fix: skip stash when nothing to stash (fix #5)

Author: hyiso

lib/src/git.dart

@@ -49,7 +49,7 @@ Future<String> execGit(
   final result =
       await Process.run('git', gitArgs, workingDirectory: workingDirectory);
   if (result.exitCode != 0) {
-    throw Exception(result.stderr);
+    throw Exception('execGit ${result.stderr}');
   }
   String output = result.stdout as String;
   if (output.endsWith('\n')) {

lib/src/git_workflow.dart

@@ -1,3 +1,4 @@
+import 'dart:io';
 import 'dart:math';
 import 'package:path/path.dart';
 import 'package:verbose/verbose.dart';
@@ -33,7 +34,7 @@ List<String> processRenames(List<String> files,
   });
 }
 
-const kStash = 'lint_staged automatic backup';
+const kStashMessage = 'lint_staged automatic backup';
 
 const kMergeHead = 'MERGE_HEAD';
 const kMergeMode = 'MERGE_MODE';
@@ -107,8 +108,12 @@ class GitWorkflow {
   Future<String> getBackupStash(LintStagedContext ctx) async {
     final stashes =
         await execGit(['stash', 'list'], workingDirectory: workingDirectory);
+
+    if (stashes.isEmpty) {
+      return '';
+    }
     final index =
-        stashes.split('\n').indexWhere((line) => line.contains(kStash));
+        stashes.split('\n').indexWhere((line) => line.contains(kStashMessage));
     if (index == -1) {
       ctx.errors.add(kGetBackupStashError);
       throw Exception('lint_staged automatic backup is missing!');
@@ -255,14 +260,21 @@ class GitWorkflow {
       /// - git stash can't infer RD or MD states correctly, and will lose the deletion
       deletedFiles = await getDeletedFiles();
 
-      // Save stash of all staged files.
-      // The `stash create` command creates a dangling commit without removing any files,
-      // and `stash store` saves it as an actual stash.
-      final hash = await execGit(['stash', 'create'],
-          workingDirectory: workingDirectory);
-      await execGit(['stash', 'store', '--quiet', '--message', kStash, hash],
+      /// Save stash of all staged files.
+      /// The `stash create` command creates a dangling commit without removing any files,
+      /// and `stash store` saves it as an actual stash.
+      final stash = await execGit(['stash', 'create'],
           workingDirectory: workingDirectory);
 
+      /// When there's nothing to stash, just skip.
+      if (stash.isNotEmpty) {
+        await execGit(
+            ['stash', 'store', '--quiet', '--message', kStashMessage, stash],
+            workingDirectory: workingDirectory);
+      } else {
+        verbose('Nothing to stash.');
+      }
+
       verbose('Done backing up original state!');
     } catch (e) {
       handleError(e, ctx);
@@ -326,6 +338,8 @@ class GitWorkflow {
     } catch (applyError) {
       verbose('Error while restoring changes:');
       verbose(applyError.toString());
+      verbose(
+          'Content of file $unstagedPatch is:\n${File(unstagedPatch).readAsStringSync()}');
       verbose('Retrying with 3-way merge');
       try {
         // Retry with a 3-way merge if normal apply fails
@@ -368,6 +382,7 @@ class GitWorkflow {
 
       verbose('Done restoring original state!');
     } catch (error) {
+      verbose('Restoring original state error: $error');
       handleError(error, ctx, kRestoreOriginalStateError);
     }
   }
@@ -378,19 +393,25 @@ class GitWorkflow {
   Future<void> cleanup(LintStagedContext ctx) async {
     try {
       verbose('Dropping backup stash...');
-      await execGit(['stash', 'drop', '--quiet', await getBackupStash(ctx)],
-          workingDirectory: workingDirectory);
+      final stash = await getBackupStash(ctx);
+      if (stash.isNotEmpty) {
+        await execGit([
+          'stash',
+          'drop',
+          '--quiet',
+        ], workingDirectory: workingDirectory);
+      }
       verbose('Done dropping backup stash!');
     } catch (error) {
       handleError(error, ctx);
     }
   }
 
   void handleError(e, LintStagedContext ctx, [Symbol? symbol]) {
+    verbose(StackTrace.current.toString());
     ctx.errors.add(kGitError);
     if (symbol != null) {
       ctx.errors.add(symbol);
     }
-    // throw e;
   }
 }

lib/src/run.dart

@@ -113,9 +113,11 @@ Future<LintStagedContext> runAll({
     await git.hideUnstagedChanges(ctx);
     logger.success('Hiding unstaged changes to partially staged files...');
   }
-  logger.progress('Running tasks for staged files...');
-  await Future.wait(tasks.map((task) => task()));
-  logger.success('Running tasks for staged files...');
+  if (matchedFiles.isNotEmpty) {
+    logger.progress('Running tasks for staged files...');
+    await Future.wait(tasks.map((task) => task()));
+    logger.success('Running tasks for staged files...');
+  }
   if (!applyModifationsSkipped(ctx)) {
     logger.progress('Applying modifications from tasks...');
     await git.applyModifications(ctx);
@@ -126,6 +128,8 @@ Future<LintStagedContext> runAll({
     await git.resotreUnstagedChanges(ctx);
     logger.success('Restoring unstaged changes to partially staged files...');
   }
+  verbose(
+      'should restore origin state: ${restoreOriginalStateEnabled(ctx) && !restoreOriginalStateSkipped(ctx)}');
   if (restoreOriginalStateEnabled(ctx) && !restoreOriginalStateSkipped(ctx)) {
     logger.progress('Reverting to original state because of errors...');
     await git.restoreOriginState(ctx);

test/integration/git_submodules_test.dart

@@ -1,5 +1,3 @@
-import 'dart:io';
-
 import 'package:lint_staged/src/file.dart';
 import 'package:lint_staged/src/git.dart';
 import 'package:path/path.dart' show join;
@@ -16,51 +14,51 @@ void main() {
       print('dir: ${project.dir}');
       await project.setup();
 
+      await project.writeFile('pubspec.yaml', kConfigFormatFix);
+      await project.writeFile('lib/main.dart', kFormattedDart);
+      await project.execGit(['add', '.']);
+      await expectLater(
+          project.gitCommit(gitCommitArgs: ['-m', 'committed pretty file']),
+          completes);
+
       // create a new repo for the git submodule to a temp path
-      String submoduleDir = join(project.dir, 'submodule_temp');
-      if (!await Directory(submoduleDir).exists()) {
-        await Directory(submoduleDir).create(recursive: true);
-      }
-      await execGit(['init', submoduleDir]);
-      await execGit(['config', 'user.name', '"test"'],
-          workingDirectory: submoduleDir);
-      await execGit(['config', 'user.email', '"[email protected]"'],
-          workingDirectory: submoduleDir);
-      await appendFile('README.md', '# Test\n', workingDirectory: submoduleDir);
-      await execGit(['add', 'README.md'], workingDirectory: submoduleDir);
-      await execGit(['commit', '-m initial commit'],
-          workingDirectory: submoduleDir);
+      final submoduleProject = IntegrationProject();
+      await submoduleProject.setup();
 
-      // Add the newly-created repo as a submodule in a new path.
-      // This simulates adding it from a remote. By default file protocol is not allowed,
-      // see https://git-scm.com/docs/git-config#Documentation/git-config.txt-protocolallow
+      /// Add the newly-created repo as a submodule in a new path.
+      /// This simulates adding it from a remote. By default file protocol is not allowed,
+      /// see https://git-scm.com/docs/git-config#Documentation/git-config.txt-protocolallow
       await project.execGit([
         '-c',
         'protocol.file.allow=always',
         'submodule',
         'add',
         '--force',
-        './submodule_temp',
+        submoduleProject.dir,
         './submodule',
       ]);
-      submoduleDir = join(project.dir, 'submodule');
-      // Set these again for Windows git in CI
-      await execGit(['config', 'user.name', '"test"'],
-          workingDirectory: submoduleDir);
-      await execGit(['config', 'user.email', '"[email protected]"'],
-          workingDirectory: submoduleDir);
+
+      /// Commit this submodule
+      await project.execGit(['add', '.']);
+      await expectLater(
+          project.gitCommit(
+              allowEmpty: true, gitCommitArgs: ['-m', 'Add submodule']),
+          completes);
+
+      final submoduleDir = join(project.dir, 'submodule');
       await writeFile('pubspec.yaml', kConfigFormatExit,
           workingDirectory: submoduleDir);
 
-      // Stage pretty file
+      /// Stage pretty file
       await appendFile('lib/main.dart', kFormattedDart,
           workingDirectory: submoduleDir);
-      await execGit(['add', 'lib/main.dart'], workingDirectory: submoduleDir);
+      await execGit(['add', '.'], workingDirectory: submoduleDir);
 
-      // Run lint_staged with `dart format --set-exit-if-changed` and commit formatted file
-      await project.gitCommit(workingDirectory: submoduleDir);
+      /// Run lint_staged with `dart format --set-exit-if-changed` and commit formatted file
+      await expectLater(
+          project.gitCommit(workingDirectory: submoduleDir), completes);
 
-      // Nothing is wrong, so a new commit is created
+      /// Nothing is wrong, so a new commit is created
       expect(
           await execGit(['rev-list', '--count', 'HEAD'],
               workingDirectory: submoduleDir),
@@ -71,6 +69,13 @@ void main() {
           contains('test'));
       expect(await readFile('lib/main.dart', workingDirectory: submoduleDir),
           equals(kFormattedDart));
+
+      /// Commit this submodule
+      await project.execGit(['add', '.']);
+      await expectLater(
+          project.gitCommit(
+              allowEmpty: true, gitCommitArgs: ['-m', 'Update submodule']),
+          completes);
     });
   });
 }

test/integration/utils.dart

@@ -11,6 +11,8 @@ class IntegrationProject {
       : dir = join(Directory.systemTemp.path, 'tmp',
             'husky_test_${DateTime.now().microsecondsSinceEpoch}');
 
+  IntegrationProject.dirctory(this.dir);
+
   Future<void> setup({bool initialCommit = true}) async {
     /// Git init
     await git.execGit(['init', dir]);