add test coverage for bad embed comments

crhntr · Aug 18, 2024 · ec1c1b2 · ec1c1b2
1 parent d53fe3b
commit ec1c1b2
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Showing 4 changed files with 34 additions and 5 deletions.
diff --git a/internal/source/template.go b/internal/source/template.go
@@ -170,12 +170,12 @@ func embedFSFilepaths(dir string, fileSet *token.FileSet, files []*ast.File, exp
 				continue
 			}
 			var comment strings.Builder
-			readComments(&comment, decl.Doc, spec.Doc)
+			commentNode := readComments(&comment, decl.Doc, spec.Doc)
 			patterns, err := parsePatterns(comment.String())
 			if err != nil {
 				return nil, err
 			}
-			absMat, err := embeddedFilesMatchingPatternList(patterns, embeddedFiles)
+			absMat, err := embeddedFilesMatchingPatternList(dir, fileSet, commentNode, patterns, embeddedFiles)
 			if err != nil {
 				return nil, err
 			}
@@ -185,7 +185,7 @@ func embedFSFilepaths(dir string, fileSet *token.FileSet, files []*ast.File, exp
 	return nil, fmt.Errorf("variable %s not found", fsIdent.Name)
 }
 
-func embeddedFilesMatchingPatternList(patterns, embeddedFiles []string) ([]string, error) {
+func embeddedFilesMatchingPatternList(dir string, set *token.FileSet, comment ast.Node, patterns, embeddedFiles []string) ([]string, error) {
 	var matches []string
 	for _, fp := range embeddedFiles {
 		for _, pattern := range patterns {
@@ -198,7 +198,7 @@ func embeddedFilesMatchingPatternList(patterns, embeddedFiles []string) ([]strin
 				}
 			}
 			if matched, err := filepath.Match(pat, fp); err != nil {
-				return nil, err
+				return nil, contextError(dir, set, comment.Pos(), fmt.Errorf("embed comment malformed: %w", err))
 			} else if matched {
 				matches = append(matches, fp)
 			}
@@ -209,7 +209,7 @@ func embeddedFilesMatchingPatternList(patterns, embeddedFiles []string) ([]strin
 
 const goEmbedCommentPrefix = "//go:embed"
 
-func readComments(s *strings.Builder, groups ...*ast.CommentGroup) {
+func readComments(s *strings.Builder, groups ...*ast.CommentGroup) ast.Node {
 	for _, c := range groups {
 		if c == nil {
 			continue
@@ -221,7 +221,9 @@ func readComments(s *strings.Builder, groups ...*ast.CommentGroup) {
 			s.WriteString(strings.TrimSpace(strings.TrimPrefix(line.Text, goEmbedCommentPrefix)))
 			s.WriteByte(' ')
 		}
+		return c
 	}
+	return nil
 }
 
 func parsePatterns(input string) ([]string, error) {

diff --git a/internal/source/template_test.go b/internal/source/template_test.go
@@ -309,6 +309,14 @@ func TestTemplates(t *testing.T) {
 		assert.Nil(t, tsGoHTML.Lookup("script.html"))
 		assert.Nil(t, tsGoHTML.Lookup("console_log"))
 	})
+	t.Run("call bad embed pattern", func(t *testing.T) {
+		dir := createTestDir(t, filepath.FromSlash("testdata/bad_embed_pattern.txtar"))
+		goFiles, fileSet := parseGo(t, dir)
+		_, err := source.Templates(dir, "templates", fileSet, goFiles, []string{
+			filepath.Join(dir, "greeting.gohtml"), // null must not be in a path
+		})
+		require.ErrorContains(t, err, `template.go:9:2: embed comment malformed: syntax error in pattern`)
+	})
 }
 
 func createTestDir(t *testing.T, filename string) string {

diff --git a/internal/source/testdata/bad_embed_pattern.txtar b/internal/source/testdata/bad_embed_pattern.txtar
@@ -0,0 +1,17 @@
+-- template.go --
+package main
+
+import (
+	"embed"
+	"html/template"
+)
+
+var (
+	//go:embed "[fail"
+	assetsFS embed.FS
+
+	templates = template.Must(template.ParseFS(assetsFS, "*"))
+)
+
+-- greeting.gohtml --
+Hello, friend!
diff --git a/internal/source/testdata/template_ParseFS.txtar b/internal/source/testdata/template_ParseFS.txtar
@@ -12,6 +12,8 @@ var (
 
 	templates = template.Must(template.ParseFS(templateSource, "*"))
 
+	// allHTML used by templatesHTML and templatesGoHTML to test pattern filtering
+	// this comment ensures the comment parser skips lines not preceded by go:embed
 	//go:embed *html
 	allHTML embed.FS