feat: link to referenced issues/PRs in changelog

packages/melos/lib/src/common/changelog.dart

@@ -23,6 +23,7 @@ import 'package:pub_semver/pub_semver.dart';
 
 import '../package.dart';
 import 'git_commit.dart';
+import 'git_repository.dart';
 import 'pending_package_update.dart';
 
 class Changelog {
@@ -142,6 +143,13 @@ extension ChangelogStringBufferExtension on StringBuffer {
   }
 
   void writePackageUpdateChanges(MelosPendingPackageUpdate update) {
+    final config = update.workspace.config;
+    final repository = config.repository;
+    final linkToCommits = config.commands.version.linkToCommits ?? false;
+
+    String processCommitHeader(String header) =>
+        repository != null ? header.withIssueLinks(repository) : header;
+
     // User provided changelog entry message.
     if (update.userChangelogMessage != null) {
       writeln(' - ${update.userChangelogMessage}');
@@ -162,17 +170,16 @@ extension ChangelogStringBufferExtension on StringBuffer {
         }
 
         if (parsedMessage.isMergeCommit) {
-          writePunctuated(parsedMessage.header);
+          writePunctuated(processCommitHeader(parsedMessage.header));
         } else {
           writeBold(parsedMessage.type!.toUpperCase());
           write(': ');
-          writePunctuated(parsedMessage.description!);
+          writePunctuated(processCommitHeader(parsedMessage.description!));
         }
 
-        if (update.workspace.config.commands.version.linkToCommits ?? false) {
+        if (linkToCommits) {
           final shortCommitId = commit.id.substring(0, 8);
-          final commitUrl =
-              update.workspace.config.repository!.commitUrl(commit.id);
+          final commitUrl = repository!.commitUrl(commit.id);
           write(' (');
           writeLink(shortCommitId, uri: commitUrl.toString());
           write(')');
@@ -207,3 +214,15 @@ List<RichGitCommit> _filteredAndSortedCommits(
 
   return commits;
 }
+
+// https://regex101.com/r/Q1IV9n/1
+final _issueLinkRegexp = RegExp(r'#(\d+)');
+
+extension on String {
+  String withIssueLinks(HostedGitRepository repository) {
+    return replaceAllMapped(_issueLinkRegexp, (match) {
+      final issueUrl = repository.issueUrl(match.group(1)!);
+      return '[${match.group(0)}]($issueUrl)';
+    });
+  }
+}

packages/melos/lib/src/common/git_repository.dart

@@ -27,6 +27,9 @@ abstract class HostedGitRepository {
 
   /// The URL of the commit with the given [id] on the host's web site.
   Uri commitUrl(String id);
+
+  /// The URL of the issue/PR with the given [id] on the host's web site.
+  Uri issueUrl(String id);
 }
 
 /// A git repository, hosted by GitHub.
@@ -62,6 +65,9 @@ class GitHubRepository extends HostedGitRepository {
   @override
   Uri commitUrl(String id) => url.resolve('commit/$id');
 
+  @override
+  Uri issueUrl(String id) => url.resolve('issues/$id');
+
   @override
   String toString() {
     return '''
@@ -116,6 +122,9 @@ class GitLabRepository extends HostedGitRepository {
   @override
   Uri commitUrl(String id) => url.resolve('-/commit/$id');
 
+  @override
+  Uri issueUrl(String id) => url.resolve('-/issues/$id');
+
   @override
   String toString() {
     return '''

packages/melos/test/changelog_test.dart

@@ -15,6 +15,7 @@
  *
  */
 
+import 'package:melos/melos.dart';
 import 'package:melos/src/common/changelog.dart';
 import 'package:melos/src/common/git_commit.dart';
 import 'package:melos/src/common/pending_package_update.dart';
@@ -25,42 +26,68 @@ import 'utils.dart';
 void main() {
   group('linkToCommits', () {
     test('when enabled, adds link to commit behind each one', () {
-      final workspaceBuilder = VirtualWorkspaceBuilder(
-        '''
-        repository: https://github.com/a/b
-        command:
-          version:
-            linkToCommits: true      
-        ''',
-      )..addPackage(
-          '''
-          name: a
-          ''',
-        );
-      final workspace = workspaceBuilder.build();
-      final package = workspace.allPackages['a']!;
-      final commit = RichGitCommit.tryParse(
-        GitCommit(
-          author: 'a',
-          id: 'b2841394a48cd7d84a4966a788842690e543b2ef',
-          date: DateTime.now(),
-          message: 'feat(a): b',
-        ),
-      )!;
-      final update = MelosPendingPackageUpdate(
-        workspace,
-        package,
-        [commit],
-        PackageUpdateReason.commit,
-        logger: workspace.logger,
-      );
-      final changelog = MelosChangelog(update, workspace.logger);
+      final workspace = buildWorkspaceWithRepository();
+      final package = workspace.allPackages['test_pkg']!;
+      final commit = testCommit(message: 'feat(a): b');
       final commitUrl = workspace.config.repository!.commitUrl(commit.id);
 
       expect(
-        changelog.markdown,
+        renderCommitPackageUpdate(workspace, package, commit),
         contains('**FEAT**: b. ([${commit.id.substring(0, 8)}]($commitUrl))'),
       );
     });
   });
+
+  test('when repository is specified, adds links to referenced issues/PRs', () {
+    final workspace = buildWorkspaceWithRepository(linkToCommits: false);
+    final package = workspace.allPackages['test_pkg']!;
+    final commit = testCommit(message: 'feat(a): b (#123)');
+    final issueUrl = workspace.config.repository!.issueUrl('123');
+
+    expect(
+      renderCommitPackageUpdate(workspace, package, commit),
+      contains('**FEAT**: b ([#123]($issueUrl)).'),
+    );
+  });
+}
+
+MelosWorkspace buildWorkspaceWithRepository({bool linkToCommits = true}) {
+  final workspaceBuilder = VirtualWorkspaceBuilder(
+    '''
+    repository: https://github.com/a/b
+    command:
+      version:
+        linkToCommits: $linkToCommits
+    ''',
+  )..addPackage(
+      '''
+      name: test_pkg
+      ''',
+    );
+  return workspaceBuilder.build();
+}
+
+RichGitCommit testCommit({required String message}) => RichGitCommit.tryParse(
+      GitCommit(
+        author: 'a',
+        id: 'b2841394a48cd7d84a4966a788842690e543b2ef',
+        date: DateTime.now(),
+        message: message,
+      ),
+    )!;
+
+String renderCommitPackageUpdate(
+  MelosWorkspace workspace,
+  Package package,
+  RichGitCommit commit,
+) {
+  final update = MelosPendingPackageUpdate(
+    workspace,
+    package,
+    [commit],
+    PackageUpdateReason.commit,
+    logger: workspace.logger,
+  );
+  final changelog = MelosChangelog(update, workspace.logger);
+  return changelog.markdown;
 }

packages/melos/test/git_repository_test.dart

@@ -61,6 +61,16 @@ void main() {
         ),
       );
     });
+
+    test('issueUrl returns correct URL', () {
+      final repo = GitHubRepository(owner: 'a', name: 'b');
+      const issueId = '123';
+
+      expect(
+        repo.issueUrl(issueId),
+        Uri.parse('https://github.com/a/b/issues/123'),
+      );
+    });
   });
 
   group('GitLabRepository', () {
@@ -113,6 +123,16 @@ void main() {
         ),
       );
     });
+
+    test('issueUrl returns correct URL', () {
+      final repo = GitLabRepository(owner: 'a', name: 'b');
+      const issueId = '123';
+
+      expect(
+        repo.issueUrl(issueId),
+        Uri.parse('https://gitlab.com/a/b/-/issues/123'),
+      );
+    });
   });
 
   group('parseHostedGitRepositoryUrl', () {