Add instructions and functionality for testing new release notes

packages/devtools_app/lib/src/app.dart

@@ -44,7 +44,7 @@ import 'shared/globals.dart';
 import 'shared/initializer.dart';
 import 'shared/landing_screen.dart';
 import 'shared/notifications.dart';
-import 'shared/release_notes.dart';
+import 'shared/release_notes/release_notes.dart';
 import 'shared/routing.dart';
 import 'shared/scaffold.dart';
 import 'shared/screen.dart';

packages/devtools_app/lib/src/shared/release_notes/README.md

@@ -0,0 +1,48 @@
+## Writing DevTools release notes
+Release notes for DevTools are hosted on the flutter website (see [archive](https://docs.flutter.dev/development/tools/devtools/release-notes)).
+To add release notes for the latest release, create a PR with the appropriate changes for your release (see example
+[PR](https://github.com/flutter/website/pull/6791)).
+
+Test these changes locally before creating the PR. See [README.md](https://github.com/flutter/website/blob/main/README.md)
+for getting setup to run the Flutter website locally.
+
+One you are satisfied with the release notes, stage the Flutter website on Firebase and point the DevTools release notes
+logic to this staged url.
+
+### Staging your changes on Firebase
+In the flutter/website directory, open [_config.yml](https://github.com/flutter/website/blob/main/_config.yml#L2)
+and replace `https://docs.flutter.dev` with `https://flutter-website-dt-staging.web.app` (line 2).
+
+Then run the following rom the `website/` directory:
+```dart
+make setup;
+DISABLE_TESTS=1 make build;
+firebase deploy --project devtools-staging --only hosting
+```
+
+Once you see this message, the deployment was successful and now you can move on to the next step.
+```shell
+...
+
+✔  Deploy complete!
+
+Project Console: https://console.firebase.google.com/project/flutter-website-dt-staging/overview
+Hosting URL: https://flutter-website-dt-staging.web.app
+```
+
+### Testing the release notes in DevTools
+In `release_notes.dart` flip the `debugTestReleaseNotes` flag to true. 
+
+Then, from the main `devtools/` directory, run the following:
+```dart
+dart ./tool/build_e2e.dart
+```
+
+Once DevTools has been successfully built and served, you should see the following the CLI output:
+```shell
+...
+
+Serving DevTools with a local devtools server...
+Serving DevTools at http://127.0.0.1:57336.
+```
+Visit the DevTools link, and verify that the release notes viewer displays the new release notes as expected.

packages/devtools_app/lib/src/shared/release_notes.dart → packages/devtools_app/lib/src/shared/release_notes/release_notes.dart

@@ -11,15 +11,17 @@ import 'package:flutter/material.dart';
 import 'package:flutter_markdown/flutter_markdown.dart';
 import 'package:http/http.dart' as http;
 
-import '../../devtools.dart' as devtools;
-import '../config_specific/launch_url/launch_url.dart';
-import '../config_specific/logger/logger.dart' as logger;
-import '../config_specific/server/server.dart' as server;
-import '../primitives/auto_dispose_mixin.dart';
-import 'common_widgets.dart';
-import 'theme.dart';
-import 'utils.dart';
-import 'version.dart';
+import '../../../devtools.dart' as devtools;
+import '../../config_specific/launch_url/launch_url.dart';
+import '../../config_specific/logger/logger.dart' as logger;
+import '../../config_specific/server/server.dart' as server;
+import '../../primitives/auto_dispose_mixin.dart';
+import '../common_widgets.dart';
+import '../theme.dart';
+import '../utils.dart';
+import '../version.dart';
+
+const debugTestReleaseNotes = false;
 
 class ReleaseNotesViewer extends StatefulWidget {
   const ReleaseNotesViewer({
@@ -169,7 +171,9 @@ class ReleaseNotesController {
 
   static const _unsupportedPathSyntax = '{{site.url}}';
 
-  static const _flutterDocsSite = 'https://docs.flutter.dev';
+  String get _flutterDocsSite => debugTestReleaseNotes
+      ? 'https://flutter-website-dt-staging.web.app'
+      : 'https://docs.flutter.dev';
 
   ValueListenable<String?> get releaseNotesMarkdown => _releaseNotesMarkdown;
 
@@ -189,7 +193,7 @@ class ReleaseNotesController {
     final lastReleaseNotesShownVersion =
         await server.getLastShownReleaseNotesVersion();
     SemanticVersion previousVersion;
-    if (lastReleaseNotesShownVersion.isEmpty) {
+    if (debugTestReleaseNotes || lastReleaseNotesShownVersion.isEmpty) {
       previousVersion = SemanticVersion();
     } else {
       previousVersion = SemanticVersion.parse(lastReleaseNotesShownVersion);
@@ -238,6 +242,7 @@ class ReleaseNotesController {
   }
 
   String _releaseNotesUrl(String currentVersion) {
-    return 'https://docs.flutter.dev/development/tools/devtools/release-notes/release-notes-$currentVersion-src.md';
+    return '$_flutterDocsSite/development/tools/devtools/release-notes/'
+        'release-notes-$currentVersion-src.md';
   }
 }

tool/README.md

@@ -95,14 +95,6 @@ git rebase-update
 third_party/devtools/update.sh 8881a7caa9067471008a8e00750b161f53cdb843
 ```
 
-### Publish package:devtools_shared on pub
-
-`package:devtools_shared` is the only DevTools package that is published on pub.
-From the devtools/packages/devtools_shared directory, run:
-```shell
-pub publish
-```
-
 ### Update the DevTools hash in the Dart SDK
 
 Update the `devtools_rev` entry in the Dart SDK 
@@ -118,4 +110,19 @@ cd path/to/dart-sdk/sdk
 gclient sync -D
 ./tools/build.py -mrelease -ax64 create_sdk
 out/ReleaseX64/dart-sdk/bin/dart devtools  # On OSX replace 'out' with 'xcodebuild'
-```
+```
+
+### Publish package:devtools_shared on pub
+
+`package:devtools_shared` is the only DevTools package that is published on pub.
+From the devtools/packages/devtools_shared directory, run:
+```shell
+pub publish
+```
+
+### Write release notes for the release
+Release notes should contain details about the user-facing changes included in the release.
+These notes are shown directly in DevTools when a user opens a new version of DevTools. Please
+see the release notes
+[README.md](https://github.com/flutter/devtools/blob/master/packages/devtools_app/lib/src/shared/release_notes/README.md)
+for details on where to add release notes and how to test them.