From fafbe464206014c9f9843285d449866c323a70ce Mon Sep 17 00:00:00 2001
From: qvalentin <valentin.theodor@web.de>
Date: Sun, 19 May 2024 15:00:21 +0200
Subject: [PATCH] fix: prevent panic on empty or unsupported template context

fixes https://github.com/mrjosh/helm-ls/issues/81
---
 internal/handler/completion_main_test.go       |  1 +
 internal/handler/hover_main_test.go            | 10 ++++++++++
 internal/language_features/built_in_objects.go |  5 +++--
 internal/language_features/template_context.go |  7 +++++--
 testdata/example/templates/deployment.yaml     | 11 +++++++++++
 5 files changed, 30 insertions(+), 4 deletions(-)

diff --git a/internal/handler/completion_main_test.go b/internal/handler/completion_main_test.go
index 481cbab5..8f49aeec 100644
--- a/internal/handler/completion_main_test.go
+++ b/internal/handler/completion_main_test.go
@@ -176,6 +176,7 @@ func TestCompletionMainSingleLines(t *testing.T) {
 		{`Test completion on {{ range .Values.ingress.hosts }} {{ .^ }} {{ end }}`, []string{"host", "paths"}, []string{}, nil},
 		{`Test completion on {{ range .Values.ingress.hosts }} {{ .ho^  }} {{ end }}`, []string{"host", "paths"}, []string{}, nil},
 		{`Test completion on {{ range .Values.ingress.hosts }} {{ range .paths 	}} {{ .^ }} {{ end }} {{ end }}`, []string{"pathType", "path"}, []string{}, nil},
+		{`Test completion on {{ root := . }} {{ $root.test.^ }}`, []string{}, []string{}, errors.New("[$root test ] is no valid template context for helm")},
 	}
 
 	for _, tt := range testCases {
diff --git a/internal/handler/hover_main_test.go b/internal/handler/hover_main_test.go
index 8eeba435..b31509da 100644
--- a/internal/handler/hover_main_test.go
+++ b/internal/handler/hover_main_test.go
@@ -2,6 +2,7 @@ package handler
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"os"
 	"path/filepath"
@@ -113,6 +114,15 @@ func TestHoverMain(t *testing.T) {
 			expected:      fmt.Sprintf("### %s\n%s\n\n", filepath.Join("..", "..", "testdata", "example", "values.yaml"), "1"),
 			expectedError: nil,
 		},
+		{
+			desc: "Test hover on template context with variables",
+			position: lsp.Position{
+				Line:      74,
+				Character: 50,
+			},
+			expected:      "",
+			expectedError: errors.New("no template context found"),
+		},
 	}
 	for _, tt := range testCases {
 		t.Run(tt.desc, func(t *testing.T) {
diff --git a/internal/language_features/built_in_objects.go b/internal/language_features/built_in_objects.go
index a80ebfca..6f023ba2 100644
--- a/internal/language_features/built_in_objects.go
+++ b/internal/language_features/built_in_objects.go
@@ -42,7 +42,7 @@ func (f *BuiltInObjectsFeature) AppropriateForNode() bool {
 
 func (f *BuiltInObjectsFeature) References() (result []lsp.Location, err error) {
 	templateContext, err := f.getTemplateContext()
-	if err != nil {
+	if err != nil || len(templateContext) == 0 {
 		return []lsp.Location{}, err
 	}
 
@@ -67,7 +67,8 @@ func (f *BuiltInObjectsFeature) getDefinitionLocations(templateContext lsplocal.
 }
 
 func (f *BuiltInObjectsFeature) Hover() (string, error) {
-	templateContext, _ := f.getTemplateContext()
+	templateContext, err := f.getTemplateContext()
+
 	docs, err := f.builtInOjectDocsLookup(templateContext[0], helmdocs.BuiltInObjects)
 	return docs.Doc, err
 }
diff --git a/internal/language_features/template_context.go b/internal/language_features/template_context.go
index 01da658e..cf088edf 100644
--- a/internal/language_features/template_context.go
+++ b/internal/language_features/template_context.go
@@ -35,7 +35,7 @@ func (f *TemplateContextFeature) AppropriateForNode() bool {
 
 func (f *TemplateContextFeature) References() (result []lsp.Location, err error) {
 	templateContext, err := f.getTemplateContext()
-	if err != nil {
+	if err != nil || len(templateContext) == 0 {
 		return []lsp.Location{}, err
 	}
 
@@ -45,7 +45,7 @@ func (f *TemplateContextFeature) References() (result []lsp.Location, err error)
 
 func (f *TemplateContextFeature) Definition() (result []lsp.Location, err error) {
 	templateContext, err := f.getTemplateContext()
-	if err != nil {
+	if err != nil || len(templateContext) == 0 {
 		return []lsp.Location{}, err
 	}
 	return f.getDefinitionLocations(templateContext), nil
@@ -81,6 +81,9 @@ func (f *TemplateContextFeature) getDefinitionLocations(templateContext lsplocal
 
 func (f *TemplateContextFeature) Hover() (string, error) {
 	templateContext, err := f.getTemplateContext()
+	if err != nil || len(templateContext) == 0 {
+		return "", err
+	}
 
 	switch templateContext[0] {
 	case "Values":
diff --git a/testdata/example/templates/deployment.yaml b/testdata/example/templates/deployment.yaml
index 6d2f3764..d77fd2d8 100644
--- a/testdata/example/templates/deployment.yaml
+++ b/testdata/example/templates/deployment.yaml
@@ -70,3 +70,14 @@ spec:
         {{- end }}
       {{- end }}
       hosts: {{ .Values.ingress.hosts }}
+
+      {{- $root := . -}}
+      {{- range $type, $config := $root.Values.deployments }}
+      apiVersion: apps/v1
+      kind: Deployment
+      metadata:
+        name: my-app-{{ $type }}
+      spec:
+        replicas: {{ $config.hpa.minReplicas }}
+      ---
+      {{- end }}