merge_request.rb
index d165c88fd48f7..412d0fa4ec84a 100644
--- a/app/models/merge_request.rb
+++ b/app/models/merge_request.rb
@@ -567,6 +567,10 @@ def modified_paths(past_merge_request_diff: nil)
     diffs.modified_paths
   end
 
+  def new_paths
+    diffs.diff_files.map(&:new_path)
+  end
+
   def diff_base_commit
     if merge_request_diff.persisted?
       merge_request_diff.base_commit
@@ -1295,6 +1299,24 @@ def compare_test_reports
     compare_reports(Ci::CompareTestReportsService)
   end
 
+  def has_coverage_reports?
+    return false unless Feature.enabled?(:coverage_report_view, project)
+
+    actual_head_pipeline&.has_reports?(Ci::JobArtifact.coverage_reports)
+  end
+
+  # TODO: this method and compare_test_reports use the same
+  # result type, which is handled by the controller's #reports_response.
+  # we should minimize mistakes by isolating the common parts.
+  # issue: https://gitlab.com/gitlab-org/gitlab/issues/34224
+  def find_coverage_reports
+    unless has_coverage_reports?
+      return { status: :error, status_reason: 'This merge request does not have coverage reports' }
+    end
+
+    compare_reports(Ci::GenerateCoverageReportsService)
+  end
+
   def has_exposed_artifacts?
     return false unless Feature.enabled?(:ci_expose_arbitrary_artifacts_in_mr, default_enabled: true)
 
@@ -1318,7 +1340,7 @@ def find_exposed_artifacts
   # issue: https://gitlab.com/gitlab-org/gitlab/issues/34224
   def compare_reports(service_class, current_user = nil)
     with_reactive_cache(service_class.name, current_user&.id) do |data|
-      unless service_class.new(project, current_user)
+      unless service_class.new(project, current_user, id: id)
         .latest?(base_pipeline, actual_head_pipeline, data)
         raise InvalidateReactiveCache
       end
@@ -1335,7 +1357,7 @@ def calculate_reactive_cache(identifier, current_user_id = nil, *args)
     raise NameError, service_class unless service_class < Ci::CompareReportsBaseService
 
     current_user = User.find_by(id: current_user_id)
-    service_class.new(project, current_user).execute(base_pipeline, actual_head_pipeline)
+    service_class.new(project, current_user, id: id).execute(base_pipeline, actual_head_pipeline)
   end
 
   def all_commits
diff --git a/app/models/user.rb b/app/models/user.rb
index 17850d13e489a..0c7dfac57769c 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -1672,6 +1672,16 @@ def dismissed_callout?(feature_name:, ignore_dismissal_earlier_than: nil)
     callouts.any?
   end
 
+  def gitlab_employee?
+    strong_memoize(:gitlab_employee) do
+      if Gitlab.com?
+        Mail::Address.new(email).domain == "gitlab.com"
+      else
+        false
+      end
+    end
+  end
+
   # @deprecated
   alias_method :owned_or_masters_groups, :owned_or_maintainers_groups
 
diff --git a/app/presenters/projects/import_export/project_export_presenter.rb b/app/presenters/projects/import_export/project_export_presenter.rb
new file mode 100644
index 0000000000000..8f3fc53af1037
--- /dev/null
+++ b/app/presenters/projects/import_export/project_export_presenter.rb
@@ -0,0 +1,40 @@
+# frozen_string_literal: true
+
+module Projects
+  module ImportExport
+    class ProjectExportPresenter < Gitlab::View::Presenter::Delegated
+      include ActiveModel::Serializers::JSON
+
+      presents :project
+
+      def project_members
+        super + converted_group_members
+      end
+
+      def description
+        self.respond_to?(:override_description) ? override_description : super
+      end
+
+      private
+
+      def converted_group_members
+        group_members.each do |group_member|
+          group_member.source_type = 'Project' # Make group members project members of the future import
+        end
+      end
+
+      # rubocop: disable CodeReuse/ActiveRecord
+      def group_members
+        return [] unless current_user.can?(:admin_group, project.group)
+
+        # We need `.where.not(user_id: nil)` here otherwise when a group has an
+        # invitee, it would make the following query return 0 rows since a NULL
+        # user_id would be present in the subquery
+        # See http://stackoverflow.com/questions/129077/not-in-clause-and-null-values
+        non_null_user_ids = project.project_members.where.not(user_id: nil).select(:user_id)
+        GroupMembersFinder.new(project.group).execute.where.not(user_id: non_null_user_ids)
+      end
+      # rubocop: enable CodeReuse/ActiveRecord
+    end
+  end
+end
diff --git a/app/services/ci/generate_coverage_reports_service.rb b/app/services/ci/generate_coverage_reports_service.rb
new file mode 100644
index 0000000000000..ebd1eaf0bade1
--- /dev/null
+++ b/app/services/ci/generate_coverage_reports_service.rb
@@ -0,0 +1,30 @@
+# frozen_string_literal: true
+
+module Ci
+  # TODO: a couple of points with this approach:
+  # + reuses existing architecture and reactive caching
+  # - it's not a report comparison and some comparing features must be turned off.
+  # see CompareReportsBaseService for more notes.
+  # issue: https://gitlab.com/gitlab-org/gitlab/issues/34224
+  class GenerateCoverageReportsService < CompareReportsBaseService
+    def execute(base_pipeline, head_pipeline)
+      merge_request = MergeRequest.find_by_id(params[:id])
+      {
+        status: :parsed,
+        key: key(base_pipeline, head_pipeline),
+        data: head_pipeline.coverage_reports.pick(merge_request.new_paths)
+      }
+    rescue => e
+      Gitlab::ErrorTracking.track_exception(e, project_id: project.id)
+      {
+        status: :error,
+        key: key(base_pipeline, head_pipeline),
+        status_reason: _('An error occurred while fetching coverage reports.')
+      }
+    end
+
+    def latest?(base_pipeline, head_pipeline, data)
+      data&.fetch(:key, nil) == key(base_pipeline, head_pipeline)
+    end
+  end
+end
diff --git a/app/services/projects/import_export/export_service.rb b/app/services/projects/import_export/export_service.rb
index 74d5af41a0407..f4214410226a2 100644
--- a/app/services/projects/import_export/export_service.rb
+++ b/app/services/projects/import_export/export_service.rb
@@ -54,7 +54,16 @@ def avatar_saver
       end
 
       def project_tree_saver
-        Gitlab::ImportExport::Project::TreeSaver.new(project: project, current_user: current_user, shared: shared, params: params)
+        tree_saver_class.new(project: project, current_user: current_user, shared: shared, params: params)
+      end
+
+      def tree_saver_class
+        if ::Feature.enabled?(:streaming_serializer, project)
+          Gitlab::ImportExport::Project::TreeSaver
+        else
+          # Once we remove :streaming_serializer feature flag, Project::LegacyTreeSaver should be removed as well
+          Gitlab::ImportExport::Project::LegacyTreeSaver
+        end
       end
 
       def uploads_saver
diff --git a/app/views/projects/merge_requests/show.html.haml b/app/views/projects/merge_requests/show.html.haml
index d65c874f2453a..4304a18558e4b 100644
--- a/app/views/projects/merge_requests/show.html.haml
+++ b/app/views/projects/merge_requests/show.html.haml
@@ -78,6 +78,7 @@
         endpoint: diffs_project_merge_request_path(@project, @merge_request, 'json', request.query_parameters),
         endpoint_metadata: diffs_metadata_project_json_merge_request_path(@project, @merge_request, 'json', request.query_parameters),
         endpoint_batch: diffs_batch_project_json_merge_request_path(@project, @merge_request, 'json', request.query_parameters),
+        endpoint_coverage: @coverage_path,
         help_page_path: suggest_changes_help_path,
         current_user_data: @current_user_data,
         project_path: project_path(@merge_request.project),
diff --git a/bin/background_jobs b/bin/background_jobs
index 06f26df54093b..b3d7cc04d4fac 100755
--- a/bin/background_jobs
+++ b/bin/background_jobs
@@ -1,91 +1,9 @@
 #!/bin/sh
 
 cd $(dirname $0)/..
-app_root=$(pwd)
-sidekiq_pidfile="$app_root/tmp/pids/sidekiq.pid"
-sidekiq_logfile="$app_root/log/sidekiq.log"
-sidekiq_config="$app_root/config/sidekiq_queues.yml"
-gitlab_user=$(ls -l config.ru | awk '{print $3}')
 
-warn()
-{
-  echo "$@" 1>&2
-}
-
-stop()
-{
-  bundle exec sidekiqctl stop $sidekiq_pidfile >> $sidekiq_logfile 2>&1
-}
-
-killall()
-{
-  pkill -u $gitlab_user -f 'sidekiq [0-9]'
-}
-
-restart()
-{
-  if [ -f $sidekiq_pidfile ]; then
-    stop
-  fi
-  killall
-  start_sidekiq -P $sidekiq_pidfile -d -L $sidekiq_logfile >> $sidekiq_logfile 2>&1
-}
-
-start_no_deamonize()
-{
-  start_sidekiq >> $sidekiq_logfile 2>&1
-}
-
-start_sidekiq()
-{
-  cmd="exec"
-  chpst=$(which chpst)
-
-  if [ -n "$chpst" ]; then
-    cmd="${cmd} ${chpst} -P"
-  fi
-
-  ${cmd} bundle exec sidekiq -C "${sidekiq_config}" -e $RAILS_ENV "$@"
-}
-
-load_ok()
-{
-  sidekiq_pid=$(cat $sidekiq_pidfile)
-  if [ -z "$sidekiq_pid" ] ; then
-    warn "Could not find a PID in $sidekiq_pidfile"
-    exit 0
-  fi
-
-  if (ps -p $sidekiq_pid -o args | grep '\([0-9]\+\) of \1 busy' 1>&2) ; then
-    warn "Too many busy Sidekiq workers"
-    exit 1
-  fi
-
-  exit 0
-}
-
-case "$1" in
-  stop)
-    stop
-    ;;
-  start)
-    restart
-    ;;
-  start_no_deamonize)
-    start_no_deamonize
-    ;;
-  start_foreground)
-    start_sidekiq
-    ;;
-  restart)
-    restart
-    ;;
-  killall)
-    killall
-    ;;
-  load_ok)
-    load_ok
-    ;;
-  *)
-    echo "Usage: RAILS_ENV=your_env $0 {stop|start|start_no_deamonize|restart|killall|load_ok}"
-esac
+if [ -n "$SIDEKIQ_WORKERS" ] ; then
+  exec bin/background_jobs_sk_cluster "$@"
+else
+  exec bin/background_jobs_sk "$@"
+fi
diff --git a/bin/background_jobs_sk b/bin/background_jobs_sk
new file mode 100755
index 0000000000000..25218718bb823
--- /dev/null
+++ b/bin/background_jobs_sk
@@ -0,0 +1,67 @@
+#!/bin/sh
+
+cd $(dirname $0)/..
+app_root=$(pwd)
+sidekiq_pidfile="$app_root/tmp/pids/sidekiq.pid"
+sidekiq_logfile="$app_root/log/sidekiq.log"
+sidekiq_config="$app_root/config/sidekiq_queues.yml"
+gitlab_user=$(ls -l config.ru | awk '{print $3}')
+
+warn()
+{
+  echo "$@" 1>&2
+}
+
+stop()
+{
+  bundle exec sidekiqctl stop $sidekiq_pidfile >> $sidekiq_logfile 2>&1
+}
+
+restart()
+{
+  if [ -f $sidekiq_pidfile ]; then
+    stop
+  fi
+
+  pkill -u $gitlab_user -f 'sidekiq [0-9]'
+  start_sidekiq -P $sidekiq_pidfile -d -L $sidekiq_logfile >> $sidekiq_logfile 2>&1
+}
+
+# Starts on foreground but output to the logfile instead stdout.
+start_silent()
+{
+  start_sidekiq >> $sidekiq_logfile 2>&1
+}
+
+start_sidekiq()
+{
+  cmd="exec"
+  chpst=$(which chpst)
+
+  if [ -n "$chpst" ]; then
+    cmd="${cmd} ${chpst} -P"
+  fi
+
+  ${cmd} bundle exec sidekiq -C "${sidekiq_config}" -e $RAILS_ENV "$@"
+}
+
+case "$1" in
+  stop)
+    stop
+    ;;
+  start)
+    restart
+    ;;
+  start_silent)
+    warn "Deprecated: Will be removed at 13.0 (see https://gitlab.com/gitlab-org/gitlab/-/issues/196731)."
+    start_silent
+    ;;
+  start_foreground)
+    start_sidekiq
+    ;;
+  restart)
+    restart
+    ;;
+  *)
+    echo "Usage: RAILS_ENV=<env> $0 {stop|start|start_silent|start_foreground|restart}"
+esac
diff --git a/bin/background_jobs_sk_cluster b/bin/background_jobs_sk_cluster
new file mode 100755
index 0000000000000..9f44bb7381f3d
--- /dev/null
+++ b/bin/background_jobs_sk_cluster
@@ -0,0 +1,76 @@
+#!/bin/sh
+
+cd $(dirname $0)/..
+app_root=$(pwd)
+sidekiq_pidfile="$app_root/tmp/pids/sidekiq-cluster.pid"
+sidekiq_logfile="$app_root/log/sidekiq.log"
+gitlab_user=$(ls -l config.ru | awk '{print $3}')
+
+warn()
+{
+  echo "$@" 1>&2
+}
+
+get_sidekiq_pid() 
+{
+  if [ ! -f $sidekiq_pidfile ]; then
+    warn "No pidfile found at $sidekiq_pidfile; is Sidekiq running?"
+    return
+  fi
+
+  cat $sidekiq_pidfile
+}
+
+stop()
+{
+  sidekiq_pid=$(get_sidekiq_pid)
+
+  if [ $sidekiq_pid ]; then
+    kill -TERM $sidekiq_pid
+  fi
+}
+
+restart()
+{
+  if [ -f $sidekiq_pidfile ]; then
+    stop
+  fi
+
+  warn "Sidekiq output will be written to $sidekiq_logfile"
+  start_sidekiq >> $sidekiq_logfile 2>&1
+}
+
+start_sidekiq()
+{
+  cmd="exec"
+  chpst=$(which chpst)
+
+  if [ -n "$chpst" ]; then
+    cmd="${cmd} ${chpst} -P"
+  fi
+
+  # sidekiq-cluster expects '*' '*' arguments (one wildcard for each process).
+  for (( i=1; i<=$SIDEKIQ_WORKERS; i++ ))
+  do
+    processes_args+=("*")
+  done
+
+  ${cmd} bin/sidekiq-cluster "${processes_args[@]}" -P $sidekiq_pidfile -e $RAILS_ENV
+}
+
+case "$1" in
+  stop)
+    stop
+    ;;
+  start)
+    restart &
+    ;;
+  start_foreground)
+    start_sidekiq
+    ;;
+  restart)
+    restart &
+    ;;
+  *)
+    echo "Usage: RAILS_ENV=<env> SIDEKIQ_WORKERS=<n> $0 {stop|start|start_foreground|restart}"
+esac
diff --git a/changelogs/unreleased/enable-customizable-cycle-analytics.yml b/changelogs/unreleased/enable-customizable-cycle-analytics.yml
new file mode 100644
index 0000000000000..3f981cb4fd3a4
--- /dev/null
+++ b/changelogs/unreleased/enable-customizable-cycle-analytics.yml
@@ -0,0 +1,5 @@
+---
+title: Enable customizable_cycle_analytics feature flag by default
+merge_request: 27418
+author:
+type: changed
diff --git a/changelogs/unreleased/feat-mr-diff-coverage-visualisation.yml b/changelogs/unreleased/feat-mr-diff-coverage-visualisation.yml
new file mode 100644
index 0000000000000..f0ff247edbed9
--- /dev/null
+++ b/changelogs/unreleased/feat-mr-diff-coverage-visualisation.yml
@@ -0,0 +1,5 @@
+---
+title: Add Cobertura XML coverage visualization to merge request diff view
+merge_request: 21791
+author: Fabio Huser
+type: added
diff --git a/changelogs/unreleased/osw-support-opt-in-cluster-in-bg-jobs-script.yml b/changelogs/unreleased/osw-support-opt-in-cluster-in-bg-jobs-script.yml
new file mode 100644
index 0000000000000..847b0f4391972
--- /dev/null
+++ b/changelogs/unreleased/osw-support-opt-in-cluster-in-bg-jobs-script.yml
@@ -0,0 +1,5 @@
+---
+title: Support sidekiq-cluster supervision through bin/background_jobs
+merge_request: 27042
+author:
+type: added
diff --git a/changelogs/unreleased/validate-subnets-field.yml b/changelogs/unreleased/validate-subnets-field.yml
new file mode 100644
index 0000000000000..9d444f8825592
--- /dev/null
+++ b/changelogs/unreleased/validate-subnets-field.yml
@@ -0,0 +1,5 @@
+---
+title: Validate that users selects at least two subnets in EKS Form
+merge_request: 26936
+author:
+type: fixed
diff --git a/config/routes/merge_requests.rb b/config/routes/merge_requests.rb
index f9670a5bf6e81..fe58649b684f3 100644
--- a/config/routes/merge_requests.rb
+++ b/config/routes/merge_requests.rb
@@ -14,6 +14,7 @@
     post :rebase
     get :test_reports
     get :exposed_artifacts
+    get :coverage_reports
 
     scope constraints: ->(req) { req.format == :json }, as: :json do
       get :commits
diff --git a/danger/telemetry/Dangerfile b/danger/telemetry/Dangerfile
index a9e66da6ab703..68a226ef11be1 100644
--- a/danger/telemetry/Dangerfile
+++ b/danger/telemetry/Dangerfile
@@ -1,9 +1,9 @@
 # frozen_string_literal: true
 
 TELEMETRY_CHANGED_FILES_MESSAGE = <<~MSG
-This merge request adds or changes files that require a
-review from the Data team and Telemetry team @gitlab-org/growth/telemetry.
-The specific group is mentioned in order to send a notification to team members.
+This merge request adds or changes files for which a
+review from the Data team and Telemetry team is recommended.
+@gitlab-org/growth/telemetry group is mentioned in order to notify team members.
 MSG
 
 usage_data_changed_files = git.modified_files.grep(%r{usage_data})
@@ -12,7 +12,7 @@ if usage_data_changed_files.any?
   warn format(TELEMETRY_CHANGED_FILES_MESSAGE)
 
   USAGE_DATA_FILES_MESSAGE = <<~MSG
-  The following files require a review from the [Data team and Telemetry team](https://gitlab.com/groups/gitlab-org/growth/telemetry/-/group_members?with_inherited_permissions=exclude):
+  For the following files, a review from the [Data team and Telemetry team](https://gitlab.com/groups/gitlab-org/growth/telemetry/-/group_members?with_inherited_permissions=exclude) is recommended:
   MSG
 
   markdown(USAGE_DATA_FILES_MESSAGE + helper.markdown_list(usage_data_changed_files))
diff --git a/db/migrate/20200311141053_add_ci_pipeline_schedules_to_plan_limits.rb b/db/migrate/20200311141053_add_ci_pipeline_schedules_to_plan_limits.rb
new file mode 100644
index 0000000000000..2fc7785fe9c9a
--- /dev/null
+++ b/db/migrate/20200311141053_add_ci_pipeline_schedules_to_plan_limits.rb
@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+class AddCiPipelineSchedulesToPlanLimits < ActiveRecord::Migration[6.0]
+  include Gitlab::Database::MigrationHelpers
+
+  disable_ddl_transaction!
+
+  DOWNTIME = false
+
+  def up
+    add_column_with_default(:plan_limits, :ci_pipeline_schedules, :integer, default: 0, allow_null: false)
+  end
+
+  def down
+    remove_column(:plan_limits, :ci_pipeline_schedules)
+  end
+end
diff --git a/db/migrate/20200311141943_insert_ci_pipeline_schedules_plan_limits.rb b/db/migrate/20200311141943_insert_ci_pipeline_schedules_plan_limits.rb
new file mode 100644
index 0000000000000..d1ad5be5f85cc
--- /dev/null
+++ b/db/migrate/20200311141943_insert_ci_pipeline_schedules_plan_limits.rb
@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+class InsertCiPipelineSchedulesPlanLimits < ActiveRecord::Migration[6.0]
+  DOWNTIME = false
+
+  def change
+    return unless Gitlab.com?
+
+    create_or_update_plan_limit('ci_pipeline_schedules', 'free', 10)
+    create_or_update_plan_limit('ci_pipeline_schedules', 'bronze', 50)
+    create_or_update_plan_limit('ci_pipeline_schedules', 'silver', 50)
+    create_or_update_plan_limit('ci_pipeline_schedules', 'gold', 50)
+  end
+
+  def down
+    return unless Gitlab.com?
+
+    create_or_update_plan_limit('ci_pipeline_schedules', 'free', 0)
+    create_or_update_plan_limit('ci_pipeline_schedules', 'bronze', 0)
+    create_or_update_plan_limit('ci_pipeline_schedules', 'silver', 0)
+    create_or_update_plan_limit('ci_pipeline_schedules', 'gold', 0)
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index c089c4f123afb..5e6dfd0543656 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -3148,6 +3148,7 @@
     t.integer "project_hooks", default: 0, null: false
     t.integer "group_hooks", default: 0, null: false
     t.integer "ci_project_subscriptions", default: 0, null: false
+    t.integer "ci_pipeline_schedules", default: 0, null: false
     t.index ["plan_id"], name: "index_plan_limits_on_plan_id", unique: true
   end
 
diff --git a/doc/administration/instance_limits.md b/doc/administration/instance_limits.md
index 39516cf18812f..56a407490be19 100644
--- a/doc/administration/instance_limits.md
+++ b/doc/administration/instance_limits.md
@@ -109,6 +109,29 @@ Plan.default.limits.update!(ci_project_subscriptions: 500)
 
 NOTE: **Note:** Set the limit to `0` to disable it.
 
+### Number of pipeline schedules
+
+> [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/29566) in GitLab 12.10.
+
+The total number of pipeline schedules can be limited per project. This limit is
+checked each time a new pipeline schedule is created. If a new pipeline schedule
+would cause the total number of pipeline schedules to exceed the limit, the
+pipeline schedule will not be created.
+
+On GitLab.com, different limits are [defined per plan](../user/gitlab_com/index.md#gitlab-cicd),
+and they affect all projects under that plan.
+
+On self-managed instances ([GitLab Starter](https://about.gitlab.com/pricing/#self-managed)
+or higher tiers), this limit is defined for the `default` plan that affects all
+projects. By default, there is no limit.
+
+To set this limit on a self-managed installation, run the following in the
+[GitLab Rails console](https://docs.gitlab.com/omnibus/maintenance/#starting-a-rails-console-session):
+
+```ruby
+Plan.default.limits.update!(ci_pipeline_schedules: 100)
+```
+
 ## Environment data on Deploy Boards
 
 [Deploy Boards](../user/project/deploy_boards.md) load information from Kubernetes about
diff --git a/doc/api/api_resources.md b/doc/api/api_resources.md
index 7685a56407605..0ce4efa7d9f6a 100644
--- a/doc/api/api_resources.md
+++ b/doc/api/api_resources.md
@@ -120,6 +120,7 @@ The following API resources are available outside of project and group contexts
 | [Events](events.md)                                | `/events`, `/users/:id/events` (also available for projects)            |
 | [Feature flags](features.md)                       | `/features`                                                             |
 | [Geo Nodes](geo_nodes.md) **(PREMIUM ONLY)**       | `/geo_nodes`                                                            |
+| [Group Activity Analytics](group_activity_analytics.md) **(STARTER)**  | `/analytics/group_activity/{issues_count | merge_requests_count}`  |
 | [Import repository from GitHub](import.md)         | `/import/github`                                                        |
 | [Issues](issues.md)                                | `/issues` (also available for groups and projects)                      |
 | [Issues Statistics](issues_statistics.md)          | `/issues_statistics` (also available for groups and projects)           |
diff --git a/doc/api/graphql/reference/gitlab_schema.graphql b/doc/api/graphql/reference/gitlab_schema.graphql
index 86942c489b3fa..74ec8efbe9948 100644
--- a/doc/api/graphql/reference/gitlab_schema.graphql
+++ b/doc/api/graphql/reference/gitlab_schema.graphql
@@ -1988,8 +1988,7 @@ type Epic implements Noteable {
   descendantCounts: EpicDescendantCount
 
   """
-  Total weight of open and closed issues in the epic and its descendants.
-  Available only when feature flag `unfiltered_epic_aggregates` is enabled.
+  Total weight of open and closed issues in the epic and its descendants
   """
   descendantWeightSum: EpicDescendantWeights
 
diff --git a/doc/api/graphql/reference/gitlab_schema.json b/doc/api/graphql/reference/gitlab_schema.json
index d618ca38772c3..8eb9b53af04e2 100644
--- a/doc/api/graphql/reference/gitlab_schema.json
+++ b/doc/api/graphql/reference/gitlab_schema.json
@@ -5847,7 +5847,7 @@
             },
             {
               "name": "descendantWeightSum",
-              "description": "Total weight of open and closed issues in the epic and its descendants. Available only when feature flag `unfiltered_epic_aggregates` is enabled.",
+              "description": "Total weight of open and closed issues in the epic and its descendants",
               "args": [
 
               ],
diff --git a/doc/api/graphql/reference/index.md b/doc/api/graphql/reference/index.md
index 5d60371467438..d6a427d045c58 100644
--- a/doc/api/graphql/reference/index.md
+++ b/doc/api/graphql/reference/index.md
@@ -327,7 +327,7 @@ Represents an epic.
 | `closedAt` | Time | Timestamp of the epic's closure |
 | `createdAt` | Time | Timestamp of the epic's creation |
 | `descendantCounts` | EpicDescendantCount | Number of open and closed descendant epics and issues |
-| `descendantWeightSum` | EpicDescendantWeights | Total weight of open and closed issues in the epic and its descendants. Available only when feature flag `unfiltered_epic_aggregates` is enabled. |
+| `descendantWeightSum` | EpicDescendantWeights | Total weight of open and closed issues in the epic and its descendants |
 | `description` | String | Description of the epic |
 | `downvotes` | Int! | Number of downvotes the epic has received |
 | `dueDate` | Time | Due date of the epic |
diff --git a/doc/api/group_activity_analytics.md b/doc/api/group_activity_analytics.md
new file mode 100644
index 0000000000000..2e93967fe6400
--- /dev/null
+++ b/doc/api/group_activity_analytics.md
@@ -0,0 +1,55 @@
+# Group Activity Analytics API
+
+> **Note:** This feature was [introduced](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/26460) in GitLab 12.9.
+
+## Get count of recently created issues for group
+
+```plaintext
+GET /analytics/group_activity/issues_count
+```
+
+Parameters:
+
+| Attribute | Type | Required | Description |
+| --------- | ---- | -------- | ----------- |
+| `group_path` | string | yes | Group path |
+
+Example request:
+
+```shell
+curl --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab.example.com/api/v4/analytics/group_activity/issues_count?group_path=gitlab-org
+```
+
+Example response:
+
+```json
+[
+  { issues_count : 10 }
+]
+```
+
+## Get count of recently created merge requests for group
+
+```plaintext
+GET /analytics/group_activity/merge_requests_count
+```
+
+Parameters:
+
+| Attribute | Type | Required | Description |
+| --------- | ---- | -------- | ----------- |
+| `group_path` | string | yes | Group path |
+
+Example request:
+
+```shell
+curl --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab.example.com/api/v4/analytics/group_activity/merge_requests_count?group_path=gitlab-org
+```
+
+Example response:
+
+```json
+[
+  { merge_requests_count : 10 }
+]
+```
diff --git a/doc/ci/yaml/README.md b/doc/ci/yaml/README.md
index 50667a402f26d..404f2e073842f 100644
--- a/doc/ci/yaml/README.md
+++ b/doc/ci/yaml/README.md
@@ -107,7 +107,7 @@ The following table lists available parameters for jobs:
 | [`when`](#when)                                    | When to run job. Also available: `when:manual` and `when:delayed`.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
 | [`environment`](#environment)                      | Name of an environment to which the job deploys. Also available: `environment:name`, `environment:url`, `environment:on_stop`, `environment:auto_stop_in` and `environment:action`.                                                                                                                                                                                                                                                                                                                                                                                                                                |
 | [`cache`](#cache)                                  | List of files that should be cached between subsequent runs. Also available: `cache:paths`, `cache:key`, `cache:untracked`, and `cache:policy`.                                                                                                                                                                                                                                                                                                                                                                                                                                         |
-| [`artifacts`](#artifacts)                          | List of files and directories to attach to a job on success. Also available: `artifacts:paths`, `artifacts:expose_as`, `artifacts:name`, `artifacts:untracked`, `artifacts:when`, `artifacts:expire_in`, `artifacts:reports`, and `artifacts:reports:junit`.<br><br>In GitLab [Enterprise Edition](https://about.gitlab.com/pricing/), these are available: `artifacts:reports:codequality`, `artifacts:reports:sast`, `artifacts:reports:dependency_scanning`, `artifacts:reports:container_scanning`, `artifacts:reports:dast`, `artifacts:reports:license_management`, `artifacts:reports:performance` and `artifacts:reports:metrics`. |
+| [`artifacts`](#artifacts)                          | List of files and directories to attach to a job on success. Also available: `artifacts:paths`, `artifacts:expose_as`, `artifacts:name`, `artifacts:untracked`, `artifacts:when`, `artifacts:expire_in`, `artifacts:reports`, `artifacts:reports:junit`, and `artifacts:reports:cobertura`.<br><br>In GitLab [Enterprise Edition](https://about.gitlab.com/pricing/), these are available: `artifacts:reports:codequality`, `artifacts:reports:sast`, `artifacts:reports:dependency_scanning`, `artifacts:reports:container_scanning`, `artifacts:reports:dast`, `artifacts:reports:license_management`, `artifacts:reports:performance` and `artifacts:reports:metrics`. |
 | [`dependencies`](#dependencies)                    | Restrict which artifacts are passed to a specific job by providing a list of jobs to fetch artifacts from.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
 | [`coverage`](#coverage)                            | Code coverage settings for a given job.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
 | [`retry`](#retry)                                  | When and how many times a job can be auto-retried in case of a failure.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
@@ -2286,6 +2286,18 @@ There are a couple of limitations on top of the [original dotenv rules](https://
 - It doesn't support empty lines and comments (`#`) in dotenv file.
 - It doesn't support quote escape, spaces in a quote, a new line expansion in a quote, in dotenv file.
 
+##### `artifacts:reports:cobertura`
+
+> [Introduced](https://gitlab.com/gitlab-org/gitlab/issues/3708) in GitLab 12.9.
+> Requires [GitLab Runner](https://docs.gitlab.com/runner/) 11.5 and above.
+
+The `cobertura` report collects [Cobertura coverage XML files](../../user/project/merge_requests/test_coverage_visualization.md).
+The collected Cobertura coverage reports will be uploaded to GitLab as an artifact
+and will be automatically shown in merge requests.
+
+Cobertura was originally developed for Java, but there are many
+third party ports for other languages like JavaScript, Python, Ruby, etc.
+
 ##### `artifacts:reports:codequality` **(STARTER)**
 
 > Introduced in GitLab 11.5. Requires GitLab Runner 11.5 and above.
diff --git a/doc/user/gitlab_com/index.md b/doc/user/gitlab_com/index.md
index b81426d9089d0..7d0614d411a63 100644
--- a/doc/user/gitlab_com/index.md
+++ b/doc/user/gitlab_com/index.md
@@ -76,6 +76,7 @@ Below are the current settings regarding [GitLab CI/CD](../../ci/README.md).
 | Artifacts [expiry time](../../ci/yaml/README.md#artifactsexpire_in)   | kept forever           | deleted after 30 days unless otherwise specified    |
 | Scheduled Pipeline Cron | `*/5 * * * *` | `19 * * * *` |
 | [Max jobs in active pipelines](../../administration/instance_limits.md#number-of-jobs-in-active-pipelines) | `500` for Free tier, unlimited otherwise | Unlimited
+| [Max pipeline schedules in projects](../../administration/instance_limits.md#number-of-pipeline-schedules) | `10` for Free tier, `50` for all paid tiers | Unlimited |
 
 ## Repository size limit
 
diff --git a/doc/user/project/merge_requests/img/test_coverage_visualization_v12_9.png b/doc/user/project/merge_requests/img/test_coverage_visualization_v12_9.png
new file mode 100644
index 0000000000000..c2cd28adc95b6
Binary files /dev/null and b/doc/user/project/merge_requests/img/test_coverage_visualization_v12_9.png differ
diff --git a/doc/user/project/merge_requests/index.md b/doc/user/project/merge_requests/index.md
index 8281de33e5f85..f296c3fbd8c02 100644
--- a/doc/user/project/merge_requests/index.md
+++ b/doc/user/project/merge_requests/index.md
@@ -102,6 +102,7 @@ or link to useful information directly in the merge request page:
 | [Multi-Project pipelines](../../../ci/multi_project_pipelines.md) **(PREMIUM)**                        | When you set up GitLab CI/CD across multiple projects, you can visualize the entire pipeline, including all cross-project interdependencies.                                                              |
 | [Pipelines for merge requests](../../../ci/merge_request_pipelines/index.md)                           | Customize a specific pipeline structure for merge requests in order to speed the cycle up by running only important jobs.                                                                                 |
 | [Pipeline Graphs](../../../ci/pipelines/index.md#visualizing-pipelines)                                      | View the status of pipelines within the merge request, including the deployment process.                                                                                                                  |
+| [Test Coverage visualization](test_coverage_visualization.md)                                          | See test coverage results for merge requests, within the file diff.                                                                                                                                       |
 
 ### Security Reports **(ULTIMATE)**
 
diff --git a/doc/user/project/merge_requests/test_coverage_visualization.md b/doc/user/project/merge_requests/test_coverage_visualization.md
new file mode 100644
index 0000000000000..a0a4c5d3743b8
--- /dev/null
+++ b/doc/user/project/merge_requests/test_coverage_visualization.md
@@ -0,0 +1,78 @@
+---
+type: reference, howto
+---
+
+# Test Coverage Visualization
+
+> [Introduced](https://gitlab.com/gitlab-org/gitlab/issues/3708) in GitLab 12.9.
+
+With the help of [GitLab CI/CD](../../../ci/README.md), you can collect the test
+coverage information of your favorite testing or coverage-analysis tool, and visualize
+this information inside the file diff view of your merge requests (MRs). This will allow you
+to see which lines are covered by tests, and which lines still require coverage, before the
+MR is merged.
+
+![Test Coverage Visualization Diff View](img/test_coverage_visualization_v12_9.png)
+
+## How test coverage visualization works
+
+Collecting the coverage information is done via GitLab CI/CD's
+[artifacts reports feature](../../../ci/yaml/README.md#artifactsreports).
+You can specify one or more coverage reports to collect, including wildcard paths.
+GitLab will then take the coverage information in all the files and combine it
+together.
+
+For the coverage analysis to work, you have to provide a properly formated
+[Cobertura XML](https://cobertura.github.io/cobertura/) report to
+[`artifacts:reports:cobertura`](../../../ci/yaml/README.md#artifactsreportscobertura).
+This format was originally developed for Java, but most coverage analysis frameworks
+for other languages have plugins to add support for it, like:
+
+- [simplecov-cobertura](https://rubygems.org/gems/simplecov-cobertura) (Ruby)
+- [gocover-cobertura](https://github.com/t-yuki/gocover-cobertura) (Golang)
+
+Other coverage analysis frameworks support the format out of the box, for example:
+
+- [Istanbul](https://istanbul.js.org/docs/advanced/alternative-reporters/#cobertura) (JavaScript)
+- [Coverage.py](https://coverage.readthedocs.io/en/coverage-5.0/cmd.html#xml-reporting) (Python)
+
+Once configured, if you create a merge request that triggers a pipeline which collects
+coverage reports, the coverage will be shown in the diff view. This includes reports
+from any job in any stage in the pipeline. The coverage will be displayed for each line:
+
+- `covered` (green): lines which have been checked at least once by tests
+- `no test coverage` (orange): lines which are loaded but never executed
+- no coverage information: lines which are non-instrumented or not loaded
+
+Hovering over the coverage bar will provide further information, such as the number
+of times the line was checked by tests.
+
+## Example test coverage configuration
+
+The following [`gitlab-ci.yml`](../../../ci/yaml/README.md) example uses [Mocha](https://mochajs.org/)
+JavaScript testing and [NYC](https://github.com/istanbuljs/nyc) coverage-tooling to
+generate the coverage artifact:
+
+```yaml
+test:
+  script:
+    - npm install
+    - npx nyc --reporter cobertura mocha
+  artifacts:
+    reports:
+      cobertura: coverage/cobertura-coverage.xml
+```
+
+## Enabling the feature
+
+This feature comes with the `:coverage_report_view` feature flag disabled by
+default. This feature is disabled due to some performance issues with very large
+data sets. When [the performance issue](https://gitlab.com/gitlab-org/gitlab/issues/37725)
+is resolved, the feature will be enabled by default.
+
+To enable this feature, ask a GitLab administrator with Rails console access to
+run the following command:
+
+```ruby
+Feature.enable(:coverage_report_view)
+```
diff --git a/lib/api/entities/discussion.rb b/lib/api/entities/discussion.rb
index dd1dd40da2329..0740de978978f 100644
--- a/lib/api/entities/discussion.rb
+++ b/lib/api/entities/discussion.rb
@@ -5,7 +5,7 @@ module Entities
     class Discussion < Grape::Entity
       expose :id
       expose :individual_note?, as: :individual_note
-      expose :notes, using: Entities::Note
+      expose :notes, using: Entities::NoteWithGitlabEmployeeBadge
     end
   end
 end
diff --git a/lib/api/entities/note_with_gitlab_employee_badge.rb b/lib/api/entities/note_with_gitlab_employee_badge.rb
new file mode 100644
index 0000000000000..2ea300ffeb69e
--- /dev/null
+++ b/lib/api/entities/note_with_gitlab_employee_badge.rb
@@ -0,0 +1,10 @@
+# frozen_string_literal: true
+
+module API
+  module Entities
+    class NoteWithGitlabEmployeeBadge < Note
+      expose :author, using: Entities::UserWithGitlabEmployeeBadge
+      expose :resolved_by, using: Entities::UserWithGitlabEmployeeBadge, if: ->(note, options) { note.resolvable? }
+    end
+  end
+end
diff --git a/lib/api/entities/user_with_gitlab_employee_badge.rb b/lib/api/entities/user_with_gitlab_employee_badge.rb
new file mode 100644
index 0000000000000..36b9f63313220
--- /dev/null
+++ b/lib/api/entities/user_with_gitlab_employee_badge.rb
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+module API
+  module Entities
+    class UserWithGitlabEmployeeBadge < UserBasic
+      expose :gitlab_employee?, as: :is_gitlab_employee, if: ->(user, options) { ::Feature.enabled?(:gitlab_employee_badge) && user.gitlab_employee? }
+    end
+  end
+end
diff --git a/lib/gitlab/ci/config/entry/reports.rb b/lib/gitlab/ci/config/entry/reports.rb
index 994d379900495..40d37f3601af4 100644
--- a/lib/gitlab/ci/config/entry/reports.rb
+++ b/lib/gitlab/ci/config/entry/reports.rb
@@ -14,7 +14,7 @@ class Reports < ::Gitlab::Config::Entry::Node
           ALLOWED_KEYS =
             %i[junit codequality sast dependency_scanning container_scanning
                dast performance license_management license_scanning metrics lsif
-               dotenv].freeze
+               dotenv cobertura].freeze
 
           attributes ALLOWED_KEYS
 
@@ -35,6 +35,7 @@ class Reports < ::Gitlab::Config::Entry::Node
               validates :metrics, array_of_strings_or_string: true
               validates :lsif, array_of_strings_or_string: true
               validates :dotenv, array_of_strings_or_string: true
+              validates :cobertura, array_of_strings_or_string: true
             end
           end
 
diff --git a/lib/gitlab/ci/parsers.rb b/lib/gitlab/ci/parsers.rb
index c76cd5ff28512..a44105d53c2f5 100644
--- a/lib/gitlab/ci/parsers.rb
+++ b/lib/gitlab/ci/parsers.rb
@@ -9,7 +9,8 @@ module Parsers
 
       def self.parsers
         {
-          junit: ::Gitlab::Ci::Parsers::Test::Junit
+          junit: ::Gitlab::Ci::Parsers::Test::Junit,
+          cobertura: ::Gitlab::Ci::Parsers::Coverage::Cobertura
         }
       end
 
diff --git a/lib/gitlab/ci/parsers/coverage/cobertura.rb b/lib/gitlab/ci/parsers/coverage/cobertura.rb
new file mode 100644
index 0000000000000..006d5097148b6
--- /dev/null
+++ b/lib/gitlab/ci/parsers/coverage/cobertura.rb
@@ -0,0 +1,64 @@
+# frozen_string_literal: true
+
+module Gitlab
+  module Ci
+    module Parsers
+      module Coverage
+        class Cobertura
+          CoberturaParserError = Class.new(Gitlab::Ci::Parsers::ParserError)
+
+          def parse!(xml_data, coverage_report)
+            root = Hash.from_xml(xml_data)
+
+            parse_all(root, coverage_report)
+          rescue Nokogiri::XML::SyntaxError
+            raise CoberturaParserError, "XML parsing failed"
+          rescue
+            raise CoberturaParserError, "Cobertura parsing failed"
+          end
+
+          private
+
+          def parse_all(root, coverage_report)
+            return unless root.present?
+
+            root.each do |key, value|
+              parse_node(key, value, coverage_report)
+            end
+          end
+
+          def parse_node(key, value, coverage_report)
+            if key == 'class'
+              Array.wrap(value).each do |item|
+                parse_class(item, coverage_report)
+              end
+            elsif value.is_a?(Hash)
+              parse_all(value, coverage_report)
+            elsif value.is_a?(Array)
+              value.each do |item|
+                parse_all(item, coverage_report)
+              end
+            end
+          end
+
+          def parse_class(file, coverage_report)
+            return unless file["filename"].present? && file["lines"].present?
+
+            parsed_lines = parse_lines(file["lines"])
+
+            coverage_report.add_file(file["filename"], Hash[parsed_lines])
+          end
+
+          def parse_lines(lines)
+            line_array = Array.wrap(lines["line"])
+
+            line_array.map do |line|
+              # Using `Integer()` here to raise exception on invalid values
+              [Integer(line["number"]), Integer(line["hits"])]
+            end
+          end
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/ci/reports/coverage_reports.rb b/lib/gitlab/ci/reports/coverage_reports.rb
new file mode 100644
index 0000000000000..31afb636d2f39
--- /dev/null
+++ b/lib/gitlab/ci/reports/coverage_reports.rb
@@ -0,0 +1,43 @@
+# frozen_string_literal: true
+
+module Gitlab
+  module Ci
+    module Reports
+      class CoverageReports
+        attr_reader :files
+
+        def initialize
+          @files = {}
+        end
+
+        def pick(keys)
+          coverage_files = files.select do |key|
+            keys.include?(key)
+          end
+
+          { files: coverage_files }
+        end
+
+        def add_file(name, line_coverage)
+          if files[name].present?
+            line_coverage.each { |line, hits| combine_lines(name, line, hits) }
+
+          else
+            files[name] = line_coverage
+          end
+        end
+
+        private
+
+        def combine_lines(name, line, hits)
+          if files[name][line].present?
+            files[name][line] += hits
+
+          else
+            files[name][line] = hits
+          end
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/import_export/group/tree_saver.rb b/lib/gitlab/import_export/group/tree_saver.rb
index 48f6925884b52..fd1eb329ad28d 100644
--- a/lib/gitlab/import_export/group/tree_saver.rb
+++ b/lib/gitlab/import_export/group/tree_saver.rb
@@ -49,7 +49,7 @@ def reader
         end
 
         def tree_saver
-          @tree_saver ||= RelationTreeSaver.new
+          @tree_saver ||= LegacyRelationTreeSaver.new
         end
       end
     end
diff --git a/lib/gitlab/import_export/json/legacy_writer.rb b/lib/gitlab/import_export/json/legacy_writer.rb
new file mode 100644
index 0000000000000..c935e360a653b
--- /dev/null
+++ b/lib/gitlab/import_export/json/legacy_writer.rb
@@ -0,0 +1,73 @@
+# frozen_string_literal: true
+
+module Gitlab
+  module ImportExport
+    module JSON
+      class LegacyWriter
+        include Gitlab::ImportExport::CommandLineUtil
+
+        attr_reader :path
+
+        def initialize(path)
+          @path = path
+          @last_array = nil
+          @keys = Set.new
+
+          mkdir_p(File.dirname(@path))
+          file.write('{}')
+        end
+
+        def close
+          @file&.close
+          @file = nil
+        end
+
+        def set(hash)
+          hash.each do |key, value|
+            write(key, value)
+          end
+        end
+
+        def write(key, value)
+          raise ArgumentError, "key '#{key}' already written" if @keys.include?(key)
+
+          # rewind by one byte, to overwrite '}'
+          file.pos = file.size - 1
+
+          file.write(',') if @keys.any?
+          file.write(key.to_json)
+          file.write(':')
+          file.write(value.to_json)
+          file.write('}')
+
+          @keys.add(key)
+          @last_array = nil
+          @last_array_count = nil
+        end
+
+        def append(key, value)
+          unless @last_array == key
+            write(key, [])
+
+            @last_array = key
+            @last_array_count = 0
+          end
+
+          # rewind by two bytes, to overwrite ']}'
+          file.pos = file.size - 2
+
+          file.write(',') if @last_array_count > 0
+          file.write(value.to_json)
+          file.write(']}')
+          @last_array_count += 1
+        end
+
+        private
+
+        def file
+          @file ||= File.open(@path, "wb")
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/import_export/json/streaming_serializer.rb b/lib/gitlab/import_export/json/streaming_serializer.rb
new file mode 100644
index 0000000000000..d053bf1616608
--- /dev/null
+++ b/lib/gitlab/import_export/json/streaming_serializer.rb
@@ -0,0 +1,82 @@
+# frozen_string_literal: true
+
+module Gitlab
+  module ImportExport
+    module JSON
+      class StreamingSerializer
+        include Gitlab::ImportExport::CommandLineUtil
+
+        BATCH_SIZE = 100
+
+        class Raw < String
+          def to_json(*_args)
+            to_s
+          end
+        end
+
+        def initialize(exportable, relations_schema, json_writer)
+          @exportable = exportable
+          @relations_schema = relations_schema
+          @json_writer = json_writer
+        end
+
+        def execute
+          serialize_root
+
+          includes.each do |relation_definition|
+            serialize_relation(relation_definition)
+          end
+        end
+
+        private
+
+        attr_reader :json_writer, :relations_schema, :exportable
+
+        def serialize_root
+          attributes = exportable.as_json(
+            relations_schema.merge(include: nil, preloads: nil))
+          json_writer.set(attributes)
+        end
+
+        def serialize_relation(definition)
+          raise ArgumentError, 'definition needs to be Hash' unless definition.is_a?(Hash)
+          raise ArgumentError, 'definition needs to have exactly one Hash element' unless definition.one?
+
+          key, options = definition.first
+
+          record = exportable.public_send(key) # rubocop: disable GitlabSecurity/PublicSend
+          if record.is_a?(ActiveRecord::Relation)
+            serialize_many_relations(key, record, options)
+          else
+            serialize_single_relation(key, record, options)
+          end
+        end
+
+        def serialize_many_relations(key, records, options)
+          key_preloads = preloads&.dig(key)
+          records = records.preload(key_preloads) if key_preloads
+
+          records.find_each(batch_size: BATCH_SIZE) do |record|
+            json = Raw.new(record.to_json(options))
+
+            json_writer.append(key, json)
+          end
+        end
+
+        def serialize_single_relation(key, record, options)
+          json = Raw.new(record.to_json(options))
+
+          json_writer.write(key, json)
+        end
+
+        def includes
+          relations_schema[:include]
+        end
+
+        def preloads
+          relations_schema[:preload]
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/import_export/relation_tree_saver.rb b/lib/gitlab/import_export/legacy_relation_tree_saver.rb
similarity index 94%
rename from lib/gitlab/import_export/relation_tree_saver.rb
rename to lib/gitlab/import_export/legacy_relation_tree_saver.rb
index ed5392c13d07b..fe3e64358e508 100644
--- a/lib/gitlab/import_export/relation_tree_saver.rb
+++ b/lib/gitlab/import_export/legacy_relation_tree_saver.rb
@@ -2,7 +2,7 @@
 
 module Gitlab
   module ImportExport
-    class RelationTreeSaver
+    class LegacyRelationTreeSaver
       include Gitlab::ImportExport::CommandLineUtil
 
       def serialize(exportable, relations_tree)
diff --git a/lib/gitlab/import_export/project/legacy_tree_saver.rb b/lib/gitlab/import_export/project/legacy_tree_saver.rb
new file mode 100644
index 0000000000000..2ed98f52c5873
--- /dev/null
+++ b/lib/gitlab/import_export/project/legacy_tree_saver.rb
@@ -0,0 +1,68 @@
+# frozen_string_literal: true
+
+module Gitlab
+  module ImportExport
+    module Project
+      class LegacyTreeSaver
+        attr_reader :full_path
+
+        def initialize(project:, current_user:, shared:, params: {})
+          @params       = params
+          @project      = project
+          @current_user = current_user
+          @shared       = shared
+          @full_path    = File.join(@shared.export_path, ImportExport.project_filename)
+        end
+
+        def save
+          project_tree = tree_saver.serialize(@project, reader.project_tree)
+          fix_project_tree(project_tree)
+          tree_saver.save(project_tree, @shared.export_path, ImportExport.project_filename)
+
+          true
+        rescue => e
+          @shared.error(e)
+          false
+        end
+
+        private
+
+        # Aware that the resulting hash needs to be pure-hash and
+        # does not include any AR objects anymore, only objects that run `.to_json`
+        def fix_project_tree(project_tree)
+          if @params[:description].present?
+            project_tree['description'] = @params[:description]
+          end
+
+          project_tree['project_members'] += group_members_array
+        end
+
+        def reader
+          @reader ||= Gitlab::ImportExport::Reader.new(shared: @shared)
+        end
+
+        def group_members_array
+          group_members.as_json(reader.group_members_tree).each do |group_member|
+            group_member['source_type'] = 'Project' # Make group members project members of the future import
+          end
+        end
+
+        def group_members
+          return [] unless @current_user.can?(:admin_group, @project.group)
+
+          # We need `.where.not(user_id: nil)` here otherwise when a group has an
+          # invitee, it would make the following query return 0 rows since a NULL
+          # user_id would be present in the subquery
+          # See http://stackoverflow.com/questions/129077/not-in-clause-and-null-values
+          non_null_user_ids = @project.project_members.where.not(user_id: nil).select(:user_id)
+
+          GroupMembersFinder.new(@project.group).execute.where.not(user_id: non_null_user_ids)
+        end
+
+        def tree_saver
+          @tree_saver ||= Gitlab::ImportExport::LegacyRelationTreeSaver.new
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/import_export/project/tree_saver.rb b/lib/gitlab/import_export/project/tree_saver.rb
index 32b3b518ececc..01000c9d6d92e 100644
--- a/lib/gitlab/import_export/project/tree_saver.rb
+++ b/lib/gitlab/import_export/project/tree_saver.rb
@@ -15,52 +15,40 @@ def initialize(project:, current_user:, shared:, params: {})
         end
 
         def save
-          project_tree = tree_saver.serialize(@project, reader.project_tree)
-          fix_project_tree(project_tree)
-          tree_saver.save(project_tree, @shared.export_path, ImportExport.project_filename)
+          json_writer = ImportExport::JSON::LegacyWriter.new(@full_path)
+
+          serializer = ImportExport::JSON::StreamingSerializer.new(exportable, reader.project_tree, json_writer)
+          serializer.execute
 
           true
         rescue => e
           @shared.error(e)
           false
+        ensure
+          json_writer&.close
         end
 
         private
 
-        # Aware that the resulting hash needs to be pure-hash and
-        # does not include any AR objects anymore, only objects that run `.to_json`
-        def fix_project_tree(project_tree)
-          if @params[:description].present?
-            project_tree['description'] = @params[:description]
-          end
-
-          project_tree['project_members'] += group_members_array
-        end
-
         def reader
           @reader ||= Gitlab::ImportExport::Reader.new(shared: @shared)
         end
 
-        def group_members_array
-          group_members.as_json(reader.group_members_tree).each do |group_member|
-            group_member['source_type'] = 'Project' # Make group members project members of the future import
-          end
+        def exportable
+          @project.present(exportable_params)
         end
 
-        def group_members
-          return [] unless @current_user.can?(:admin_group, @project.group)
-
-          # We need `.where.not(user_id: nil)` here otherwise when a group has an
-          # invitee, it would make the following query return 0 rows since a NULL
-          # user_id would be present in the subquery
-          # See http://stackoverflow.com/questions/129077/not-in-clause-and-null-values
-          non_null_user_ids = @project.project_members.where.not(user_id: nil).select(:user_id)
-
-          GroupMembersFinder.new(@project.group).execute.where.not(user_id: non_null_user_ids)
+        def exportable_params
+          params = {
+            presenter_class: presenter_class,
+            current_user: @current_user
+          }
+          params[:override_description] = @params[:description] if @params[:description].present?
+          params
         end
 
-        def tree_saver
-          @tree_saver ||= RelationTreeSaver.new
+        def presenter_class
+          Projects::ImportExport::ProjectExportPresenter
         end
       end
     end
diff --git a/lib/tasks/gitlab/import_export/export.rake b/lib/tasks/gitlab/import_export/export.rake
index ae54636fdd36c..c9c212fbe4d80 100644
--- a/lib/tasks/gitlab/import_export/export.rake
+++ b/lib/tasks/gitlab/import_export/export.rake
@@ -19,7 +19,6 @@ namespace :gitlab do
 
         if ENV['EXPORT_DEBUG'].present?
           ActiveRecord::Base.logger = logger
-          Gitlab::Metrics::Exporter::SidekiqExporter.instance.start
           logger.level = Logger::DEBUG
         else
           logger.level = Logger::INFO
diff --git a/lib/tasks/gitlab/import_export/import.rake b/lib/tasks/gitlab/import_export/import.rake
index 6e2d0e75da880..7e2162a777494 100644
--- a/lib/tasks/gitlab/import_export/import.rake
+++ b/lib/tasks/gitlab/import_export/import.rake
@@ -23,7 +23,6 @@ namespace :gitlab do
 
         if ENV['IMPORT_DEBUG'].present?
           ActiveRecord::Base.logger = logger
-          Gitlab::Metrics::Exporter::SidekiqExporter.instance.start
           logger.level = Logger::DEBUG
         else
           logger.level = Logger::INFO
diff --git a/lib/tasks/sidekiq.rake b/lib/tasks/sidekiq.rake
index e281ebd5d6029..d74878835fd4e 100644
--- a/lib/tasks/sidekiq.rake
+++ b/lib/tasks/sidekiq.rake
@@ -33,6 +33,6 @@ namespace :sidekiq do
   task :launchd do
     deprecation_warning!
 
-    system(*%w(bin/background_jobs start_no_deamonize))
+    system(*%w(bin/background_jobs start_silent))
   end
 end
diff --git a/locale/gitlab.pot b/locale/gitlab.pot
index c7ca9634e0ef4..0a6266635fbbb 100644
--- a/locale/gitlab.pot
+++ b/locale/gitlab.pot
@@ -1810,6 +1810,9 @@ msgstr ""
 msgid "An error occurred while enabling Service Desk."
 msgstr ""
 
+msgid "An error occurred while fetching coverage reports."
+msgstr ""
+
 msgid "An error occurred while fetching environments."
 msgstr ""
 
@@ -4822,6 +4825,9 @@ msgstr ""
 msgid "ClusterIntegration|You must have an RBAC-enabled cluster to install Knative."
 msgstr ""
 
+msgid "ClusterIntegration|You should select at least two subnets"
+msgstr ""
+
 msgid "ClusterIntegration|Your account must have %{link_to_kubernetes_engine}"
 msgstr ""
 
@@ -13325,6 +13331,9 @@ msgstr ""
 msgid "No template"
 msgstr ""
 
+msgid "No test coverage"
+msgstr ""
+
 msgid "No thanks, don't show this again"
 msgstr ""
 
@@ -19472,6 +19481,11 @@ msgstr ""
 msgid "Test coverage parsing"
 msgstr ""
 
+msgid "Test coverage: %d hit"
+msgid_plural "Test coverage: %d hits"
+msgstr[0] ""
+msgstr[1] ""
+
 msgid "Test failed."
 msgstr ""
 
diff --git a/spec/controllers/projects/merge_requests_controller_spec.rb b/spec/controllers/projects/merge_requests_controller_spec.rb
index 3684571ff9ceb..2b1890f6cbd69 100644
--- a/spec/controllers/projects/merge_requests_controller_spec.rb
+++ b/spec/controllers/projects/merge_requests_controller_spec.rb
@@ -984,6 +984,136 @@ def go(format: 'html')
     end
   end
 
+  describe 'GET coverage_reports' do
+    let(:merge_request) do
+      create(:merge_request,
+        :with_merge_request_pipeline,
+        target_project: project,
+        source_project: project)
+    end
+
+    let(:pipeline) do
+      create(:ci_pipeline,
+        :success,
+        project: merge_request.source_project,
+        ref: merge_request.source_branch,
+        sha: merge_request.diff_head_sha)
+    end
+
+    before do
+      allow_any_instance_of(MergeRequest)
+        .to receive(:find_coverage_reports)
+        .and_return(report)
+
+      allow_any_instance_of(MergeRequest)
+        .to receive(:actual_head_pipeline)
+        .and_return(pipeline)
+    end
+
+    subject do
+      get :coverage_reports, params: {
+        namespace_id: project.namespace.to_param,
+        project_id: project,
+        id: merge_request.iid
+      },
+      format: :json
+    end
+
+    describe 'permissions on a public project with private CI/CD' do
+      let(:project) { create :project, :repository, :public, :builds_private }
+      let(:report) { { status: :parsed, data: [] } }
+
+      context 'while signed out' do
+        before do
+          sign_out(user)
+        end
+
+        it 'responds with a 404' do
+          subject
+
+          expect(response).to have_gitlab_http_status(:not_found)
+          expect(response.body).to be_blank
+        end
+      end
+
+      context 'while signed in as an unrelated user' do
+        before do
+          sign_in(create(:user))
+        end
+
+        it 'responds with a 404' do
+          subject
+
+          expect(response).to have_gitlab_http_status(:not_found)
+          expect(response.body).to be_blank
+        end
+      end
+    end
+
+    context 'when pipeline has jobs with coverage reports' do
+      before do
+        allow_any_instance_of(MergeRequest)
+          .to receive(:has_coverage_reports?)
+          .and_return(true)
+      end
+
+      context 'when processing coverage reports is in progress' do
+        let(:report) { { status: :parsing } }
+
+        it 'sends polling interval' do
+          expect(Gitlab::PollingInterval).to receive(:set_header)
+
+          subject
+        end
+
+        it 'returns 204 HTTP status' do
+          subject
+
+          expect(response).to have_gitlab_http_status(:no_content)
+        end
+      end
+
+      context 'when processing coverage reports is completed' do
+        let(:report) { { status: :parsed, data: pipeline.coverage_reports } }
+
+        it 'returns coverage reports' do
+          subject
+
+          expect(response).to have_gitlab_http_status(:ok)
+          expect(json_response).to eq({ 'files' => {} })
+        end
+      end
+
+      context 'when user created corrupted coverage reports' do
+        let(:report) { { status: :error, status_reason: 'Failed to parse coverage reports' } }
+
+        it 'does not send polling interval' do
+          expect(Gitlab::PollingInterval).not_to receive(:set_header)
+
+          subject
+        end
+
+        it 'returns 400 HTTP status' do
+          subject
+
+          expect(response).to have_gitlab_http_status(:bad_request)
+          expect(json_response).to eq({ 'status_reason' => 'Failed to parse coverage reports' })
+        end
+      end
+    end
+
+    context 'when pipeline does not have jobs with coverage reports' do
+      let(:report) { double }
+
+      it 'returns no content' do
+        subject
+
+        expect(response).to have_gitlab_http_status(:no_content)
+        expect(response.body).to be_empty
+      end
+    end
+  end
+
   describe 'GET test_reports' do
     let(:merge_request) do
       create(:merge_request,
diff --git a/spec/factories/ci/builds.rb b/spec/factories/ci/builds.rb
index b6f18240b9eba..446c1c5903092 100644
--- a/spec/factories/ci/builds.rb
+++ b/spec/factories/ci/builds.rb
@@ -311,6 +311,12 @@
       end
     end
 
+    trait :coverage_reports do
+      after(:build) do |build|
+        build.job_artifacts << create(:ci_job_artifact, :cobertura, job: build)
+      end
+    end
+
     trait :expired do
       artifacts_expire_at { 1.minute.ago }
     end
@@ -355,6 +361,8 @@
       options { {} }
     end
 
+    # TODO: move Security traits to ee_ci_build
+    # https://gitlab.com/gitlab-org/gitlab/-/issues/210486
     trait :dast do
       options do
         {
@@ -395,6 +403,14 @@
       end
     end
 
+    trait :license_scanning do
+      options do
+        {
+          artifacts: { reports: { license_management: 'gl-license-scanning-report.json' } }
+        }
+      end
+    end
+
     trait :non_playable do
       status { 'created' }
       self.when { 'manual' }
diff --git a/spec/factories/ci/job_artifacts.rb b/spec/factories/ci/job_artifacts.rb
index e0942bf0ac3e2..8fbf242a607c5 100644
--- a/spec/factories/ci/job_artifacts.rb
+++ b/spec/factories/ci/job_artifacts.rb
@@ -129,6 +129,36 @@
       end
     end
 
+    trait :cobertura do
+      file_type { :cobertura }
+      file_format { :gzip }
+
+      after(:build) do |artifact, evaluator|
+        artifact.file = fixture_file_upload(
+          Rails.root.join('spec/fixtures/cobertura/coverage.xml.gz'), 'application/x-gzip')
+      end
+    end
+
+    trait :coverage_gocov_xml do
+      file_type { :cobertura }
+      file_format { :gzip }
+
+      after(:build) do |artifact, evaluator|
+        artifact.file = fixture_file_upload(
+          Rails.root.join('spec/fixtures/cobertura/coverage_gocov_xml.xml.gz'), 'application/x-gzip')
+      end
+    end
+
+    trait :coverage_with_corrupted_data do
+      file_type { :cobertura }
+      file_format { :gzip }
+
+      after(:build) do |artifact, evaluator|
+        artifact.file = fixture_file_upload(
+          Rails.root.join('spec/fixtures/cobertura/coverage_with_corrupted_data.xml.gz'), 'application/x-gzip')
+      end
+    end
+
     trait :codequality do
       file_type { :codequality }
       file_format { :raw }
diff --git a/spec/factories/ci/pipelines.rb b/spec/factories/ci/pipelines.rb
index 40b2aa3042e51..11686ed5277e5 100644
--- a/spec/factories/ci/pipelines.rb
+++ b/spec/factories/ci/pipelines.rb
@@ -67,6 +67,14 @@
         end
       end
 
+      trait :with_coverage_reports do
+        status { :success }
+
+        after(:build) do |pipeline, evaluator|
+          pipeline.builds << build(:ci_build, :coverage_reports, pipeline: pipeline, project: pipeline.project)
+        end
+      end
+
       trait :with_exposed_artifacts do
         status { :success }
 
diff --git a/spec/factories/merge_requests.rb b/spec/factories/merge_requests.rb
index 2344ffffa65de..f717bab5f2afc 100644
--- a/spec/factories/merge_requests.rb
+++ b/spec/factories/merge_requests.rb
@@ -121,6 +121,18 @@
       end
     end
 
+    trait :with_coverage_reports do
+      after(:build) do |merge_request|
+        merge_request.head_pipeline = build(
+          :ci_pipeline,
+          :success,
+          :with_coverage_reports,
+          project: merge_request.source_project,
+          ref: merge_request.source_branch,
+          sha: merge_request.diff_head_sha)
+      end
+    end
+
     trait :with_exposed_artifacts do
       after(:build) do |merge_request|
         merge_request.head_pipeline = build(
diff --git a/spec/features/merge_request/user_sees_avatar_on_diff_notes_spec.rb b/spec/features/merge_request/user_sees_avatar_on_diff_notes_spec.rb
index c482d783babbd..21599164ac3b3 100644
--- a/spec/features/merge_request/user_sees_avatar_on_diff_notes_spec.rb
+++ b/spec/features/merge_request/user_sees_avatar_on_diff_notes_spec.rb
@@ -190,7 +190,7 @@
 
   def find_line(line_code)
     line = find("[id='#{line_code}']")
-    line = line.find(:xpath, 'preceding-sibling::*[1][self::td]') if line.tag_name == 'td'
+    line = line.find(:xpath, 'preceding-sibling::*[1][self::td]/preceding-sibling::*[1][self::td]') if line.tag_name == 'td'
     line
   end
 end
diff --git a/spec/fixtures/api/schemas/entities/user.json b/spec/fixtures/api/schemas/entities/user.json
index 82d80b75cefef..1e0c888560934 100644
--- a/spec/fixtures/api/schemas/entities/user.json
+++ b/spec/fixtures/api/schemas/entities/user.json
@@ -17,7 +17,8 @@
     "path": { "type": "string" },
     "name": { "type": "string" },
     "username": { "type": "string" },
-    "status_tooltip_html": { "$ref": "../types/nullable_string.json" }
+    "status_tooltip_html": { "$ref": "../types/nullable_string.json" },
+    "is_gitlab_employee": { "type": "boolean" }
   },
   "additionalProperties": false
 }
diff --git a/spec/fixtures/cobertura/coverage.xml b/spec/fixtures/cobertura/coverage.xml
new file mode 100644
index 0000000000000..01e8085b8d82a
--- /dev/null
+++ b/spec/fixtures/cobertura/coverage.xml
@@ -0,0 +1,43 @@
+<?xml version='1.0'?> 
+<!DOCTYPE coverage SYSTEM "http://cobertura.sourceforge.net/xml/coverage-04.dtd">
+<!-- cobertura example file - generated by simplecov-cobertura - subset of gitlab-org/gitlab - manually modified -->
+<!-- Generated by simplecov-cobertura version 1.3.1 (https://github.com/dashingrocket/simplecov-cobertura) -->
+<coverage line-rate="0.5" branch-rate="0" lines-covered="73865" lines-valid="147397" branches-covered="0" branches-valid="0" complexity="0" version="0" timestamp="1577128350">
+  <sources>
+    <source>/tmp/projects/gitlab-ce/gitlab</source>
+  </sources>
+  <packages>
+    <package name="Controllers" line-rate="0.43" branch-rate="0" complexity="0">
+      <classes>
+        <class name="abuse_reports_controller" filename="app/controllers/abuse_reports_controller.rb" line-rate="0.3" branch-rate="0" complexity="0">
+          <methods/>
+          <lines>
+            <line number="3" branch="false" hits="1"/>
+            <line number="4" branch="false" hits="1"/>
+            <line number="6" branch="false" hits="1"/>
+            <line number="7" branch="false" hits="0"/>
+            <line number="8" branch="false" hits="0"/>
+            <line number="9" branch="false" hits="0"/>
+            <line number="12" branch="false" hits="1"/>
+            <line number="13" branch="false" hits="0"/>
+            <line number="14" branch="false" hits="0"/>
+            <line number="16" branch="false" hits="0"/>
+            <line number="17" branch="false" hits="0"/>
+            <line number="19" branch="false" hits="0"/>
+            <line number="20" branch="false" hits="0"/>
+            <line number="22" branch="false" hits="0"/>
+            <line number="26" branch="false" hits="1"/>
+            <line number="28" branch="false" hits="1"/>
+            <line number="29" branch="false" hits="0"/>
+            <line number="36" branch="false" hits="1"/>
+            <line number="37" branch="false" hits="0"/>
+            <line number="39" branch="false" hits="0"/>
+            <line number="40" branch="false" hits="0"/>
+            <line number="41" branch="false" hits="0"/>
+            <line number="42" branch="false" hits="0"/>
+          </lines>
+        </class>
+      </classes>
+    </package>
+  </packages>
+</coverage>
\ No newline at end of file
diff --git a/spec/fixtures/cobertura/coverage.xml.gz b/spec/fixtures/cobertura/coverage.xml.gz
new file mode 100644
index 0000000000000..1a5a5f02ced00
Binary files /dev/null and b/spec/fixtures/cobertura/coverage.xml.gz differ
diff --git a/spec/fixtures/cobertura/coverage_gocov_xml.xml b/spec/fixtures/cobertura/coverage_gocov_xml.xml
new file mode 100644
index 0000000000000..c4da14efb4080
--- /dev/null
+++ b/spec/fixtures/cobertura/coverage_gocov_xml.xml
@@ -0,0 +1,216 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE coverage SYSTEM "http://cobertura.sourceforge.net/xml/coverage-04.dtd">
+<!-- cobertura example file - generated by gocov-xml - subset of gitlab-org/gitaly -->
+<coverage line-rate="0.7966102" branch-rate="0" lines-covered="47" lines-valid="59" branches-covered="0" branches-valid="0" complexity="0" version="" timestamp="1577127162320">
+	<packages>
+		<package name="gitlab.com/gitlab-org/gitaly/auth" line-rate="0.7966102" branch-rate="0" complexity="0" line-count="59" line-hits="47">
+			<classes>
+				<class name="-" filename="auth/rpccredentials.go" line-rate="0.2" branch-rate="0" complexity="0" line-count="5" line-hits="1">
+					<methods>
+						<method name="RPCCredentials" signature="" line-rate="1" branch-rate="0" complexity="0" line-count="0" line-hits="0">
+							<lines>
+								<line number="17" hits="1"></line>
+							</lines>
+						</method>
+						<method name="RPCCredentialsV2" signature="" line-rate="0" branch-rate="0" complexity="0" line-count="0" line-hits="0">
+							<lines>
+								<line number="34" hits="0"></line>
+							</lines>
+						</method>
+						<method name="hmacToken" signature="" line-rate="0" branch-rate="0" complexity="0" line-count="0" line-hits="0">
+							<lines>
+								<line number="52" hits="0"></line>
+								<line number="53" hits="0"></line>
+								<line number="55" hits="0"></line>
+							</lines>
+						</method>
+					</methods>
+					<lines>
+						<line number="17" hits="1"></line>
+						<line number="34" hits="0"></line>
+						<line number="52" hits="0"></line>
+						<line number="53" hits="0"></line>
+						<line number="55" hits="0"></line>
+					</lines>
+				</class>
+				<class name="rpcCredentials" filename="auth/rpccredentials.go" line-rate="0.5" branch-rate="0" complexity="0" line-count="2" line-hits="1">
+					<methods>
+						<method name="RequireTransportSecurity" signature="" line-rate="0" branch-rate="0" complexity="0" line-count="0" line-hits="0">
+							<lines>
+								<line number="24" hits="0"></line>
+							</lines>
+						</method>
+						<method name="GetRequestMetadata" signature="" line-rate="1" branch-rate="0" complexity="0" line-count="0" line-hits="0">
+							<lines>
+								<line number="27" hits="1"></line>
+							</lines>
+						</method>
+					</methods>
+					<lines>
+						<line number="24" hits="0"></line>
+						<line number="27" hits="1"></line>
+					</lines>
+				</class>
+				<class name="rpcCredentialsV2" filename="auth/rpccredentials.go" line-rate="0" branch-rate="0" complexity="0" line-count="3" line-hits="0">
+					<methods>
+						<method name="RequireTransportSecurity" signature="" line-rate="0" branch-rate="0" complexity="0" line-count="0" line-hits="0">
+							<lines>
+								<line number="41" hits="0"></line>
+							</lines>
+						</method>
+						<method name="GetRequestMetadata" signature="" line-rate="0" branch-rate="0" complexity="0" line-count="0" line-hits="0">
+							<lines>
+								<line number="44" hits="0"></line>
+							</lines>
+						</method>
+						<method name="hmacToken" signature="" line-rate="0" branch-rate="0" complexity="0" line-count="0" line-hits="0">
+							<lines>
+								<line number="48" hits="0"></line>
+							</lines>
+						</method>
+					</methods>
+					<lines>
+						<line number="41" hits="0"></line>
+						<line number="44" hits="0"></line>
+						<line number="48" hits="0"></line>
+					</lines>
+				</class>
+				<class name="-" filename="auth/token.go" line-rate="0.9183673" branch-rate="0" complexity="0" line-count="49" line-hits="45">
+					<methods>
+						<method name="init" signature="" line-rate="1" branch-rate="0" complexity="0" line-count="0" line-hits="0">
+							<lines>
+								<line number="38" hits="1"></line>
+							</lines>
+						</method>
+						<method name="CheckToken" signature="" line-rate="0.9285714" branch-rate="0" complexity="0" line-count="0" line-hits="0">
+							<lines>
+								<line number="52" hits="1"></line>
+								<line number="53" hits="0"></line>
+								<line number="56" hits="1"></line>
+								<line number="57" hits="1"></line>
+								<line number="58" hits="1"></line>
+								<line number="61" hits="1"></line>
+								<line number="63" hits="1"></line>
+								<line number="64" hits="1"></line>
+								<line number="65" hits="1"></line>
+								<line number="68" hits="1"></line>
+								<line number="69" hits="1"></line>
+								<line number="72" hits="1"></line>
+								<line number="73" hits="1"></line>
+								<line number="77" hits="1"></line>
+							</lines>
+						</method>
+						<method name="tokensEqual" signature="" line-rate="1" branch-rate="0" complexity="0" line-count="0" line-hits="0">
+							<lines>
+								<line number="81" hits="1"></line>
+							</lines>
+						</method>
+						<method name="ExtractAuthInfo" signature="" line-rate="0.90909094" branch-rate="0" complexity="0" line-count="0" line-hits="0">
+							<lines>
+								<line number="86" hits="1"></line>
+								<line number="88" hits="1"></line>
+								<line number="89" hits="1"></line>
+								<line number="92" hits="1"></line>
+								<line number="96" hits="1"></line>
+								<line number="97" hits="1"></line>
+								<line number="100" hits="1"></line>
+								<line number="101" hits="1"></line>
+								<line number="102" hits="1"></line>
+								<line number="103" hits="0"></line>
+								<line number="106" hits="1"></line>
+							</lines>
+						</method>
+						<method name="countV2Error" signature="" line-rate="1" branch-rate="0" complexity="0" line-count="0" line-hits="0">
+							<lines>
+								<line number="109" hits="1"></line>
+							</lines>
+						</method>
+						<method name="v2HmacInfoValid" signature="" line-rate="0.8888889" branch-rate="0" complexity="0" line-count="0" line-hits="0">
+							<lines>
+								<line number="112" hits="1"></line>
+								<line number="113" hits="1"></line>
+								<line number="114" hits="1"></line>
+								<line number="115" hits="1"></line>
+								<line number="118" hits="1"></line>
+								<line number="119" hits="1"></line>
+								<line number="120" hits="0"></line>
+								<line number="121" hits="0"></line>
+								<line number="124" hits="1"></line>
+								<line number="125" hits="1"></line>
+								<line number="126" hits="1"></line>
+								<line number="128" hits="1"></line>
+								<line number="129" hits="1"></line>
+								<line number="130" hits="1"></line>
+								<line number="133" hits="1"></line>
+								<line number="134" hits="1"></line>
+								<line number="135" hits="1"></line>
+								<line number="138" hits="1"></line>
+							</lines>
+						</method>
+						<method name="hmacSign" signature="" line-rate="1" branch-rate="0" complexity="0" line-count="0" line-hits="0">
+							<lines>
+								<line number="142" hits="1"></line>
+								<line number="143" hits="1"></line>
+								<line number="145" hits="1"></line>
+							</lines>
+						</method>
+					</methods>
+					<lines>
+						<line number="38" hits="1"></line>
+						<line number="52" hits="1"></line>
+						<line number="53" hits="0"></line>
+						<line number="56" hits="1"></line>
+						<line number="57" hits="1"></line>
+						<line number="58" hits="1"></line>
+						<line number="61" hits="1"></line>
+						<line number="63" hits="1"></line>
+						<line number="64" hits="1"></line>
+						<line number="65" hits="1"></line>
+						<line number="68" hits="1"></line>
+						<line number="69" hits="1"></line>
+						<line number="72" hits="1"></line>
+						<line number="73" hits="1"></line>
+						<line number="77" hits="1"></line>
+						<line number="81" hits="1"></line>
+						<line number="86" hits="1"></line>
+						<line number="88" hits="1"></line>
+						<line number="89" hits="1"></line>
+						<line number="92" hits="1"></line>
+						<line number="96" hits="1"></line>
+						<line number="97" hits="1"></line>
+						<line number="100" hits="1"></line>
+						<line number="101" hits="1"></line>
+						<line number="102" hits="1"></line>
+						<line number="103" hits="0"></line>
+						<line number="106" hits="1"></line>
+						<line number="109" hits="1"></line>
+						<line number="112" hits="1"></line>
+						<line number="113" hits="1"></line>
+						<line number="114" hits="1"></line>
+						<line number="115" hits="1"></line>
+						<line number="118" hits="1"></line>
+						<line number="119" hits="1"></line>
+						<line number="120" hits="0"></line>
+						<line number="121" hits="0"></line>
+						<line number="124" hits="1"></line>
+						<line number="125" hits="1"></line>
+						<line number="126" hits="1"></line>
+						<line number="128" hits="1"></line>
+						<line number="129" hits="1"></line>
+						<line number="130" hits="1"></line>
+						<line number="133" hits="1"></line>
+						<line number="134" hits="1"></line>
+						<line number="135" hits="1"></line>
+						<line number="138" hits="1"></line>
+						<line number="142" hits="1"></line>
+						<line number="143" hits="1"></line>
+						<line number="145" hits="1"></line>
+					</lines>
+				</class>
+			</classes>
+		</package>
+	</packages>
+	<sources>
+		<source>/tmp/projects/gitlab-ce/gitaly/src/gitlab.com/gitlab-org/gitaly</source>
+	</sources>
+</coverage>
diff --git a/spec/fixtures/cobertura/coverage_gocov_xml.xml.gz b/spec/fixtures/cobertura/coverage_gocov_xml.xml.gz
new file mode 100644
index 0000000000000..e51dc50c2edb6
Binary files /dev/null and b/spec/fixtures/cobertura/coverage_gocov_xml.xml.gz differ
diff --git a/spec/fixtures/cobertura/coverage_with_corrupted_data.xml b/spec/fixtures/cobertura/coverage_with_corrupted_data.xml
new file mode 100644
index 0000000000000..ab0973eba2829
--- /dev/null
+++ b/spec/fixtures/cobertura/coverage_with_corrupted_data.xml
@@ -0,0 +1,50 @@
+<?xml version="1.0" ?>
+<!DOCTYPE coverage SYSTEM "http://cobertura.sourceforge.net/xml/coverage-04.dtd">
+<!-- cobertura example file - generated by NYC - manually modified -->
+<coverage lines-valid="22" lines-covered="16" line-rate="0.7273000000000001" branches-valid="4" branches-covered="2" branch-rate="0.5" timestamp="1576756029756" complexity="0" version="0.1">
+  <sources>
+    <source>/tmp/projects/coverage-test</source>
+  </sources>
+  <packages>
+    <package name="coverage-test" line-rate="0.6842" branch-rate="0.5">
+      <classes>
+        <class name="index.js" filename="index.js" line-rate="0.6842" branch-rate="0.5">
+          <methods>
+            <method name="(anonymous_3)" hits="0" signature="()V">
+              <lines>
+                <line number="21" hits="0"/>
+              </lines>
+            </method>
+          </methods>
+          <lines>
+            <line number="21" hits="1" branch="false"/>
+            <line number="22" hits="0" branch="false"/>
+            <line number="25" hits="1" branch="true" condition-coverage="50% (1/2)"/>
+            <line number="26" hits="0" branch="false"/>
+            <line number="27" hits="0" branch="false"/>
+            <line number="28" hits="0" branch="false"/>
+            <line number="29" hits="0" branch="false"/>
+          </lines>
+        </class>
+      </classes>
+    </package>
+    <package name="coverage-test.lib.math" line-rate="1" branch-rate="1">
+      <classes>
+        <class name="add.js" filename="lib/math/add.js" line-rate="1" branch-rate="1">
+          <methods>
+            <method name="(anonymous_0)" hits="1" signature="()V">
+              <lines>
+                <line number="1" hits="1"/>
+              </lines>
+            </method>
+          </methods>
+          <lines>
+            <line null="test" hits="1" branch="false"/>
+            <line number="2" hits="1" branch="false"/>
+            <line number="3" hits="1" branch="false"/>
+          </lines>
+        </class>
+      </classes>
+    </package>
+  </packages>
+</coverage>
diff --git a/spec/fixtures/cobertura/coverage_with_corrupted_data.xml.gz b/spec/fixtures/cobertura/coverage_with_corrupted_data.xml.gz
new file mode 100644
index 0000000000000..4d06c42ba0b60
Binary files /dev/null and b/spec/fixtures/cobertura/coverage_with_corrupted_data.xml.gz differ
diff --git a/spec/frontend/create_cluster/eks_cluster/components/eks_cluster_configuration_form_spec.js b/spec/frontend/create_cluster/eks_cluster/components/eks_cluster_configuration_form_spec.js
index 25034dcf5add6..34d9ee733c404 100644
--- a/spec/frontend/create_cluster/eks_cluster/components/eks_cluster_configuration_form_spec.js
+++ b/spec/frontend/create_cluster/eks_cluster/components/eks_cluster_configuration_form_spec.js
@@ -13,6 +13,7 @@ localVue.use(Vuex);
 describe('EksClusterConfigurationForm', () => {
   let store;
   let actions;
+  let getters;
   let state;
   let rolesState;
   let regionsState;
@@ -29,8 +30,7 @@ describe('EksClusterConfigurationForm', () => {
   let securityGroupsActions;
   let vm;
 
-  beforeEach(() => {
-    state = eksClusterFormState();
+  const createStore = (config = {}) => {
     actions = {
       createCluster: jest.fn(),
       setClusterName: jest.fn(),
@@ -64,29 +64,44 @@ describe('EksClusterConfigurationForm', () => {
     securityGroupsActions = {
       fetchItems: jest.fn(),
     };
+    state = {
+      ...eksClusterFormState(),
+      ...config.initialState,
+    };
     rolesState = {
       ...clusterDropdownStoreState(),
+      ...config.rolesState,
     };
     regionsState = {
       ...clusterDropdownStoreState(),
+      ...config.regionsState,
     };
     vpcsState = {
       ...clusterDropdownStoreState(),
+      ...config.vpcsState,
     };
     subnetsState = {
       ...clusterDropdownStoreState(),
+      ...config.subnetsState,
     };
     keyPairsState = {
       ...clusterDropdownStoreState(),
+      ...config.keyPairsState,
     };
     securityGroupsState = {
       ...clusterDropdownStoreState(),
+      ...config.securityGroupsState,
     };
     instanceTypesState = {
       ...clusterDropdownStoreState(),
+      ...config.instanceTypesState,
+    };
+    getters = {
+      subnetValid: config?.getters?.subnetValid || (() => false),
     };
     store = new Vuex.Store({
       state,
+      getters,
       actions,
       modules: {
         vpcs: {
@@ -125,9 +140,29 @@ describe('EksClusterConfigurationForm', () => {
         },
       },
     });
-  });
+  };
 
-  beforeEach(() => {
+  const createValidStateStore = initialState => {
+    createStore({
+      initialState: {
+        clusterName: 'cluster name',
+        environmentScope: '*',
+        selectedRegion: 'region',
+        selectedRole: 'role',
+        selectedKeyPair: 'key pair',
+        selectedVpc: 'vpc',
+        selectedSubnet: ['subnet 1', 'subnet 2'],
+        selectedSecurityGroup: 'group',
+        selectedInstanceType: 'small-1',
+        ...initialState,
+      },
+      getters: {
+        subnetValid: () => true,
+      },
+    });
+  };
+
+  const buildWrapper = () => {
     vm = shallowMount(EksClusterConfigurationForm, {
       localVue,
       store,
@@ -137,27 +172,17 @@ describe('EksClusterConfigurationForm', () => {
         externalLinkIcon: '',
       },
     });
+  };
+
+  beforeEach(() => {
+    createStore();
+    buildWrapper();
   });
 
   afterEach(() => {
     vm.destroy();
   });
 
-  const setAllConfigurationFields = () => {
-    store.replaceState({
-      ...state,
-      clusterName: 'cluster name',
-      environmentScope: '*',
-      selectedRegion: 'region',
-      selectedRole: 'role',
-      selectedKeyPair: 'key pair',
-      selectedVpc: 'vpc',
-      selectedSubnet: 'subnet',
-      selectedSecurityGroup: 'group',
-      selectedInstanceType: 'small-1',
-    });
-  };
-
   const findCreateClusterButton = () => vm.find('.js-create-cluster');
   const findClusterNameInput = () => vm.find('[id=eks-cluster-name]');
   const findEnvironmentScopeInput = () => vm.find('[id=eks-environment-scope]');
@@ -310,12 +335,29 @@ describe('EksClusterConfigurationForm', () => {
     expect(findSubnetDropdown().props('items')).toBe(subnetsState.items);
   });
 
-  it('sets SubnetDropdown hasErrors to true when loading subnets fails', () => {
-    subnetsState.loadingItemsError = new Error();
+  it('displays a validation error in the subnet dropdown when loading subnets fails', () => {
+    createStore({
+      subnetsState: {
+        loadingItemsError: new Error(),
+      },
+    });
+    buildWrapper();
 
-    return Vue.nextTick().then(() => {
-      expect(findSubnetDropdown().props('hasErrors')).toEqual(true);
+    expect(findSubnetDropdown().props('hasErrors')).toEqual(true);
+  });
+
+  it('displays a validation error in the subnet dropdown  when a single subnet is selected', () => {
+    createStore({
+      initialState: {
+        selectedSubnet: ['subnet 1'],
+      },
     });
+    buildWrapper();
+
+    expect(findSubnetDropdown().props('hasErrors')).toEqual(true);
+    expect(findSubnetDropdown().props('errorMessage')).toEqual(
+      'You should select at least two subnets',
+    );
   });
 
   it('disables SecurityGroupDropdown when no vpc is selected', () => {
@@ -386,11 +428,7 @@ describe('EksClusterConfigurationForm', () => {
     });
 
     it('cleans selected subnet', () => {
-      expect(actions.setSubnet).toHaveBeenCalledWith(
-        expect.anything(),
-        { subnet: null },
-        undefined,
-      );
+      expect(actions.setSubnet).toHaveBeenCalledWith(expect.anything(), { subnet: [] }, undefined);
     });
 
     it('cleans selected security group', () => {
@@ -464,11 +502,7 @@ describe('EksClusterConfigurationForm', () => {
     });
 
     it('cleans selected subnet', () => {
-      expect(actions.setSubnet).toHaveBeenCalledWith(
-        expect.anything(),
-        { subnet: null },
-        undefined,
-      );
+      expect(actions.setSubnet).toHaveBeenCalledWith(expect.anything(), { subnet: [] }, undefined);
     });
 
     it('cleans selected security group', () => {
@@ -573,22 +607,19 @@ describe('EksClusterConfigurationForm', () => {
   });
 
   describe('when all cluster configuration fields are set', () => {
-    beforeEach(() => {
-      setAllConfigurationFields();
-    });
-
     it('enables create cluster button', () => {
+      createValidStateStore();
+      buildWrapper();
       expect(findCreateClusterButton().props('disabled')).toBe(false);
     });
   });
 
   describe('when at least one cluster configuration field is not set', () => {
     beforeEach(() => {
-      setAllConfigurationFields();
-      store.replaceState({
-        ...state,
-        clusterName: '',
+      createValidStateStore({
+        clusterName: null,
       });
+      buildWrapper();
     });
 
     it('disables create cluster button', () => {
@@ -596,13 +627,12 @@ describe('EksClusterConfigurationForm', () => {
     });
   });
 
-  describe('when isCreatingCluster', () => {
+  describe('when is creating cluster', () => {
     beforeEach(() => {
-      setAllConfigurationFields();
-      store.replaceState({
-        ...state,
+      createValidStateStore({
         isCreatingCluster: true,
       });
+      buildWrapper();
     });
 
     it('sets create cluster button as loading', () => {
diff --git a/spec/frontend/create_cluster/eks_cluster/store/getters_spec.js b/spec/frontend/create_cluster/eks_cluster/store/getters_spec.js
new file mode 100644
index 0000000000000..7c26aeb9b93cd
--- /dev/null
+++ b/spec/frontend/create_cluster/eks_cluster/store/getters_spec.js
@@ -0,0 +1,13 @@
+import { subnetValid } from '~/create_cluster/eks_cluster/store/getters';
+
+describe('EKS Cluster Store Getters', () => {
+  describe('subnetValid', () => {
+    it('returns true if there are 2 or more selected subnets', () => {
+      expect(subnetValid({ selectedSubnet: [1, 2] })).toBe(true);
+    });
+
+    it.each([[[], [1]]])('returns false if there are 1 or less selected subnets', subnets => {
+      expect(subnetValid({ selectedSubnet: subnets })).toBe(false);
+    });
+  });
+});
diff --git a/spec/frontend/diffs/components/app_spec.js b/spec/frontend/diffs/components/app_spec.js
index 15f918714373b..78e3ff4a60c2c 100644
--- a/spec/frontend/diffs/components/app_spec.js
+++ b/spec/frontend/diffs/components/app_spec.js
@@ -41,6 +41,7 @@ describe('diffs/components/app', () => {
         endpoint: TEST_ENDPOINT,
         endpointMetadata: `${TEST_HOST}/diff/endpointMetadata`,
         endpointBatch: `${TEST_HOST}/diff/endpointBatch`,
+        endpointCoverage: `${TEST_HOST}/diff/endpointCoverage`,
         projectPath: 'namespace/project',
         currentUser: {},
         changesEmptyStateIllustration: '',
@@ -95,6 +96,7 @@ describe('diffs/components/app', () => {
       jest.spyOn(wrapper.vm, 'fetchDiffFiles').mockImplementation(fetchResolver);
       jest.spyOn(wrapper.vm, 'fetchDiffFilesMeta').mockImplementation(fetchResolver);
       jest.spyOn(wrapper.vm, 'fetchDiffFilesBatch').mockImplementation(fetchResolver);
+      jest.spyOn(wrapper.vm, 'fetchCoverageFiles').mockImplementation(fetchResolver);
       jest.spyOn(wrapper.vm, 'setDiscussions').mockImplementation(() => {});
       jest.spyOn(wrapper.vm, 'startRenderDiffsQueue').mockImplementation(() => {});
       jest.spyOn(wrapper.vm, 'unwatchDiscussions').mockImplementation(() => {});
@@ -250,6 +252,7 @@ describe('diffs/components/app', () => {
         expect(wrapper.vm.startRenderDiffsQueue).toHaveBeenCalled();
         expect(wrapper.vm.fetchDiffFilesMeta).not.toHaveBeenCalled();
         expect(wrapper.vm.fetchDiffFilesBatch).not.toHaveBeenCalled();
+        expect(wrapper.vm.fetchCoverageFiles).toHaveBeenCalled();
         expect(wrapper.vm.unwatchDiscussions).toHaveBeenCalled();
         expect(wrapper.vm.diffFilesLength).toEqual(100);
         expect(wrapper.vm.unwatchRetrievingBatches).toHaveBeenCalled();
@@ -269,6 +272,7 @@ describe('diffs/components/app', () => {
         expect(wrapper.vm.startRenderDiffsQueue).toHaveBeenCalled();
         expect(wrapper.vm.fetchDiffFilesMeta).toHaveBeenCalled();
         expect(wrapper.vm.fetchDiffFilesBatch).toHaveBeenCalled();
+        expect(wrapper.vm.fetchCoverageFiles).toHaveBeenCalled();
         expect(wrapper.vm.unwatchDiscussions).toHaveBeenCalled();
         expect(wrapper.vm.diffFilesLength).toEqual(100);
         expect(wrapper.vm.unwatchRetrievingBatches).toHaveBeenCalled();
@@ -286,6 +290,7 @@ describe('diffs/components/app', () => {
         expect(wrapper.vm.startRenderDiffsQueue).toHaveBeenCalled();
         expect(wrapper.vm.fetchDiffFilesMeta).toHaveBeenCalled();
         expect(wrapper.vm.fetchDiffFilesBatch).toHaveBeenCalled();
+        expect(wrapper.vm.fetchCoverageFiles).toHaveBeenCalled();
         expect(wrapper.vm.unwatchDiscussions).toHaveBeenCalled();
         expect(wrapper.vm.diffFilesLength).toEqual(100);
         expect(wrapper.vm.unwatchRetrievingBatches).toHaveBeenCalled();
diff --git a/spec/javascripts/diffs/components/inline_diff_table_row_spec.js b/spec/javascripts/diffs/components/inline_diff_table_row_spec.js
index 67443e9aecc1d..392893eb6951b 100644
--- a/spec/javascripts/diffs/components/inline_diff_table_row_spec.js
+++ b/spec/javascripts/diffs/components/inline_diff_table_row_spec.js
@@ -12,6 +12,7 @@ describe('InlineDiffTableRow', () => {
     vm = createComponentWithStore(Vue.extend(InlineDiffTableRow), createStore(), {
       line: thisLine,
       fileHash: diffFileMockData.file_hash,
+      filePath: diffFileMockData.file_path,
       contextLinesPath: 'contextLinesPath',
       isHighlighted: false,
     }).$mount();
@@ -39,4 +40,64 @@ describe('InlineDiffTableRow', () => {
       .then(done)
       .catch(done.fail);
   });
+
+  describe('sets coverage title and class', () => {
+    it('for lines with coverage', done => {
+      vm.$nextTick()
+        .then(() => {
+          const name = diffFileMockData.file_path;
+          const line = thisLine.new_line;
+
+          vm.$store.state.diffs.coverageFiles = { files: { [name]: { [line]: 5 } } };
+
+          return vm.$nextTick();
+        })
+        .then(() => {
+          const coverage = vm.$el.querySelector('.line-coverage');
+
+          expect(coverage.title).toContain('Test coverage: 5 hits');
+          expect(coverage.classList).toContain('coverage');
+        })
+        .then(done)
+        .catch(done.fail);
+    });
+
+    it('for lines without coverage', done => {
+      vm.$nextTick()
+        .then(() => {
+          const name = diffFileMockData.file_path;
+          const line = thisLine.new_line;
+
+          vm.$store.state.diffs.coverageFiles = { files: { [name]: { [line]: 0 } } };
+
+          return vm.$nextTick();
+        })
+        .then(() => {
+          const coverage = vm.$el.querySelector('.line-coverage');
+
+          expect(coverage.title).toContain('No test coverage');
+          expect(coverage.classList).toContain('no-coverage');
+        })
+        .then(done)
+        .catch(done.fail);
+    });
+
+    it('for unknown lines', done => {
+      vm.$nextTick()
+        .then(() => {
+          vm.$store.state.diffs.coverageFiles = {};
+
+          return vm.$nextTick();
+        })
+        .then(() => {
+          const coverage = vm.$el.querySelector('.line-coverage');
+
+          expect(coverage.title).not.toContain('Coverage');
+          expect(coverage.classList).not.toContain('coverage');
+          expect(coverage.classList).not.toContain('no-coverage');
+        })
+        .then(done)
+        .catch(done.fail);
+    });
+  });
 });
diff --git a/spec/javascripts/diffs/components/parallel_diff_table_row_spec.js b/spec/javascripts/diffs/components/parallel_diff_table_row_spec.js
index 32c947bbd8e7c..4e69382ba0329 100644
--- a/spec/javascripts/diffs/components/parallel_diff_table_row_spec.js
+++ b/spec/javascripts/diffs/components/parallel_diff_table_row_spec.js
@@ -14,6 +14,7 @@ describe('ParallelDiffTableRow', () => {
       vm = createComponentWithStore(Vue.extend(ParallelDiffTableRow), createStore(), {
         line: thisLine,
         fileHash: diffFileMockData.file_hash,
+        filePath: diffFileMockData.file_path,
         contextLinesPath: 'contextLinesPath',
         isHighlighted: false,
       }).$mount();
@@ -52,6 +53,7 @@ describe('ParallelDiffTableRow', () => {
       vm = createComponentWithStore(Vue.extend(ParallelDiffTableRow), createStore(), {
         line: thisLine,
         fileHash: diffFileMockData.file_hash,
+        filePath: diffFileMockData.file_path,
         contextLinesPath: 'contextLinesPath',
         isHighlighted: false,
       }).$mount();
@@ -81,5 +83,65 @@ describe('ParallelDiffTableRow', () => {
         .then(done)
         .catch(done.fail);
     });
+
+    describe('sets coverage title and class', () => {
+      it('for lines with coverage', done => {
+        vm.$nextTick()
+          .then(() => {
+            const name = diffFileMockData.file_path;
+            const line = rightLine.new_line;
+
+            vm.$store.state.diffs.coverageFiles = { files: { [name]: { [line]: 5 } } };
+
+            return vm.$nextTick();
+          })
+          .then(() => {
+            const coverage = vm.$el.querySelector('.line-coverage.right-side');
+
+            expect(coverage.title).toContain('Test coverage: 5 hits');
+            expect(coverage.classList).toContain('coverage');
+          })
+          .then(done)
+          .catch(done.fail);
+      });
+
+      it('for lines without coverage', done => {
+        vm.$nextTick()
+          .then(() => {
+            const name = diffFileMockData.file_path;
+            const line = rightLine.new_line;
+
+            vm.$store.state.diffs.coverageFiles = { files: { [name]: { [line]: 0 } } };
+
+            return vm.$nextTick();
+          })
+          .then(() => {
+            const coverage = vm.$el.querySelector('.line-coverage.right-side');
+
+            expect(coverage.title).toContain('No test coverage');
+            expect(coverage.classList).toContain('no-coverage');
+          })
+          .then(done)
+          .catch(done.fail);
+      });
+
+      it('for unknown lines', done => {
+        vm.$nextTick()
+          .then(() => {
+            vm.$store.state.diffs.coverageFiles = {};
+
+            return vm.$nextTick();
+          })
+          .then(() => {
+            const coverage = vm.$el.querySelector('.line-coverage.right-side');
+
+            expect(coverage.title).not.toContain('Coverage');
+            expect(coverage.classList).not.toContain('coverage');
+            expect(coverage.classList).not.toContain('no-coverage');
+          })
+          .then(done)
+          .catch(done.fail);
+      });
+    });
   });
 });
diff --git a/spec/javascripts/diffs/store/actions_spec.js b/spec/javascripts/diffs/store/actions_spec.js
index ff17d8ec15802..7363a2138478d 100644
--- a/spec/javascripts/diffs/store/actions_spec.js
+++ b/spec/javascripts/diffs/store/actions_spec.js
@@ -12,6 +12,7 @@ import actions, {
   fetchDiffFiles,
   fetchDiffFilesBatch,
   fetchDiffFilesMeta,
+  fetchCoverageFiles,
   assignDiscussionsToDiff,
   removeDiscussionsFromDiff,
   startRenderDiffsQueue,
@@ -73,6 +74,7 @@ describe('DiffsStoreActions', () => {
       const endpoint = '/diffs/set/endpoint';
       const endpointMetadata = '/diffs/set/endpoint/metadata';
       const endpointBatch = '/diffs/set/endpoint/batch';
+      const endpointCoverage = '/diffs/set/coverage_reports';
       const projectPath = '/root/project';
       const dismissEndpoint = '/-/user_callouts';
       const showSuggestPopover = false;
@@ -84,6 +86,7 @@ describe('DiffsStoreActions', () => {
           endpoint,
           endpointBatch,
           endpointMetadata,
+          endpointCoverage,
           projectPath,
           dismissEndpoint,
           showSuggestPopover,
@@ -93,6 +96,7 @@ describe('DiffsStoreActions', () => {
           endpoint: '',
           endpointBatch: '',
           endpointMetadata: '',
+          endpointCoverage: '',
           projectPath: '',
           dismissEndpoint: '',
           showSuggestPopover: true,
@@ -105,6 +109,7 @@ describe('DiffsStoreActions', () => {
               endpoint,
               endpointMetadata,
               endpointBatch,
+              endpointCoverage,
               projectPath,
               dismissEndpoint,
               showSuggestPopover,
@@ -318,6 +323,44 @@ describe('DiffsStoreActions', () => {
     });
   });
 
+  describe('fetchCoverageFiles', () => {
+    let mock;
+    const endpointCoverage = '/fetch';
+
+    beforeEach(() => {
+      mock = new MockAdapter(axios);
+    });
+
+    afterEach(() => mock.restore());
+
+    it('should commit SET_COVERAGE_DATA with received response', done => {
+      const data = { files: { 'app.js': { '1': 0, '2': 1 } } };
+
+      mock.onGet(endpointCoverage).reply(200, { data });
+
+      testAction(
+        fetchCoverageFiles,
+        {},
+        { endpointCoverage },
+        [{ type: types.SET_COVERAGE_DATA, payload: { data } }],
+        [],
+        done,
+      );
+    });
+
+    it('should show flash on API error', done => {
+      const flashSpy = spyOnDependency(actions, 'createFlash');
+
+      mock.onGet(endpointCoverage).reply(400);
+
+      testAction(fetchCoverageFiles, {}, { endpointCoverage }, [], [], () => {
+        expect(flashSpy).toHaveBeenCalledTimes(1);
+        expect(flashSpy).toHaveBeenCalledWith(jasmine.stringMatching('Something went wrong'));
+        done();
+      });
+    });
+  });
+
   describe('setHighlightedRow', () => {
     it('should mark currently selected diff and set lineHash and fileHash of highlightedRow', () => {
       testAction(setHighlightedRow, 'ABC_123', {}, [
diff --git a/spec/javascripts/diffs/store/getters_spec.js b/spec/javascripts/diffs/store/getters_spec.js
index 9e628fdd540e1..ca47f51cb1550 100644
--- a/spec/javascripts/diffs/store/getters_spec.js
+++ b/spec/javascripts/diffs/store/getters_spec.js
@@ -282,4 +282,34 @@ describe('Diffs Module Getters', () => {
       expect(getters.currentDiffIndex(localState)).toEqual(0);
     });
   });
+
+  describe('fileLineCoverage', () => {
+    beforeEach(() => {
+      Object.assign(localState.coverageFiles, { files: { 'app.js': { '1': 0, '2': 5 } } });
+    });
+
+    it('returns empty object when no coverage data is available', () => {
+      Object.assign(localState.coverageFiles, {});
+
+      expect(getters.fileLineCoverage(localState)('test.js', 2)).toEqual({});
+    });
+
+    it('returns empty object when unknown filename is passed', () => {
+      expect(getters.fileLineCoverage(localState)('test.js', 2)).toEqual({});
+    });
+
+    it('returns no-coverage info when correct filename and line is passed', () => {
+      expect(getters.fileLineCoverage(localState)('app.js', 1)).toEqual({
+        text: 'No test coverage',
+        class: 'no-coverage',
+      });
+    });
+
+    it('returns coverage info when correct filename and line is passed', () => {
+      expect(getters.fileLineCoverage(localState)('app.js', 2)).toEqual({
+        text: 'Test coverage: 5 hits',
+        class: 'coverage',
+      });
+    });
+  });
 });
diff --git a/spec/javascripts/diffs/store/mutations_spec.js b/spec/javascripts/diffs/store/mutations_spec.js
index ffe5d89e615ef..c36aff39aa950 100644
--- a/spec/javascripts/diffs/store/mutations_spec.js
+++ b/spec/javascripts/diffs/store/mutations_spec.js
@@ -123,6 +123,17 @@ describe('DiffsStoreMutations', () => {
     });
   });
 
+  describe('SET_COVERAGE_DATA', () => {
+    it('should set coverage data properly', () => {
+      const state = { coverageFiles: {} };
+      const coverage = { 'app.js': { '1': 0, '2': 1 } };
+
+      mutations[types.SET_COVERAGE_DATA](state, coverage);
+
+      expect(state.coverageFiles).toEqual(coverage);
+    });
+  });
+
   describe('SET_DIFF_VIEW_TYPE', () => {
     it('should set diff view type properly', () => {
       const state = {};
diff --git a/spec/lib/gitlab/ci/config/entry/reports_spec.rb b/spec/lib/gitlab/ci/config/entry/reports_spec.rb
index 31e1aaa42bf40..2c8f76c8f343f 100644
--- a/spec/lib/gitlab/ci/config/entry/reports_spec.rb
+++ b/spec/lib/gitlab/ci/config/entry/reports_spec.rb
@@ -45,6 +45,7 @@
         :performance | 'performance.json'
         :lsif | 'lsif.json'
         :dotenv | 'build.dotenv'
+        :cobertura | 'cobertura-coverage.xml'
       end
 
       with_them do
diff --git a/spec/lib/gitlab/ci/parsers/coverage/cobertura_spec.rb b/spec/lib/gitlab/ci/parsers/coverage/cobertura_spec.rb
new file mode 100644
index 0000000000000..e97544683db29
--- /dev/null
+++ b/spec/lib/gitlab/ci/parsers/coverage/cobertura_spec.rb
@@ -0,0 +1,176 @@
+# frozen_string_literal: true
+
+require 'fast_spec_helper'
+
+describe Gitlab::Ci::Parsers::Coverage::Cobertura do
+  describe '#parse!' do
+    subject { described_class.new.parse!(cobertura, coverage_report) }
+
+    let(:coverage_report) { Gitlab::Ci::Reports::CoverageReports.new }
+
+    context 'when data is Cobertura style XML' do
+      context 'when there is no <class>' do
+        let(:cobertura) { '' }
+
+        it 'parses XML and returns empty coverage' do
+          expect { subject }.not_to raise_error
+
+          expect(coverage_report.files).to eq({})
+        end
+      end
+
+      context 'when there is a single <class>' do
+        context 'with no lines' do
+          let(:cobertura) do
+            <<-EOF.strip_heredoc
+            <classes><class filename="app.rb"></class></classes>
+            EOF
+          end
+
+          it 'parses XML and returns empty coverage' do
+            expect { subject }.not_to raise_error
+
+            expect(coverage_report.files).to eq({})
+          end
+        end
+
+        context 'with a single line' do
+          let(:cobertura) do
+            <<-EOF.strip_heredoc
+            <classes>
+              <class filename="app.rb"><lines>
+                <line number="1" hits="2"/>
+              </lines></class>
+            </classes>
+            EOF
+          end
+
+          it 'parses XML and returns a single file with coverage' do
+            expect { subject }.not_to raise_error
+
+            expect(coverage_report.files).to eq({ 'app.rb' => { 1 => 2 } })
+          end
+        end
+
+        context 'with multipe lines and methods info' do
+          let(:cobertura) do
+            <<-EOF.strip_heredoc
+            <classes>
+              <class filename="app.rb"><methods/><lines>
+                <line number="1" hits="2"/>
+                <line number="2" hits="0"/>
+              </lines></class>
+            </classes>
+            EOF
+          end
+
+          it 'parses XML and returns a single file with coverage' do
+            expect { subject }.not_to raise_error
+
+            expect(coverage_report.files).to eq({ 'app.rb' => { 1 => 2, 2 => 0 } })
+          end
+        end
+      end
+
+      context 'when there are multipe <class>' do
+        context 'with the same filename and different lines' do
+          let(:cobertura) do
+            <<-EOF.strip_heredoc
+            <classes>
+              <class filename="app.rb"><methods/><lines>
+                <line number="1" hits="2"/>
+                <line number="2" hits="0"/>
+              </lines></class>
+              <class filename="app.rb"><methods/><lines>
+                <line number="6" hits="1"/>
+                <line number="7" hits="1"/>
+              </lines></class>
+            </classes>
+            EOF
+          end
+
+          it 'parses XML and returns a single file with merged coverage' do
+            expect { subject }.not_to raise_error
+
+            expect(coverage_report.files).to eq({ 'app.rb' => { 1 => 2, 2 => 0, 6 => 1, 7 => 1 } })
+          end
+        end
+
+        context 'with the same filename and lines' do
+          let(:cobertura) do
+            <<-EOF.strip_heredoc
+            <packages><package><classes>
+              <class filename="app.rb"><methods/><lines>
+                <line number="1" hits="2"/>
+                <line number="2" hits="0"/>
+              </lines></class>
+              <class filename="app.rb"><methods/><lines>
+                <line number="1" hits="1"/>
+                <line number="2" hits="1"/>
+              </lines></class>
+            </classes></package></packages>
+            EOF
+          end
+
+          it 'parses XML and returns a single file with summed-up coverage' do
+            expect { subject }.not_to raise_error
+
+            expect(coverage_report.files).to eq({ 'app.rb' => { 1 => 3, 2 => 1 } })
+          end
+        end
+
+        context 'with missing filename' do
+          let(:cobertura) do
+            <<-EOF.strip_heredoc
+            <classes>
+              <class filename="app.rb"><methods/><lines>
+                <line number="1" hits="2"/>
+                <line number="2" hits="0"/>
+              </lines></class>
+              <class><methods/><lines>
+                <line number="6" hits="1"/>
+                <line number="7" hits="1"/>
+              </lines></class>
+            </classes>
+            EOF
+          end
+
+          it 'parses XML and ignores class with missing name' do
+            expect { subject }.not_to raise_error
+
+            expect(coverage_report.files).to eq({ 'app.rb' => { 1 => 2, 2 => 0 } })
+          end
+        end
+
+        context 'with invalid line information' do
+          let(:cobertura) do
+            <<-EOF.strip_heredoc
+            <classes>
+              <class filename="app.rb"><methods/><lines>
+                <line number="1" hits="2"/>
+                <line number="2" hits="0"/>
+              </lines></class>
+              <class filename="app.rb"><methods/><lines>
+                <line null="test" hits="1"/>
+                <line number="7" hits="1"/>
+              </lines></class>
+            </classes>
+            EOF
+          end
+
+          it 'raises an error' do
+            expect { subject }.to raise_error(described_class::CoberturaParserError)
+          end
+        end
+      end
+    end
+
+    context 'when data is not Cobertura style XML' do
+      let(:cobertura) { { coverage: '12%' }.to_json }
+
+      it 'raises an error' do
+        expect { subject }.to raise_error(described_class::CoberturaParserError)
+      end
+    end
+  end
+end
diff --git a/spec/lib/gitlab/ci/parsers_spec.rb b/spec/lib/gitlab/ci/parsers_spec.rb
index 4b647bffe59c2..9d6896b3cb452 100644
--- a/spec/lib/gitlab/ci/parsers_spec.rb
+++ b/spec/lib/gitlab/ci/parsers_spec.rb
@@ -6,7 +6,7 @@
   describe '.fabricate!' do
     subject { described_class.fabricate!(file_type) }
 
-    context 'when file_type exists' do
+    context 'when file_type is junit' do
       let(:file_type) { 'junit' }
 
       it 'fabricates the class' do
@@ -14,6 +14,14 @@
       end
     end
 
+    context 'when file_type is cobertura' do
+      let(:file_type) { 'cobertura' }
+
+      it 'fabricates the class' do
+        is_expected.to be_a(described_class::Coverage::Cobertura)
+      end
+    end
+
     context 'when file_type does not exist' do
       let(:file_type) { 'undefined' }
 
diff --git a/spec/lib/gitlab/ci/reports/coverage_reports_spec.rb b/spec/lib/gitlab/ci/reports/coverage_reports_spec.rb
new file mode 100644
index 0000000000000..7cf43ceab324f
--- /dev/null
+++ b/spec/lib/gitlab/ci/reports/coverage_reports_spec.rb
@@ -0,0 +1,66 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Gitlab::Ci::Reports::CoverageReports do
+  let(:coverage_report) { described_class.new }
+
+  it { expect(coverage_report.files).to eq({}) }
+
+  describe '#pick' do
+    before do
+      coverage_report.add_file('app.rb', { 1 => 0, 2 => 1 })
+      coverage_report.add_file('routes.rb', { 3 => 1, 4 => 0 })
+    end
+
+    it 'returns only picked files while ignoring nonexistent ones' do
+      expect(coverage_report.pick(['routes.rb', 'nonexistent.txt'])).to eq({
+        files: { 'routes.rb' => { 3 => 1, 4 => 0 } }
+      })
+    end
+  end
+
+  describe '#add_file' do
+    context 'when providing two individual files' do
+      before do
+        coverage_report.add_file('app.rb', { 1 => 0, 2 => 1 })
+        coverage_report.add_file('routes.rb', { 3 => 1, 4 => 0 })
+      end
+
+      it 'initializes a new test suite and returns it' do
+        expect(coverage_report.files).to eq({
+          'app.rb' => { 1 => 0, 2 => 1 },
+          'routes.rb' => { 3 => 1, 4 => 0 }
+        })
+      end
+    end
+
+    context 'when providing the same files twice' do
+      context 'with different line coverage' do
+        before do
+          coverage_report.add_file('admin.rb', { 1 => 0, 2 => 1 })
+          coverage_report.add_file('admin.rb', { 3 => 1, 4 => 0 })
+        end
+
+        it 'initializes a new test suite and returns it' do
+          expect(coverage_report.files).to eq({
+            'admin.rb' => { 1 => 0, 2 => 1, 3 => 1, 4 => 0 }
+          })
+        end
+      end
+
+      context 'with identical line coverage' do
+        before do
+          coverage_report.add_file('projects.rb', { 1 => 0, 2 => 1 })
+          coverage_report.add_file('projects.rb', { 1 => 0, 2 => 1 })
+        end
+
+        it 'initializes a new test suite and returns it' do
+          expect(coverage_report.files).to eq({
+            'projects.rb' => { 1 => 0, 2 => 2 }
+          })
+        end
+      end
+    end
+  end
+end
diff --git a/spec/lib/gitlab/import_export/group/tree_saver_spec.rb b/spec/lib/gitlab/import_export/group/tree_saver_spec.rb
index a7440ac24ca1d..44fd49f0ac3f1 100644
--- a/spec/lib/gitlab/import_export/group/tree_saver_spec.rb
+++ b/spec/lib/gitlab/import_export/group/tree_saver_spec.rb
@@ -197,6 +197,6 @@ def setup_group
   end
 
   def group_json(filename)
-    JSON.parse(IO.read(filename))
+    ::JSON.parse(IO.read(filename))
   end
 end
diff --git a/spec/lib/gitlab/import_export/json/legacy_writer_spec.rb b/spec/lib/gitlab/import_export/json/legacy_writer_spec.rb
new file mode 100644
index 0000000000000..b4cdfee3b221b
--- /dev/null
+++ b/spec/lib/gitlab/import_export/json/legacy_writer_spec.rb
@@ -0,0 +1,79 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Gitlab::ImportExport::JSON::LegacyWriter do
+  let(:path) { "#{Dir.tmpdir}/legacy_writer_spec/test.json" }
+
+  subject { described_class.new(path) }
+
+  after do
+    FileUtils.rm_rf(path)
+  end
+
+  describe "#write" do
+    context "when key is already written" do
+      it "raises exception" do
+        key = "key"
+        value = "value"
+        subject.write(key, value)
+
+        expect { subject.write(key, "new value") }.to raise_exception("key '#{key}' already written")
+      end
+    end
+
+    context "when key is not already written" do
+      context "when multiple key value pairs are stored" do
+        it "writes correct json" do
+          expected_hash = { "key" => "value_1", "key_1" => "value_2" }
+          expected_hash.each do |key, value|
+            subject.write(key, value)
+          end
+          subject.close
+
+          expect(saved_json(path)).to eq(expected_hash)
+        end
+      end
+    end
+  end
+
+  describe "#append" do
+    context "when key is already written" do
+      it "appends values under a given key" do
+        key = "key"
+        values = %w(value_1 value_2)
+        expected_hash = { key => values }
+        values.each do |value|
+          subject.append(key, value)
+        end
+        subject.close
+
+        expect(saved_json(path)).to eq(expected_hash)
+      end
+    end
+
+    context "when key is not already written" do
+      it "writes correct json" do
+        expected_hash = { "key" => ["value"] }
+        subject.append("key", "value")
+        subject.close
+
+        expect(saved_json(path)).to eq(expected_hash)
+      end
+    end
+  end
+
+  describe "#set" do
+    it "writes correct json" do
+      expected_hash = { "key" => "value_1", "key_1" => "value_2" }
+      subject.set(expected_hash)
+      subject.close
+
+      expect(saved_json(path)).to eq(expected_hash)
+    end
+  end
+
+  def saved_json(filename)
+    ::JSON.parse(IO.read(filename))
+  end
+end
diff --git a/spec/lib/gitlab/import_export/relation_tree_saver_spec.rb b/spec/lib/gitlab/import_export/legacy_relation_tree_saver_spec.rb
similarity index 94%
rename from spec/lib/gitlab/import_export/relation_tree_saver_spec.rb
rename to spec/lib/gitlab/import_export/legacy_relation_tree_saver_spec.rb
index 2fc26c0e3d48e..db77bd338e1ed 100644
--- a/spec/lib/gitlab/import_export/relation_tree_saver_spec.rb
+++ b/spec/lib/gitlab/import_export/legacy_relation_tree_saver_spec.rb
@@ -2,7 +2,7 @@
 
 require 'spec_helper'
 
-describe Gitlab::ImportExport::RelationTreeSaver do
+describe Gitlab::ImportExport::LegacyRelationTreeSaver do
   let(:exportable) { create(:group) }
   let(:relation_tree_saver) { described_class.new }
   let(:tree) { {} }
diff --git a/spec/lib/gitlab/import_export/project/legacy_tree_saver_spec.rb b/spec/lib/gitlab/import_export/project/legacy_tree_saver_spec.rb
new file mode 100644
index 0000000000000..d4406dbc60b7d
--- /dev/null
+++ b/spec/lib/gitlab/import_export/project/legacy_tree_saver_spec.rb
@@ -0,0 +1,397 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Gitlab::ImportExport::Project::LegacyTreeSaver do
+  describe 'saves the project tree into a json object' do
+    let(:shared) { project.import_export_shared }
+    let(:project_tree_saver) { described_class.new(project: project, current_user: user, shared: shared) }
+    let(:export_path) { "#{Dir.tmpdir}/project_tree_saver_spec" }
+    let(:user) { create(:user) }
+    let!(:project) { setup_project }
+
+    before do
+      project.add_maintainer(user)
+      allow_any_instance_of(Gitlab::ImportExport).to receive(:storage_path).and_return(export_path)
+      allow_any_instance_of(MergeRequest).to receive(:source_branch_sha).and_return('ABCD')
+      allow_any_instance_of(MergeRequest).to receive(:target_branch_sha).and_return('DCBA')
+    end
+
+    after do
+      FileUtils.rm_rf(export_path)
+    end
+
+    it 'saves project successfully' do
+      expect(project_tree_saver.save).to be true
+    end
+
+    context ':export_fast_serialize feature flag checks' do
+      before do
+        expect(Gitlab::ImportExport::Reader).to receive(:new).with(shared: shared).and_return(reader)
+        expect(reader).to receive(:project_tree).and_return(project_tree)
+      end
+
+      let(:serializer) { instance_double('Gitlab::ImportExport::FastHashSerializer') }
+      let(:reader) { instance_double('Gitlab::ImportExport::Reader') }
+      let(:project_tree) do
+        {
+          include: [{ issues: { include: [] } }],
+          preload: { issues: nil }
+        }
+      end
+
+      context 'when :export_fast_serialize feature is enabled' do
+        before do
+          stub_feature_flags(export_fast_serialize: true)
+        end
+
+        it 'uses FastHashSerializer' do
+          expect(Gitlab::ImportExport::FastHashSerializer)
+            .to receive(:new)
+            .with(project, project_tree)
+            .and_return(serializer)
+
+          expect(serializer).to receive(:execute)
+
+          project_tree_saver.save
+        end
+      end
+
+      context 'when :export_fast_serialize feature is disabled' do
+        before do
+          stub_feature_flags(export_fast_serialize: false)
+        end
+
+        it 'is serialized via built-in `as_json`' do
+          expect(project).to receive(:as_json).with(project_tree)
+
+          project_tree_saver.save
+        end
+      end
+    end
+
+    # It is mostly duplicated in
+    # `spec/lib/gitlab/import_export/fast_hash_serializer_spec.rb`
+    # except:
+    # context 'with description override' do
+    # context 'group members' do
+    # ^ These are specific for the Project::TreeSaver
+    context 'JSON' do
+      let(:saved_project_json) do
+        project_tree_saver.save
+        project_json(project_tree_saver.full_path)
+      end
+
+      # It is not duplicated in
+      # `spec/lib/gitlab/import_export/fast_hash_serializer_spec.rb`
+      context 'with description override' do
+        let(:params) { { description: 'Foo Bar' } }
+        let(:project_tree_saver) { described_class.new(project: project, current_user: user, shared: shared, params: params) }
+
+        it 'overrides the project description' do
+          expect(saved_project_json).to include({ 'description' => params[:description] })
+        end
+      end
+
+      it 'saves the correct json' do
+        expect(saved_project_json).to include({ 'description' => 'description', 'visibility_level' => 20 })
+      end
+
+      it 'has approvals_before_merge set' do
+        expect(saved_project_json['approvals_before_merge']).to eq(1)
+      end
+
+      it 'has milestones' do
+        expect(saved_project_json['milestones']).not_to be_empty
+      end
+
+      it 'has merge requests' do
+        expect(saved_project_json['merge_requests']).not_to be_empty
+      end
+
+      it 'has merge request\'s milestones' do
+        expect(saved_project_json['merge_requests'].first['milestone']).not_to be_empty
+      end
+
+      it 'has merge request\'s source branch SHA' do
+        expect(saved_project_json['merge_requests'].first['source_branch_sha']).to eq('ABCD')
+      end
+
+      it 'has merge request\'s target branch SHA' do
+        expect(saved_project_json['merge_requests'].first['target_branch_sha']).to eq('DCBA')
+      end
+
+      it 'has events' do
+        expect(saved_project_json['merge_requests'].first['milestone']['events']).not_to be_empty
+      end
+
+      it 'has snippets' do
+        expect(saved_project_json['snippets']).not_to be_empty
+      end
+
+      it 'has snippet notes' do
+        expect(saved_project_json['snippets'].first['notes']).not_to be_empty
+      end
+
+      it 'has releases' do
+        expect(saved_project_json['releases']).not_to be_empty
+      end
+
+      it 'has no author on releases' do
+        expect(saved_project_json['releases'].first['author']).to be_nil
+      end
+
+      it 'has the author ID on releases' do
+        expect(saved_project_json['releases'].first['author_id']).not_to be_nil
+      end
+
+      it 'has issues' do
+        expect(saved_project_json['issues']).not_to be_empty
+      end
+
+      it 'has issue comments' do
+        notes = saved_project_json['issues'].first['notes']
+
+        expect(notes).not_to be_empty
+        expect(notes.first['type']).to eq('DiscussionNote')
+      end
+
+      it 'has issue assignees' do
+        expect(saved_project_json['issues'].first['issue_assignees']).not_to be_empty
+      end
+
+      it 'has author on issue comments' do
+        expect(saved_project_json['issues'].first['notes'].first['author']).not_to be_empty
+      end
+
+      it 'has project members' do
+        expect(saved_project_json['project_members']).not_to be_empty
+      end
+
+      it 'has merge requests diffs' do
+        expect(saved_project_json['merge_requests'].first['merge_request_diff']).not_to be_empty
+      end
+
+      it 'has merge request diff files' do
+        expect(saved_project_json['merge_requests'].first['merge_request_diff']['merge_request_diff_files']).not_to be_empty
+      end
+
+      it 'has merge request diff commits' do
+        expect(saved_project_json['merge_requests'].first['merge_request_diff']['merge_request_diff_commits']).not_to be_empty
+      end
+
+      it 'has merge requests comments' do
+        expect(saved_project_json['merge_requests'].first['notes']).not_to be_empty
+      end
+
+      it 'has author on merge requests comments' do
+        expect(saved_project_json['merge_requests'].first['notes'].first['author']).not_to be_empty
+      end
+
+      it 'has pipeline stages' do
+        expect(saved_project_json.dig('ci_pipelines', 0, 'stages')).not_to be_empty
+      end
+
+      it 'has pipeline statuses' do
+        expect(saved_project_json.dig('ci_pipelines', 0, 'stages', 0, 'statuses')).not_to be_empty
+      end
+
+      it 'has pipeline builds' do
+        builds_count = saved_project_json
+          .dig('ci_pipelines', 0, 'stages', 0, 'statuses')
+          .count { |hash| hash['type'] == 'Ci::Build' }
+
+        expect(builds_count).to eq(1)
+      end
+
+      it 'has no when YML attributes but only the DB column' do
+        expect_any_instance_of(Gitlab::Ci::YamlProcessor).not_to receive(:build_attributes)
+
+        saved_project_json
+      end
+
+      it 'has pipeline commits' do
+        expect(saved_project_json['ci_pipelines']).not_to be_empty
+      end
+
+      it 'has ci pipeline notes' do
+        expect(saved_project_json['ci_pipelines'].first['notes']).not_to be_empty
+      end
+
+      it 'has labels with no associations' do
+        expect(saved_project_json['labels']).not_to be_empty
+      end
+
+      it 'has labels associated to records' do
+        expect(saved_project_json['issues'].first['label_links'].first['label']).not_to be_empty
+      end
+
+      it 'has project and group labels' do
+        label_types = saved_project_json['issues'].first['label_links'].map { |link| link['label']['type'] }
+
+        expect(label_types).to match_array(%w(ProjectLabel GroupLabel))
+      end
+
+      it 'has priorities associated to labels' do
+        priorities = saved_project_json['issues'].first['label_links'].flat_map { |link| link['label']['priorities'] }
+
+        expect(priorities).not_to be_empty
+      end
+
+      it 'has issue resource label events' do
+        expect(saved_project_json['issues'].first['resource_label_events']).not_to be_empty
+      end
+
+      it 'has merge request resource label events' do
+        expect(saved_project_json['merge_requests'].first['resource_label_events']).not_to be_empty
+      end
+
+      it 'saves the correct service type' do
+        expect(saved_project_json['services'].first['type']).to eq('CustomIssueTrackerService')
+      end
+
+      it 'saves the properties for a service' do
+        expect(saved_project_json['services'].first['properties']).to eq('one' => 'value')
+      end
+
+      it 'has project feature' do
+        project_feature = saved_project_json['project_feature']
+        expect(project_feature).not_to be_empty
+        expect(project_feature["issues_access_level"]).to eq(ProjectFeature::DISABLED)
+        expect(project_feature["wiki_access_level"]).to eq(ProjectFeature::ENABLED)
+        expect(project_feature["builds_access_level"]).to eq(ProjectFeature::PRIVATE)
+      end
+
+      it 'has custom attributes' do
+        expect(saved_project_json['custom_attributes'].count).to eq(2)
+      end
+
+      it 'has badges' do
+        expect(saved_project_json['project_badges'].count).to eq(2)
+      end
+
+      it 'does not complain about non UTF-8 characters in MR diff files' do
+        ActiveRecord::Base.connection.execute("UPDATE merge_request_diff_files SET diff = '---\n- :diff: !binary |-\n    LS0tIC9kZXYvbnVsbAorKysgYi9pbWFnZXMvbnVjb3IucGRmCkBAIC0wLDAg\n    KzEsMTY3OSBAQAorJVBERi0xLjUNJeLjz9MNCisxIDAgb2JqDTw8L01ldGFk\n    YXR'")
+
+        expect(project_tree_saver.save).to be true
+      end
+
+      context 'group members' do
+        let(:user2) { create(:user, email: 'group@member.com') }
+        let(:member_emails) do
+          saved_project_json['project_members'].map do |pm|
+            pm['user']['email']
+          end
+        end
+
+        before do
+          Group.first.add_developer(user2)
+        end
+
+        it 'does not export group members if it has no permission' do
+          Group.first.add_developer(user)
+
+          expect(member_emails).not_to include('group@member.com')
+        end
+
+        it 'does not export group members as maintainer' do
+          Group.first.add_maintainer(user)
+
+          expect(member_emails).not_to include('group@member.com')
+        end
+
+        it 'exports group members as group owner' do
+          Group.first.add_owner(user)
+
+          expect(member_emails).to include('group@member.com')
+        end
+
+        context 'as admin' do
+          let(:user) { create(:admin) }
+
+          it 'exports group members as admin' do
+            expect(member_emails).to include('group@member.com')
+          end
+
+          it 'exports group members as project members' do
+            member_types = saved_project_json['project_members'].map { |pm| pm['source_type'] }
+
+            expect(member_types).to all(eq('Project'))
+          end
+        end
+      end
+
+      context 'project attributes' do
+        it 'does not contain the runners token' do
+          expect(saved_project_json).not_to include("runners_token" => 'token')
+        end
+      end
+
+      it 'has a board and a list' do
+        expect(saved_project_json['boards'].first['lists']).not_to be_empty
+      end
+    end
+  end
+
+  def setup_project
+    release = create(:release)
+    group = create(:group)
+
+    project = create(:project,
+                     :public,
+                     :repository,
+                     :issues_disabled,
+                     :wiki_enabled,
+                     :builds_private,
+                     description: 'description',
+                     releases: [release],
+                     group: group,
+                     approvals_before_merge: 1
+                    )
+    allow(project).to receive(:commit).and_return(Commit.new(RepoHelpers.sample_commit, project))
+
+    issue = create(:issue, assignees: [user], project: project)
+    snippet = create(:project_snippet, project: project)
+    project_label = create(:label, project: project)
+    group_label = create(:group_label, group: group)
+    create(:label_link, label: project_label, target: issue)
+    create(:label_link, label: group_label, target: issue)
+    create(:label_priority, label: group_label, priority: 1)
+    milestone = create(:milestone, project: project)
+    merge_request = create(:merge_request, source_project: project, milestone: milestone)
+
+    ci_build = create(:ci_build, project: project, when: nil)
+    ci_build.pipeline.update(project: project)
+    create(:commit_status, project: project, pipeline: ci_build.pipeline)
+
+    create(:milestone, project: project)
+    create(:discussion_note, noteable: issue, project: project)
+    create(:note, noteable: merge_request, project: project)
+    create(:note, noteable: snippet, project: project)
+    create(:note_on_commit,
+           author: user,
+           project: project,
+           commit_id: ci_build.pipeline.sha)
+
+    create(:resource_label_event, label: project_label, issue: issue)
+    create(:resource_label_event, label: group_label, merge_request: merge_request)
+
+    create(:event, :created, target: milestone, project: project, author: user)
+    create(:service, project: project, type: 'CustomIssueTrackerService', category: 'issue_tracker', properties: { one: 'value' })
+
+    create(:project_custom_attribute, project: project)
+    create(:project_custom_attribute, project: project)
+
+    create(:project_badge, project: project)
+    create(:project_badge, project: project)
+
+    board = create(:board, project: project, name: 'TestBoard')
+    create(:list, board: board, position: 0, label: project_label)
+
+    project
+  end
+
+  def project_json(filename)
+    ::JSON.parse(IO.read(filename))
+  end
+end
diff --git a/spec/lib/gitlab/import_export/project/tree_saver_spec.rb b/spec/lib/gitlab/import_export/project/tree_saver_spec.rb
index 151fdf8810f67..23360b725b9ec 100644
--- a/spec/lib/gitlab/import_export/project/tree_saver_spec.rb
+++ b/spec/lib/gitlab/import_export/project/tree_saver_spec.rb
@@ -25,57 +25,6 @@
       expect(project_tree_saver.save).to be true
     end
 
-    context ':export_fast_serialize feature flag checks' do
-      before do
-        expect(Gitlab::ImportExport::Reader).to receive(:new).with(shared: shared).and_return(reader)
-        expect(reader).to receive(:project_tree).and_return(project_tree)
-      end
-
-      let(:serializer) { instance_double('Gitlab::ImportExport::FastHashSerializer') }
-      let(:reader) { instance_double('Gitlab::ImportExport::Reader') }
-      let(:project_tree) do
-        {
-          include: [{ issues: { include: [] } }],
-          preload: { issues: nil }
-        }
-      end
-
-      context 'when :export_fast_serialize feature is enabled' do
-        before do
-          stub_feature_flags(export_fast_serialize: true)
-        end
-
-        it 'uses FastHashSerializer' do
-          expect(Gitlab::ImportExport::FastHashSerializer)
-            .to receive(:new)
-            .with(project, project_tree)
-            .and_return(serializer)
-
-          expect(serializer).to receive(:execute)
-
-          project_tree_saver.save
-        end
-      end
-
-      context 'when :export_fast_serialize feature is disabled' do
-        before do
-          stub_feature_flags(export_fast_serialize: false)
-        end
-
-        it 'is serialized via built-in `as_json`' do
-          expect(project).to receive(:as_json).with(project_tree)
-
-          project_tree_saver.save
-        end
-      end
-    end
-
-    # It is mostly duplicated in
-    # `spec/lib/gitlab/import_export/fast_hash_serializer_spec.rb`
-    # except:
-    # context 'with description override' do
-    # context 'group members' do
-    # ^ These are specific for the Project::TreeSaver
     context 'JSON' do
       let(:saved_project_json) do
         project_tree_saver.save
@@ -392,6 +341,6 @@ def setup_project
   end
 
   def project_json(filename)
-    JSON.parse(IO.read(filename))
+    ::JSON.parse(IO.read(filename))
   end
 end
diff --git a/spec/models/ci/build_spec.rb b/spec/models/ci/build_spec.rb
index 6c77b16f9085f..a661aa6e3a915 100644
--- a/spec/models/ci/build_spec.rb
+++ b/spec/models/ci/build_spec.rb
@@ -3946,6 +3946,53 @@ def run_job_without_exception
     end
   end
 
+  describe '#collect_coverage_reports!' do
+    subject { build.collect_coverage_reports!(coverage_report) }
+
+    let(:coverage_report) { Gitlab::Ci::Reports::CoverageReports.new }
+
+    it { expect(coverage_report.files).to eq({}) }
+
+    context 'when build has a coverage report' do
+      context 'when there is a Cobertura coverage report from simplecov-cobertura' do
+        before do
+          create(:ci_job_artifact, :cobertura, job: build, project: build.project)
+        end
+
+        it 'parses blobs and add the results to the coverage report' do
+          expect { subject }.not_to raise_error
+
+          expect(coverage_report.files.keys).to match_array(['app/controllers/abuse_reports_controller.rb'])
+          expect(coverage_report.files['app/controllers/abuse_reports_controller.rb'].count).to eq(23)
+        end
+      end
+
+      context 'when there is a Cobertura coverage report from gocov-xml' do
+        before do
+          create(:ci_job_artifact, :coverage_gocov_xml, job: build, project: build.project)
+        end
+
+        it 'parses blobs and add the results to the coverage report' do
+          expect { subject }.not_to raise_error
+
+          expect(coverage_report.files.keys).to match_array(['auth/token.go', 'auth/rpccredentials.go'])
+          expect(coverage_report.files['auth/token.go'].count).to eq(49)
+          expect(coverage_report.files['auth/rpccredentials.go'].count).to eq(10)
+        end
+      end
+
+      context 'when there is a corrupted Cobertura coverage report' do
+        before do
+          create(:ci_job_artifact, :coverage_with_corrupted_data, job: build, project: build.project)
+        end
+
+        it 'raises an error' do
+          expect { subject }.to raise_error(Gitlab::Ci::Parsers::Coverage::Cobertura::CoberturaParserError)
+        end
+      end
+    end
+  end
+
   describe '#report_artifacts' do
     subject { build.report_artifacts }
 
diff --git a/spec/models/ci/job_artifact_spec.rb b/spec/models/ci/job_artifact_spec.rb
index 0a7a44b225c89..de93c3c167514 100644
--- a/spec/models/ci/job_artifact_spec.rb
+++ b/spec/models/ci/job_artifact_spec.rb
@@ -70,6 +70,22 @@
     end
   end
 
+  describe '.coverage_reports' do
+    subject { described_class.coverage_reports }
+
+    context 'when there is a coverage report' do
+      let!(:artifact) { create(:ci_job_artifact, :cobertura) }
+
+      it { is_expected.to eq([artifact]) }
+    end
+
+    context 'when there are no coverage reports' do
+      let!(:artifact) { create(:ci_job_artifact, :archive) }
+
+      it { is_expected.to be_empty }
+    end
+  end
+
   describe '.erasable' do
     subject { described_class.erasable }
 
diff --git a/spec/models/ci/pipeline_spec.rb b/spec/models/ci/pipeline_spec.rb
index 51a2e2aff67d9..f18c77988c829 100644
--- a/spec/models/ci/pipeline_spec.rb
+++ b/spec/models/ci/pipeline_spec.rb
@@ -344,9 +344,9 @@
   end
 
   describe '.with_reports' do
-    subject { described_class.with_reports(Ci::JobArtifact.test_reports) }
-
     context 'when pipeline has a test report' do
+      subject { described_class.with_reports(Ci::JobArtifact.test_reports) }
+
       let!(:pipeline_with_report) { create(:ci_pipeline, :with_test_reports) }
 
       it 'selects the pipeline' do
@@ -354,7 +354,19 @@
       end
     end
 
+    context 'when pipeline has a coverage report' do
+      subject { described_class.with_reports(Ci::JobArtifact.coverage_reports) }
+
+      let!(:pipeline_with_report) { create(:ci_pipeline, :with_coverage_reports) }
+
+      it 'selects the pipeline' do
+        is_expected.to eq([pipeline_with_report])
+      end
+    end
+
     context 'when pipeline does not have metrics reports' do
+      subject { described_class.with_reports(Ci::JobArtifact.test_reports) }
+
       let!(:pipeline_without_report) { create(:ci_empty_pipeline) }
 
       it 'does not select the pipeline' do
@@ -2730,6 +2742,43 @@ def create_build(name, stage_idx)
     end
   end
 
+  describe '#coverage_reports' do
+    subject { pipeline.coverage_reports }
+
+    context 'when pipeline has multiple builds with coverage reports' do
+      let!(:build_rspec) { create(:ci_build, :success, name: 'rspec', pipeline: pipeline, project: project) }
+      let!(:build_golang) { create(:ci_build, :success, name: 'golang', pipeline: pipeline, project: project) }
+
+      before do
+        create(:ci_job_artifact, :cobertura, job: build_rspec, project: project)
+        create(:ci_job_artifact, :coverage_gocov_xml, job: build_golang, project: project)
+      end
+
+      it 'returns coverage reports with collected data' do
+        expect(subject.files.keys).to match_array([
+          "auth/token.go",
+          "auth/rpccredentials.go",
+          "app/controllers/abuse_reports_controller.rb"
+        ])
+      end
+
+      context 'when builds are retried' do
+        let!(:build_rspec) { create(:ci_build, :retried, :success, name: 'rspec', pipeline: pipeline, project: project) }
+        let!(:build_golang) { create(:ci_build, :retried, :success, name: 'golang', pipeline: pipeline, project: project) }
+
+        it 'does not take retried builds into account' do
+          expect(subject.files).to eql({})
+        end
+      end
+    end
+
+    context 'when pipeline does not have any builds with coverage reports' do
+      it 'returns empty coverage reports' do
+        expect(subject.files).to eql({})
+      end
+    end
+  end
+
   describe '#total_size' do
     let!(:build_job1) { create(:ci_build, pipeline: pipeline, stage_idx: 0) }
     let!(:build_job2) { create(:ci_build, pipeline: pipeline, stage_idx: 0) }
diff --git a/spec/models/merge_request_spec.rb b/spec/models/merge_request_spec.rb
index 7cadce12213ea..137795dcbc342 100644
--- a/spec/models/merge_request_spec.rb
+++ b/spec/models/merge_request_spec.rb
@@ -908,6 +908,16 @@ def set_compare(merge_request)
     end
   end
 
+  describe '#new_paths' do
+    let(:merge_request) do
+      create(:merge_request, source_branch: 'expand-collapse-files', target_branch: 'master')
+    end
+
+    it 'returns new path of changed files' do
+      expect(merge_request.new_paths.count).to eq(105)
+    end
+  end
+
   describe "#related_notes" do
     let!(:merge_request) { create(:merge_request) }
 
@@ -1581,6 +1591,24 @@ def set_compare(merge_request)
     end
   end
 
+  describe '#has_coverage_reports?' do
+    subject { merge_request.has_coverage_reports? }
+
+    let(:project) { create(:project, :repository) }
+
+    context 'when head pipeline has coverage reports' do
+      let(:merge_request) { create(:merge_request, :with_coverage_reports, source_project: project) }
+
+      it { is_expected.to be_truthy }
+    end
+
+    context 'when head pipeline does not have coverage reports' do
+      let(:merge_request) { create(:merge_request, source_project: project) }
+
+      it { is_expected.to be_falsey }
+    end
+  end
+
   describe '#calculate_reactive_cache' do
     let(:project) { create(:project, :repository) }
     let(:merge_request) { create(:merge_request, source_project: project) }
@@ -1663,6 +1691,60 @@ def set_compare(merge_request)
     end
   end
 
+  describe '#find_coverage_reports' do
+    let(:project) { create(:project, :repository) }
+    let(:merge_request) { create(:merge_request, :with_coverage_reports, source_project: project) }
+    let(:pipeline) { merge_request.head_pipeline }
+
+    subject { merge_request.find_coverage_reports }
+
+    context 'when head pipeline has coverage reports' do
+      let!(:job) do
+        create(:ci_build, options: { artifacts: { reports: { cobertura: ['cobertura-coverage.xml'] } } }, pipeline: pipeline)
+      end
+
+      let!(:artifacts_metadata) { create(:ci_job_artifact, :metadata, job: job) }
+
+      context 'when reactive cache worker is parsing results asynchronously' do
+        it 'returns status' do
+          expect(subject[:status]).to eq(:parsing)
+        end
+      end
+
+      context 'when reactive cache worker is inline' do
+        before do
+          synchronous_reactive_cache(merge_request)
+        end
+
+        it 'returns status and data' do
+          expect(subject[:status]).to eq(:parsed)
+        end
+
+        context 'when an error occurrs' do
+          before do
+            merge_request.update!(head_pipeline: nil)
+          end
+
+          it 'returns an error message' do
+            expect(subject[:status]).to eq(:error)
+          end
+        end
+
+        context 'when cached results is not latest' do
+          before do
+            allow_next_instance_of(Ci::GenerateCoverageReportsService) do |service|
+              allow(service).to receive(:latest?).and_return(false)
+            end
+          end
+
+          it 'raises and InvalidateReactiveCache error' do
+            expect { subject }.to raise_error(ReactiveCaching::InvalidateReactiveCache)
+          end
+        end
+      end
+    end
+  end
+
   describe '#compare_test_reports' do
     subject { merge_request.compare_test_reports }
 
diff --git a/spec/models/user_spec.rb b/spec/models/user_spec.rb
index 6303fe8a5bbc5..849494e7cd4e9 100644
--- a/spec/models/user_spec.rb
+++ b/spec/models/user_spec.rb
@@ -4335,4 +4335,27 @@ def access_levels(groups)
       it { expect(user.user_detail).to be_persisted }
     end
   end
+
+  describe '#gitlab_employee?' do
+    using RSpec::Parameterized::TableSyntax
+
+    subject { user.gitlab_employee? }
+
+    where(:email, :is_com, :expected_result) do
+      'test@gitlab.com'   | true  | true
+      'test@example.com'  | true  | false
+      'test@gitlab.com'   | false | false
+      'test@example.com'  | false | false
+    end
+
+    with_them do
+      let(:user) { build(:user, email: email) }
+
+      before do
+        allow(Gitlab).to receive(:com?).and_return(is_com)
+      end
+
+      it { is_expected.to be expected_result }
+    end
+  end
 end
diff --git a/spec/presenters/projects/import_export/project_export_presenter_spec.rb b/spec/presenters/projects/import_export/project_export_presenter_spec.rb
new file mode 100644
index 0000000000000..052ca36974a97
--- /dev/null
+++ b/spec/presenters/projects/import_export/project_export_presenter_spec.rb
@@ -0,0 +1,92 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Projects::ImportExport::ProjectExportPresenter do
+  let_it_be(:group) { create(:group) }
+  let_it_be(:project) { create(:project, group: group) }
+  let_it_be(:user) { create(:user) }
+
+  subject { described_class.new(project, current_user: user) }
+
+  describe '#description' do
+    context "override_description not provided" do
+      it "keeps original description" do
+        expect(subject.description).to eq(project.description)
+      end
+    end
+
+    context "override_description provided" do
+      let(:description) { "overridden description" }
+
+      subject { described_class.new(project, current_user: user, override_description: description) }
+
+      it "overrides description" do
+        expect(subject.description).to eq(description)
+      end
+    end
+  end
+
+  describe '#as_json' do
+    context "override_description not provided" do
+      it "keeps original description" do
+        expect(subject.as_json["description"]).to eq(project.description)
+      end
+    end
+
+    context "override_description provided" do
+      let(:description) { "overridden description" }
+
+      subject { described_class.new(project, current_user: user, override_description: description) }
+
+      it "overrides description" do
+        expect(subject.as_json["description"]).to eq(description)
+      end
+    end
+  end
+
+  describe '#project_members' do
+    let(:user2) { create(:user, email: 'group@member.com') }
+    let(:member_emails) do
+      subject.project_members.map do |pm|
+        pm.user.email
+      end
+    end
+
+    before do
+      group.add_developer(user2)
+    end
+
+    it 'does not export group members if it has no permission' do
+      group.add_developer(user)
+
+      expect(member_emails).not_to include('group@member.com')
+    end
+
+    it 'does not export group members as maintainer' do
+      group.add_maintainer(user)
+
+      expect(member_emails).not_to include('group@member.com')
+    end
+
+    it 'exports group members as group owner' do
+      group.add_owner(user)
+
+      expect(member_emails).to include('group@member.com')
+    end
+
+    context 'as admin' do
+      let(:user) { create(:admin) }
+
+      it 'exports group members as admin' do
+        expect(member_emails).to include('group@member.com')
+      end
+
+      it 'exports group members as project members' do
+        member_types = subject.project_members.map { |pm| pm.source_type }
+
+        expect(member_types).to all(eq('Project'))
+      end
+    end
+  end
+end
diff --git a/spec/services/ci/retry_build_service_spec.rb b/spec/services/ci/retry_build_service_spec.rb
index 6cecab8656a77..0ed4dcec93e2f 100644
--- a/spec/services/ci/retry_build_service_spec.rb
+++ b/spec/services/ci/retry_build_service_spec.rb
@@ -36,7 +36,8 @@
        job_artifacts_performance job_artifacts_lsif
        job_artifacts_codequality job_artifacts_metrics scheduled_at
        job_variables waiting_for_resource_at job_artifacts_metrics_referee
-       job_artifacts_network_referee job_artifacts_dotenv needs].freeze
+       job_artifacts_network_referee job_artifacts_dotenv
+       job_artifacts_cobertura needs].freeze
 
   IGNORE_ACCESSORS =
     %i[type lock_version target_url base_tags trace_sections
diff --git a/spec/services/projects/import_export/export_service_spec.rb b/spec/services/projects/import_export/export_service_spec.rb
index e00507d1827a3..1315ae2632237 100644
--- a/spec/services/projects/import_export/export_service_spec.rb
+++ b/spec/services/projects/import_export/export_service_spec.rb
@@ -26,10 +26,28 @@
       service.execute
     end
 
-    it 'saves the models' do
-      expect(Gitlab::ImportExport::Project::TreeSaver).to receive(:new).and_call_original
+    context 'when :streaming_serializer feature is enabled' do
+      before do
+        stub_feature_flags(streaming_serializer: true)
+      end
 
-      service.execute
+      it 'saves the models' do
+        expect(Gitlab::ImportExport::Project::TreeSaver).to receive(:new).and_call_original
+
+        service.execute
+      end
+    end
+
+    context 'when :streaming_serializer feature is disabled' do
+      before do
+        stub_feature_flags(streaming_serializer: false)
+      end
+
+      it 'saves the models' do
+        expect(Gitlab::ImportExport::Project::LegacyTreeSaver).to receive(:new).and_call_original
+
+        service.execute
+      end
     end
 
     it 'saves the uploads' do
diff --git a/spec/support/shared_examples/requests/api/discussions_shared_examples.rb b/spec/support/shared_examples/requests/api/discussions_shared_examples.rb
index 939ea40572420..3ad2263688b55 100644
--- a/spec/support/shared_examples/requests/api/discussions_shared_examples.rb
+++ b/spec/support/shared_examples/requests/api/discussions_shared_examples.rb
@@ -55,6 +55,58 @@
 end
 
 RSpec.shared_examples 'discussions API' do |parent_type, noteable_type, id_name, can_reply_to_individual_notes: false|
+  shared_examples 'is_gitlab_employee attribute presence' do
+    subject { get api("/#{parent_type}/#{parent.id}/#{noteable_type}/#{noteable[id_name]}/discussions", user) }
+
+    before do
+      allow(Gitlab).to receive(:com?).and_return(true)
+      user.update(email: email)
+      user.confirm
+    end
+
+    context 'when author is a gitlab employee' do
+      let(:email) { 'test@gitlab.com' }
+
+      it 'returns is_gitlab_employee as true' do
+        subject
+
+        expect(json_response.first["notes"].first["author"]['is_gitlab_employee']).to be true
+      end
+    end
+
+    shared_examples 'non inclusion of gitlab employee badge' do
+      it 'does not include is_gitlab_employee attribute' do
+        subject
+
+        expect(json_response.first["notes"].first["author"]).not_to have_key('is_gitlab_employee')
+      end
+    end
+
+    context 'when author is not a gitlab employee' do
+      let(:email) { 'test@example.com' }
+
+      it_behaves_like 'non inclusion of gitlab employee badge'
+    end
+
+    describe 'when feature flag is disabled' do
+      before do
+        stub_feature_flags(gitlab_employee_badge: false)
+      end
+
+      context 'when author is a gitlab employee' do
+        let(:email) { 'test@gitlab.com' }
+
+        it_behaves_like 'non inclusion of gitlab employee badge'
+      end
+
+      context 'when author is not a gitlab employee' do
+        let(:email) { 'test@example.com' }
+
+        it_behaves_like 'non inclusion of gitlab employee badge'
+      end
+    end
+  end
+
   describe "GET /#{parent_type}/:id/#{noteable_type}/:noteable_id/discussions" do
     it "returns an array of discussions" do
       get api("/#{parent_type}/#{parent.id}/#{noteable_type}/#{noteable[id_name]}/discussions", user)
@@ -78,6 +130,8 @@
 
       expect(response).to have_gitlab_http_status(:not_found)
     end
+
+    it_behaves_like 'is_gitlab_employee attribute presence'
   end
 
   describe "GET /#{parent_type}/:id/#{noteable_type}/:noteable_id/discussions/:discussion_id" do
@@ -196,6 +250,8 @@
         end
       end
     end
+
+    it_behaves_like 'is_gitlab_employee attribute presence'
   end
 
   describe "POST /#{parent_type}/:id/#{noteable_type}/:noteable_id/discussions/:discussion_id/notes" do