Parse change headers with "Version <v>" pattern too. (#8939)

Author: isoos

app/lib/shared/changelog.dart

@@ -382,11 +382,12 @@ class ChangelogParser {
   /// - `unreleased`
   /// - `next release (...)`
   _ParsedHeader? _tryParseAsHeader(html.Element elem, String input) {
+    assert(input == input.trim());
     final level = _acceptedHeaderTags.indexOf(elem.localName!);
 
     final anchor = elem.attributes['id'];
     // special case: unreleased
-    final inputLowerCase = input.toLowerCase().trim();
+    final inputLowerCase = input.toLowerCase();
     final unreleasedTexts = ['unreleased', 'next release'];
     for (final unreleasedText in unreleasedTexts) {
       if (inputLowerCase == unreleasedText) {
@@ -401,6 +402,12 @@ class ChangelogParser {
       }
     }
 
+    // remove leading 'Version' label
+    const versionLabelPrefix = 'version ';
+    if (inputLowerCase.startsWith(versionLabelPrefix)) {
+      input = input.substring(versionLabelPrefix.length).trim();
+    }
+
     // extract version
     final versionPart = input.split(' ').firstWhereOrNull((e) => e.isNotEmpty);
     if (versionPart == null) {

app/test/shared/changelog_test.dart

@@ -118,11 +118,16 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 ### Added
 - Pre-release version
+
+## Version 0.9.0 (Bugfix release)
+
+- Fixing a bug.
+
 ''';
 
       final changelog = _parse(markdown);
 
-      expect(changelog.releases, hasLength(3));
+      expect(changelog.releases, hasLength(4));
 
       expect(changelog.releases[0].version, equals('2.0.0'));
       expect(changelog.releases[0].date, equals(DateTime(2025, 8, 1)));
@@ -132,6 +137,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
       expect(changelog.releases[2].version, equals('1.0.0-beta.1'));
       expect(changelog.releases[2].date, equals(DateTime(2025, 1, 15)));
+
+      expect(changelog.releases[3].version, equals('0.9.0'));
+      expect(changelog.releases[3].note, '(Bugfix release)');
     });
 
     test('handles different date formats', () {
@@ -234,6 +242,21 @@ void main() {
       expect(changelog.releases[1].version, equals('1.0.0'));
     });
 
+    test('handles mixed header levels #2', () {
+      const markdown = '''## Changelog
+
+#### v2.0.0
+
+#### v1.0.0
+
+''';
+      final changelog = _parse(markdown);
+      expect(
+        changelog.releases.map((e) => e.version).toList(),
+        ['2.0.0', '1.0.0'],
+      );
+    });
+
     test('handles embedded header levels', () {
       const markdown = '''
 # Changelog