Implement branch coverage support for exit status modifiers (#934)

Implement branch coverage support for exit status modifiers

CHANGELOG.md

@@ -1,3 +1,9 @@
+Unreleased
+==========
+
+## Enhancements
+* Can now define the minimum_coverage_by_file, maximum_coverage_drop and refuse_coverage_drop by branch as well as line coverage
+
 0.20.0 (2020-11-29)
 ==========
 

README.md

@@ -787,30 +787,36 @@ to help ensure coverage is relatively consistent, rather than being skewed by pa
 
 ```ruby
 SimpleCov.minimum_coverage_by_file 80
+# same as above (the default is to check line coverage by file)
+SimpleCov.minimum_coverage_by_file line: 80
+# check for a minimum line coverage by file of 90% and minimum 80% branch coverage
+SimpleCov.minimum_coverage_by_file line: 90, branch: 80
 ```
 
-(not yet supported for branch coverage)
-
 ### Maximum coverage drop
 
 You can define the maximum coverage drop percentage at once. SimpleCov will return non-zero if exceeded.
 
 ```ruby
 SimpleCov.maximum_coverage_drop 5
+# same as above (the default is to check line drop)
+SimpleCov.maximum_coverage_drop line: 5
+# check for a maximum line drop of 5% and maximum 10% branch drop
+SimpleCov.maximum_coverage_drop line: 5, branch: 10
 ```
 
-(not yet supported for branch coverage)
-
 ### Refuse dropping coverage
 
 You can also entirely refuse dropping coverage between test runs:
 
 ```ruby
 SimpleCov.refuse_coverage_drop
+# same as above (the default is to only refuse line drop)
+SimpleCov.refuse_coverage_drop :line
+# refuse drop for line and branch
+SimpleCov.refuse_coverage_drop :line, :branch
 ```
 
-(not yet supported for branch coverage)
-
 ## Using your own formatter
 
 You can use your own formatter with:

features/maximum_coverage_drop.feature

@@ -7,7 +7,7 @@ Feature:
   Background:
     Given I'm working on the project "faked_project"
 
-  Scenario: maximum_coverage_drop configured cam cause spec failure
+  Scenario: maximum_coverage_drop configured can cause spec failure
     Given SimpleCov for Test/Unit is configured with:
       """
       require 'simplecov'
@@ -34,13 +34,13 @@ Feature:
 
     When I run `bundle exec rake test`
     Then the exit status should not be 0
-    And the output should contain "Coverage has dropped by 3.31% since the last time (maximum allowed: 3.14%)."
+    And the output should contain "Line coverage has dropped by 3.31% since the last time (maximum allowed: 3.14%)."
     And a file named "coverage/.last_run.json" should exist
     And the file "coverage/.last_run.json" should contain:
       """
       {
         "result": {
-          "covered_percent": 88.09
+          "line": 88.09
         }
       }
       """
@@ -61,7 +61,7 @@ Feature:
       """
       {
         "result": {
-          "covered_percent": 88.09
+          "line": 88.09
         }
       }
       """
@@ -84,7 +84,7 @@ Feature:
       """
       {
         "result": {
-          "covered_percent": 84.78
+          "line": 84.78
         }
       }
       """
@@ -110,6 +110,86 @@ Feature:
       end
       """
 
+    And a file named "spec/failing_spec.rb" with:
+      """
+      require "spec_helper"
+      describe FakedProject do
+        it "fails" do
+          expect(false).to eq(true)
+        end
+      end
+      """
+    And the file named "coverage/.last_run.json" with:
+      """
+      {
+        "result": {
+          "line": 100.0
+        }
+      }
+      """
+
+    When I run `bundle exec rspec spec`
+    Then the exit status should be 1
+    And a file named "coverage/.last_run.json" should exist
+    And the file "coverage/.last_run.json" should contain:
+      """
+      {
+        "result": {
+          "line": 100.0
+        }
+      }
+      """
+  Scenario: When the previous last_run file has covered_percent
+    Given SimpleCov for Test/Unit is configured with:
+      """
+      require 'simplecov'
+      SimpleCov.start do
+        add_filter 'test.rb'
+      end
+      """
+    And the file "coverage/.last_run.json" with:
+      """
+      {
+        "result": {
+          "covered_percent": 88.09
+        }
+      }
+      """
+
+    When I run `bundle exec rake test`
+    Then the exit status should be 0
+    And a file named "coverage/.last_run.json" should exist
+    And the file "coverage/.last_run.json" should contain:
+      """
+      {
+        "result": {
+          "line": 88.09
+        }
+      }
+      """
+
+  Scenario: When the previous last_run file has covered_percent does not update resultset
+    Given SimpleCov for RSpec is configured with:
+      """
+      require 'simplecov'
+      SimpleCov.start do
+        add_group 'Libs', 'lib/faked_project/'
+        add_filter '/spec/'
+        maximum_coverage_drop 0
+      end
+      """
+
+    And a file named "lib/faked_project/missed.rb" with:
+      """
+      class UncoveredSourceCode
+        def foo
+          never_reached
+        rescue => err
+          but no one cares about invalid ruby here
+        end
+      end
+      """
+
     And a file named "spec/failing_spec.rb" with:
       """
       require "spec_helper"
@@ -139,3 +219,50 @@ Feature:
         }
       }
       """
+
+  @branch_coverage
+  Scenario: Works together with branch coverage and line coverage, announcing both failures
+    Given SimpleCov for Test/Unit is configured with:
+      """
+      require 'simplecov'
+      SimpleCov.start do
+        add_filter 'test.rb'
+        enable_coverage :branch
+        maximum_coverage_drop line: 0, branch: 0
+      end
+      """
+    And a file named "lib/faked_project/missed.rb" with:
+      """
+      class UncoveredSourceCode
+        def foo
+          never_reached
+        rescue => err
+          but no one cares about invalid ruby here
+        end
+      end
+      """
+
+    And a file named "spec/failing_spec.rb" with:
+      """
+      require "spec_helper"
+      describe FakedProject do
+        it "fails" do
+          false ? true : expect(false).to eq(true)
+        end
+      end
+      """
+    And the file named "coverage/.last_run.json" with:
+      """
+      {
+        "result": {
+          "line": 100.0,
+	  "branch": 100.0
+        }
+      }
+      """
+
+    When I run `bundle exec rake test`
+    Then the exit status should not be 0
+    And the output should contain "Line coverage has dropped by 15.22% since the last time (maximum allowed: 0.00%)."
+    And the output should contain "Branch coverage has dropped by 50.00% since the last time (maximum allowed: 0.00%)."
+    And the output should contain "SimpleCov failed with exit 3"

features/refuse_coverage_drop.feature

@@ -24,7 +24,7 @@ Feature:
       """
       {
         "result": {
-          "covered_percent": 88.09
+          "line": 88.09
         }
       }
       """
@@ -42,13 +42,13 @@ Feature:
 
     When I run `bundle exec rake test`
     Then the exit status should not be 0
-    And the output should contain "Coverage has dropped by 3.31% since the last time (maximum allowed: 0.00%)."
+    And the output should contain "Line coverage has dropped by 3.31% since the last time (maximum allowed: 0.00%)."
     And a file named "coverage/.last_run.json" should exist
     And the file "coverage/.last_run.json" should contain:
       """
       {
         "result": {
-          "covered_percent": 88.09
+          "line": 88.09
         }
       }
       """
@@ -69,7 +69,7 @@ Feature:
       """
       {
         "result": {
-          "covered_percent": 88.09
+          "line": 88.09
         }
       }
       """
@@ -92,7 +92,7 @@ Feature:
       """
       {
         "result": {
-          "covered_percent": 84.78
+          "line": 84.78
         }
       }
       """

lib/simplecov.rb

@@ -285,7 +285,10 @@ def wait_for_other_processes
     # @api private
     #
     def write_last_run(result)
-      SimpleCov::LastRun.write(result: {covered_percent: round_coverage(result.covered_percent)})
+      SimpleCov::LastRun.write(result:
+        result.coverage_statistics.transform_values do |stats|
+          round_coverage(stats.percent)
+        end)
     end
 
     #

lib/simplecov/configuration.rb

@@ -287,20 +287,22 @@ def merge_timeout(seconds = nil)
     #
     # Default is 0% (disabled)
     #
-
-    # rubocop:disable Metrics/CyclomaticComplexity
     def minimum_coverage(coverage = nil)
       return @minimum_coverage ||= {} unless coverage
 
       coverage = {DEFAULT_COVERAGE_CRITERION => coverage} if coverage.is_a?(Numeric)
+
+      raise_on_invalid_coverage(coverage, "minimum_coverage")
+
+      @minimum_coverage = coverage
+    end
+
+    def raise_on_invalid_coverage(coverage, coverage_setting)
       coverage.each_key { |criterion| raise_if_criterion_disabled(criterion) }
       coverage.each_value do |percent|
-        minimum_possible_coverage_exceeded("minimum_coverage") if percent && percent > 100
+        minimum_possible_coverage_exceeded(coverage_setting) if percent && percent > 100
       end
-
-      @minimum_coverage = coverage
     end
-    # rubocop:enable Metrics/CyclomaticComplexity
 
     #
     # Defines the maximum coverage drop at once allowed for the testsuite to pass.
@@ -309,7 +311,13 @@ def minimum_coverage(coverage = nil)
     # Default is 100% (disabled)
     #
     def maximum_coverage_drop(coverage_drop = nil)
-      @maximum_coverage_drop ||= (coverage_drop || 100).to_f.round(2)
+      return @maximum_coverage_drop ||= {} unless coverage_drop
+
+      coverage_drop = {DEFAULT_COVERAGE_CRITERION => coverage_drop} if coverage_drop.is_a?(Numeric)
+
+      raise_on_invalid_coverage(coverage_drop, "maximum_coverage_drop")
+
+      @maximum_coverage_drop = coverage_drop
     end
 
     #
@@ -320,16 +328,23 @@ def maximum_coverage_drop(coverage_drop = nil)
     # Default is 0% (disabled)
     #
     def minimum_coverage_by_file(coverage = nil)
-      minimum_possible_coverage_exceeded("minimum_coverage_by_file") if coverage && coverage > 100
-      @minimum_coverage_by_file ||= (coverage || 0).to_f.round(2)
+      return @minimum_coverage_by_file ||= {} unless coverage
+
+      coverage = {DEFAULT_COVERAGE_CRITERION => coverage} if coverage.is_a?(Numeric)
+
+      raise_on_invalid_coverage(coverage, "minimum_coverage_by_file")
+
+      @minimum_coverage_by_file = coverage
     end
 
     #
     # Refuses any coverage drop. That is, coverage is only allowed to increase.
     # SimpleCov will return non-zero if the coverage decreases.
     #
-    def refuse_coverage_drop
-      maximum_coverage_drop 0
+    def refuse_coverage_drop(*criteria)
+      criteria = coverage_criteria if criteria.empty?
+
+      maximum_coverage_drop(criteria.map { |c| [c, 0] }.to_h)
     end
 
     #