Surface lint release version on lint pages (#7187)

Author: parlough

site/lib/_sass/components/_tags.scss

@@ -64,6 +64,10 @@
     &.red {
       background-color: rgb(255, 205, 200);
     }
+
+    &.grey {
+      background-color: rgb(230, 230, 230);
+    }
   }
 
   span.tag-label {

site/lib/src/components/common/tags.dart

@@ -5,6 +5,7 @@
 import 'package:jaspr/dom.dart';
 import 'package:jaspr/jaspr.dart';
 
+import '../../util.dart';
 import 'material_icon.dart';
 
 /// A display of multiple categorical or descriptive tags.
@@ -28,16 +29,16 @@ class Tag extends StatelessComponent {
     this.icon,
     this.title,
     this.label,
-    this.color,
     this.link,
+    this.color = TagColor.blue,
   });
 
   final String content;
   final String? icon;
   final String? title;
   final String? label;
-  final String? color;
   final String? link;
+  final TagColor color;
 
   @override
   Component build(BuildContext context) {
@@ -49,20 +50,30 @@ class Tag extends StatelessComponent {
       'title': ?title,
       'aria-label': ?(label ?? title),
     };
+    final classes = ['tag-label', color.name].toClasses;
 
     if (link case final link?) {
       return a(
         href: link,
-        classes: 'tag-label',
+        classes: classes,
         attributes: attributes,
         children,
       );
     }
 
     return div(
-      classes: 'tag-label',
+      classes: classes,
       attributes: attributes,
       children,
     );
   }
 }
+
+/// A supported background color for a [Tag].
+enum TagColor {
+  blue,
+  green,
+  orange,
+  red,
+  grey,
+}

site/lib/src/models/lints.dart

@@ -6,6 +6,7 @@ import 'dart:convert';
 import 'dart:io';
 
 import 'package:path/path.dart' as p;
+import 'package:pub_semver/pub_semver.dart' show Version;
 
 import '../util.dart';
 
@@ -48,4 +49,15 @@ extension type LintDetails(Map<String, Object?> details) {
   String get fixStatus => details['fixStatus'] as String;
   String get docs => details['details'] as String;
   String get sinceDartSdk => details['sinceDartSdk'] as String;
+  Version? get releasedInVersion {
+    try {
+      final rawVersion = sinceDartSdk.split('.').length == 2
+          ? '$sinceDartSdk.0'
+          : sinceDartSdk;
+      return Version.parse(rawVersion);
+    } on FormatException {
+      // Assume the lint isn't released if the format isn't understood.
+    }
+    return null;
+  }
 }

site/lib/src/pages/custom_pages.dart

@@ -14,6 +14,7 @@ import '../components/common/tags.dart';
 import '../markdown/markdown_parser.dart';
 import '../models/diagnostic_model.dart';
 import '../models/lints.dart';
+import '../utils/server_only_utils.dart';
 import 'glossary.dart';
 
 /// All pages that should be loaded from memory rather than
@@ -184,43 +185,49 @@ List<MemoryPage> get _lintMemoryPages {
               }
             }
 
+            final releasedInVersion = lint.releasedInVersion;
+            final unreleasedLint =
+                lint.sinceDartSdk == 'Unreleased' ||
+                lint.sinceDartSdk.contains('-wip') ||
+                releasedInVersion == null ||
+                releasedInVersion > runningDartVersion;
+
             return Component.fragment(
               [
                 Tags([
-                  if (lint.sinceDartSdk == 'Unreleased' ||
-                      lint.sinceDartSdk.contains('-wip'))
+                  if (unreleasedLint)
                     const Tag(
                       'Unreleased',
                       icon: 'pending',
-                      color: 'orange',
+                      color: TagColor.orange,
                       title: 'Lint is unreleased or work in progress.',
                     )
                   else if (lint.state == 'experimental')
                     const Tag(
                       'Experimental',
                       icon: 'science',
-                      color: 'orange',
+                      color: TagColor.orange,
                       title: 'Lint is experimental.',
                     )
                   else if (lint.state == 'deprecated')
                     const Tag(
                       'Deprecated',
                       icon: 'report',
-                      color: 'orange',
+                      color: TagColor.orange,
                       title: 'Lint is deprecated.',
                     )
                   else if (lint.state == 'removed')
                     const Tag(
                       'Removed',
                       icon: 'error',
-                      color: 'red',
+                      color: TagColor.red,
                       title: 'Lint has been removed.',
                     )
                   else
                     const Tag(
                       'Stable',
                       icon: 'verified_user',
-                      color: 'green',
+                      color: TagColor.green,
                       title: 'Lint is stable.',
                     ),
 
@@ -250,6 +257,17 @@ List<MemoryPage> get _lintMemoryPages {
                       icon: 'build',
                       title: 'Lint has one or more quick fixes available.',
                     ),
+                  if (lint.sinceDartSdk != '2.0')
+                    Tag(
+                      'Released in Dart ${lint.sinceDartSdk}',
+                      icon: 'merge_type',
+                      color: TagColor.grey,
+                      title: unreleasedLint
+                          ? 'This lint is set to be '
+                                'available in Dart ${lint.sinceDartSdk}'
+                          : 'This lint was originally '
+                                'available in Dart ${lint.sinceDartSdk}.',
+                    ),
                 ]),
                 DashMarkdown(
                   content:

site/lib/src/utils/server_only_utils.dart

@@ -0,0 +1,14 @@
+// Copyright (c) 2026, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:io' show Platform;
+
+import 'package:pub_semver/pub_semver.dart' show Version;
+
+/// The Dart version running this application.
+///
+/// Can only be called on the server, not from the client.
+final Version runningDartVersion = Version.parse(
+  Platform.version.split(' ').first,
+);