fix(cli): support .gitignore ignoring of directories (#6880)

Minor enhancement to support the .gitignore trailing-/ so it only
matches directories.

---

### Changes are visible to end-users: no

### Test plan

- Covered by existing test cases
- New test cases added

GitOrigin-RevId: 2711ceec5d8d5ffe9ec2f045b7c0994d4b0c5d6c

gazelle/common/git/gitignore.go

@@ -15,6 +15,8 @@ import (
 // Must align with patched bazel-gazelle
 const ASPECT_GITIGNORE = "__aspect:gitignore"
 
+type isGitIgnoredFunc = func(string, bool) bool
+
 // Directive to enable/disable gitignore support
 const Directive_GitIgnore = "gitignore"
 
@@ -97,14 +99,14 @@ func parseIgnore(rel string, ignoreReader io.Reader) []gitignore.Pattern {
 	return matcherPatterns
 }
 
-func createMatcherFunc(c *config.Config) func(string) bool {
+func createMatcherFunc(c *config.Config) isGitIgnoredFunc {
 	patterns, patternsFound := c.Exts[ignorePatternsExt]
 	if !patternsFound {
 		return nil
 	}
 
 	matcher := gitignore.NewMatcher(patterns.([]gitignore.Pattern))
-	return func(s string) bool {
-		return matcher.Match(strings.Split(s, "/"), false)
+	return func(s string, isDir bool) bool {
+		return matcher.Match(strings.Split(s, "/"), isDir)
 	}
 }

gazelle/common/git/gitignore_test.go

@@ -12,15 +12,23 @@ func TestGitIgnore(t *testing.T) {
 	shouldMatch := func(what string, c *config.Config, matches ...string) {
 		matcher := createMatcherFunc(c)
 		for _, m := range matches {
-			if !(matcher != nil && matcher(m)) {
+			// Use trailing slash in test data to indicate directory
+			isDir := strings.HasSuffix(m, "/")
+			m = strings.TrimSuffix(m, "/")
+
+			if !(matcher != nil && matcher(m, isDir)) {
 				t.Error(fmt.Sprintf("%s should match '%s'", what, m))
 			}
 		}
 	}
 	shouldNotMatch := func(what string, c *config.Config, matches ...string) {
 		matcher := createMatcherFunc(c)
 		for _, m := range matches {
-			if matcher != nil && matcher(m) {
+			// Use trailing slash in test data to indicate directory
+			isDir := strings.HasSuffix(m, "/")
+			m = strings.TrimSuffix(m, "/")
+
+			if matcher != nil && matcher(m, isDir) {
 				t.Error(fmt.Sprintf("%s should NOT match '%s'", what, m))
 			}
 		}
@@ -183,6 +191,18 @@ func TestGitIgnore(t *testing.T) {
 		shouldMatch("double wildcard", c, "subdir/x.starstar.ts", "subdir/a/b/c/x.starstar.ts", "subdir/a/.starstar.ts")
 		shouldNotMatch("double wildcard different subdir", c, "startstar.ts", ".startstar.ts", "a/starstar.ts")
 	})
+
+	t.Run("dir specific matches", func(t *testing.T) {
+		c := config.New()
+		addIgnoreFileContent(c, "", `
+		    **/node_modules/
+		    **/foo.js/
+		`)
+
+		shouldMatch("dir pattern", c, "node_modules/", "a/b/node_modules/")
+		shouldMatch("dir pattern that looks like a file", c, "foo.js/", "a/b/foo.js/")
+		shouldNotMatch("ending file that looks like dir", c, "node_modules", "x/node_modules", "foo.js", "x/foo.js")
+	})
 }
 
 // Util method to invoke GitIgnore.AddIgnore() with the trimmed string

gazelle/js/tests/ignore_config_files/.test-gitignore

@@ -16,3 +16,6 @@ subtarget/generated.ts
 
 # A global glob configured from the root with no slash
 **-wild.ts
+
+# An ignore pattern exclusively matching directories
+**/modules.ts/

gazelle/js/tests/ignore_config_files/BUILD.out

@@ -24,6 +24,7 @@ ts_project(
         "subdir/nested/index.ts",
         "subdir/not.nested-ig.ts",
         "subdir2/direct-ig.ts",
+        "subdir2/modules.ts",
         "subdir2/not.nested-ig.ts",
     ],
     deps = [

gazelle/js/tests/ignore_config_files/modules.ts/a.ts

@@ -0,0 +1 @@
+import 'bad-import-but-this-dir-is-ignored';

gazelle/js/tests/ignore_config_files/subdir/modules.ts/a.ts

@@ -0,0 +1 @@
+import 'bad-import-but-this-dir-is-ignored';

gazelle/js/tests/ignore_config_files/subdir/nested/modules.ts/a.ts

@@ -0,0 +1 @@
+import 'bad-import-but-this-dir-is-ignored';

patches/bazelbuild_bazel-gazelle_aspect-gitignore.patch

@@ -10,30 +10,45 @@ index 23b1083..1841650 100644
 
  func New() *Config {
  	return &Config{
+diff --git a/walk/config.go b/walk/config.go
+index 1292146..07cdb3d 100644
+--- a/walk/config.go
++++ b/walk/config.go
+@@ -109,6 +109,7 @@ func (cr *Configurer) Configure(c *config.Config, rel string, f *rule.File) {
+ }
+
+ type isIgnoredFunc = func(string) bool
++type isGitIgnoredFunc = func(string, bool) bool
+
+ var nothingIgnored isIgnoredFunc = func(string) bool { return false }
+
 diff --git a/walk/walk.go b/walk/walk.go
-index 7814088..8ebb086 100644
+index 7814088..1ba1b47 100644
 --- a/walk/walk.go
 +++ b/walk/walk.go
-@@ -165,6 +165,13 @@ func visit(c *config.Config, cexts []config.Configurer, knownDirectives map[stri
+@@ -165,6 +165,14 @@ func visit(c *config.Config, cexts []config.Configurer, knownDirectives map[stri
  		return nil, false
  	}
 
 +	// PATCH(gitignore) ---
-+	isGitIgnored, hasGitIgnore := c.Exts[config.ASPECT_GITIGNORE].(isIgnoredFunc)
-+	if !hasGitIgnore || isGitIgnored == nil {
-+		isGitIgnored = nothingIgnored
++	var isGitIgnored isGitIgnoredFunc
++	isGitIgnoredExt, hasGitIgnore := c.Exts[config.ASPECT_GITIGNORE]
++	if hasGitIgnore && isGitIgnoredExt != nil {
++		isGitIgnored = isGitIgnoredExt.(isGitIgnoredFunc)
 +	}
 +	// END PATCH(gitignore) ---
 +
  	var dirs, subdirs, regularFiles []string
  	for _, ent := range ents {
  		base := ent.Name()
-@@ -172,6 +179,11 @@ func visit(c *config.Config, cexts []config.Configurer, knownDirectives map[stri
+@@ -172,6 +180,13 @@ func visit(c *config.Config, cexts []config.Configurer, knownDirectives map[stri
  		if wc.isExcluded(entRel) {
  			continue
  		}
 +		// PATCH(gitignore) ---
-+		if isGitIgnored(entRel) {
++		// NOTE: .gitignore must be applied *before* symlinks are followed
++		// See notes on symlink examples at https://git-scm.com/docs/gitignore#_examples
++		if isGitIgnored != nil && isGitIgnored(entRel, ent.IsDir()) {
 +			continue
 +		}
 +		// END PATCH(gitignore) ---