Add native -exclude and -respect_bazelignore to buildifier

buildifier/README.md

@@ -32,6 +32,20 @@ in a directory recursively:
 buildifier -r path/to/dir
 ```
 
+Paths can be excluded from recursive discovery with repeatable `-exclude`
+patterns. Patterns use the syntax of Bazel's `glob()`: `*` and `?` match within a
+single path segment and `**` matches any number of segments. They are relative to
+the workspace root, wherever buildifier runs, and use forward slashes on every
+platform. A pattern matching a directory excludes everything below it:
+
+```bash
+buildifier -r -exclude='third_party/**/vendor' -exclude='**/node_modules' .
+```
+
+By default, the paths listed in the workspace's `.bazelignore` and the patterns
+passed to `ignore_directories()` in its `REPO.bazel` are excluded too. Use
+`-respect_bazelignore=false` to discover them anyway.
+
 Buildifier supports the following file types: `BUILD`, `WORKSPACE`, `.bzl`, and
 default, the latter is reserved for Starlark files buildifier doesn't know about
 (e.g. configuration files for third-party projects that use Starlark). The

buildifier/buildifier.go

@@ -191,8 +191,12 @@ func (b *buildifier) run(args []string) int {
 	} else {
 		files := args
 		if b.config.Recursive {
-			var err error
-			files, err = utils.ExpandDirectories(&args)
+			excluder, err := utils.NewExcluder(b.config.Exclude, b.config.RespectBazelignore)
+			if err != nil {
+				fmt.Fprintf(os.Stderr, "buildifier: %v\n", err)
+				return 3
+			}
+			files, err = utils.ExpandDirectories(&args, excluder)
 			if err != nil {
 				fmt.Fprintf(os.Stderr, "buildifier: %v\n", err)
 				return 3

buildifier/config/config.go

@@ -37,7 +37,8 @@ const buildifierJSONFilename = ".buildifier.json"
 // New constructs a Config with default values.
 func New() *Config {
 	return &Config{
-		InputType: "auto",
+		InputType:          "auto",
+		RespectBazelignore: true,
 	}
 }
 
@@ -111,6 +112,13 @@ type Config struct {
 	WarningsList []string `json:"warningsList,omitempty"`
 	// Recursive instructs buildifier to find starlark files recursively
 	Recursive bool `json:"recursive,omitempty"`
+	// Exclude contains glob() patterns, relative to the workspace root, to skip
+	// during recursive file discovery
+	Exclude ArrayFlags `json:"exclude,omitempty"`
+	// RespectBazelignore also skips the paths ignored by the workspace's
+	// .bazelignore and the ignore_directories() of its REPO.bazel during
+	// recursive file discovery
+	RespectBazelignore bool `json:"respectBazelignore"`
 	// Verbose instructs buildifier to output verbose diagnostics
 	Verbose bool `json:"verbose,omitempty"`
 	// DiffCommand is the command to run when the formatting mode is diff
@@ -177,6 +185,8 @@ func (c *Config) FlagSet(name string, errorHandling flag.ErrorHandling) *flag.Fl
 	flags.BoolVar(&c.Verbose, "v", c.Verbose, "print verbose information to standard error")
 	flags.BoolVar(&c.DiffMode, "d", c.DiffMode, "alias for -mode=diff")
 	flags.BoolVar(&c.Recursive, "r", c.Recursive, "find starlark files recursively")
+	flags.Var(&c.Exclude, "exclude", "glob() pattern, relative to the workspace root, to exclude when finding starlark files recursively")
+	flags.BoolVar(&c.RespectBazelignore, "respect_bazelignore", c.RespectBazelignore, "also exclude the paths ignored by .bazelignore and the ignore_directories() of REPO.bazel when finding starlark files recursively")
 	flags.BoolVar(&c.MultiDiff, "multi_diff", c.MultiDiff, "the command specified by the -diff_command flag can diff multiple files in the style of tkdiff (default false)")
 	flags.StringVar(&c.Mode, "mode", c.Mode, "formatting mode: check, diff, or fix (default fix)")
 	flags.StringVar(&c.Format, "format", c.Format, "diagnostics format: text, json or sarif (default text)")

buildifier/config/config_test.go

@@ -30,7 +30,8 @@ func ExampleNew() {
 	fmt.Print(c.String())
 	// Output:
 	// {
-	//   "type": "auto"
+	//   "type": "auto",
+	//   "respectBazelignore": true
 	// }
 }
 
@@ -142,7 +143,8 @@ func ExampleExample() {
 	//     "unreachable",
 	//     "unsorted-dict-items",
 	//     "unused-variable"
-	//   ]
+	//   ],
+	//   "respectBazelignore": true
 	// }
 }
 
@@ -160,13 +162,15 @@ func ExampleFlagSet() {
 	// d: alias for -mode=diff ("false")
 	// diff_command: command to run when the formatting mode is diff (default uses the BUILDIFIER_DIFF, BUILDIFIER_MULTIDIFF, and DISPLAY environment variables to create the diff command) ("")
 	// disable_symlink_safety: per default Buildifier will not write to symlinks pointing outside of the Bazel workspace. Setting this to true will disable this behavior ("false")
+	// exclude: glob() pattern, relative to the workspace root, to exclude when finding starlark files recursively ("")
 	// format: diagnostics format: text, json or sarif (default text) ("")
 	// help: print usage information ("false")
 	// lint: lint mode: off, warn, or fix (default off) ("")
 	// mode: formatting mode: check, diff, or fix (default fix) ("")
 	// multi_diff: the command specified by the -diff_command flag can diff multiple files in the style of tkdiff (default false) ("false")
 	// path: assume BUILD file has this path relative to the workspace directory ("")
 	// r: find starlark files recursively ("false")
+	// respect_bazelignore: also exclude the paths ignored by .bazelignore and the ignore_directories() of REPO.bazel when finding starlark files recursively ("true")
 	// tables: path to JSON file with custom table definitions which will replace the built-in tables ("")
 	// type: Input file type: build (for BUILD files), bzl (for .bzl files), workspace (for WORKSPACE files), module (for MODULE.bazel files), repo (for REPO.bazel files), vendor (for VENDOR.bazel files), default (for generic Starlark files) or auto (default, based on the filename) ("auto")
 	// v: print verbose information to standard error ("false")
@@ -186,6 +190,8 @@ func ExampleFlagSet_parse() {
 		"-d",
 		"--diff_command=diff",
 		"--disable_symlink_safety=true",
+		"--exclude=vendor/*",
+		"--exclude=third_party/*",
 		"--format=json",
 		"--help",
 		"--lint=fix",
@@ -215,6 +221,11 @@ func ExampleFlagSet_parse() {
 	//   "lint": "fix",
 	//   "warnings": "+print,-no-effect",
 	//   "recursive": true,
+	//   "exclude": [
+	//     "vendor/*",
+	//     "third_party/*"
+	//   ],
+	//   "respectBazelignore": true,
 	//   "verbose": true,
 	//   "diffCommand": "diff",
 	//   "multiDiff": true,

buildifier/integration_test.sh

@@ -47,6 +47,8 @@ echo -e '{ "type": "build" }' > test_dir/.buildifier.test.json # demonstrate con
 mkdir test_dir/workspace  # name of a starlark file, but a directory
 mkdir test_dir/.git  # contents should be ignored
 echo -e "a+b" > test_dir/.git/git.bzl
+mkdir -p test_dir/excluded/nested
+echo -e "$INPUT" > test_dir/excluded/nested/excluded.bzl
 cat > test_dir/MODULE.bazel <<'EOF'
 module(name='my-module',version='1.0',compatibility_level=1)
 include("cpp.MODULE.bazel")
@@ -134,9 +136,10 @@ EOF
 cp test_dir/foo.bar golden/foo.bar
 cp test_dir/subdir/build golden/build
 cp test_dir/.git/git.bzl golden/git.bzl
+cp test_dir/excluded/nested/excluded.bzl golden/excluded.bzl
 
 "$buildifier" < test_dir/BUILD > stdout
-"$buildifier" -r test_dir
+"$buildifier" -r --exclude='test_dir/excluded/*' test_dir
 "$buildifier" test.bzl
 "$buildifier" --path=foo.bzl test2.bzl
 "$buildifier" --config=test_dir/.buildifier.test.json < test_dir/test.bzl > test_dir/test.bzl.BUILD.out
@@ -376,7 +379,8 @@ cat > golden/.buildifier.example.json <<EOF
     "unreachable",
     "unsorted-dict-items",
     "unused-variable"
-  ]
+  ],
+  "respectBazelignore": true
 }
 EOF
 
@@ -390,6 +394,7 @@ diff -u test.bzl golden/test.bzl.golden
 diff -u test2.bzl golden/test.bzl.golden
 diff -u stdout golden/test.bzl.golden
 diff -u test_dir/.git/git.bzl golden/git.bzl
+diff -u test_dir/excluded/nested/excluded.bzl golden/excluded.bzl
 diff -u test_dir/MODULE.bazel golden/MODULE.bazel.golden
 diff -u test_dir/REPO.bazel golden/REPO.bazel.golden
 diff -u test_dir/VENDOR.bazel golden/VENDOR.bazel.golden

buildifier/utils/BUILD.bazel

@@ -4,6 +4,7 @@ go_library(
     name = "utils",
     srcs = [
         "diagnostics.go",
+        "exclude.go",
         "sarif.go",
         "tempfile.go",
         "utils.go",
@@ -13,12 +14,14 @@ go_library(
     deps = [
         "//build",
         "//warn",
+        "//wspace",
     ],
 )
 
 go_test(
     name = "utils_test",
     srcs = [
+        "exclude_test.go",
         "sarif_test.go",
         "utils_test.go",
     ],