Copy the flutter version JSON file into the simulated Flutter SDK used by update_packages (#143035)

Dart pub now expects that file to be present in a Flutter SDK (see
https://dart.googlesource.com/pub/+/dce232ec195df802a730eb3a66163e28d2ec6444)

packages/flutter_tools/lib/src/commands/update_packages.dart

@@ -19,6 +19,7 @@ import '../globals.dart' as globals;
 import '../project.dart';
 import '../runner/flutter_command.dart';
 import '../update_packages_pins.dart';
+import '../version.dart';
 
 class UpdatePackagesCommand extends FlutterCommand {
   UpdatePackagesCommand() {
@@ -1713,6 +1714,10 @@ Directory createTemporaryFlutterSdk(
   // Fill in version info.
   realFlutter.childFile('version')
     .copySync(directory.childFile('version').path);
+  final File versionJson = FlutterVersion.getVersionFile(realFlutter.fileSystem, realFlutter.path);
+  final Directory binCacheDirectory = directory.childDirectory('bin').childDirectory('cache');
+  binCacheDirectory.createSync(recursive: true);
+  versionJson.copySync(binCacheDirectory.childFile('flutter.version.json').path);
 
   // Directory structure should mirror the current Flutter SDK
   final Directory packages = directory.childDirectory('packages');

packages/flutter_tools/test/commands.shard/hermetic/update_packages_test.dart

@@ -73,6 +73,20 @@ dependencies:
 # PUBSPEC CHECKSUM: 6543
 ''';
 
+const String kVersionJson = '''
+{
+  "frameworkVersion": "1.2.3",
+  "channel": "[user-branch]",
+  "repositoryUrl": "git@github.com:flutter/flutter.git",
+  "frameworkRevision": "1234567812345678123456781234567812345678",
+  "frameworkCommitDate": "2024-02-06 22:26:52 +0100",
+  "engineRevision": "abcdef01abcdef01abcdef01abcdef01abcdef01",
+  "dartSdkVersion": "1.2.3",
+  "devToolsVersion": "1.2.3",
+  "flutterVersion": "1.2.3"
+}
+''';
+
 void main() {
   group('update-packages', () {
     late FileSystem fileSystem;
@@ -91,6 +105,9 @@ void main() {
       fileSystem = MemoryFileSystem.test();
       flutterSdk = fileSystem.directory('flutter')..createSync();
       flutterSdk.childFile('version').writeAsStringSync('1.2.3');
+      flutterSdk.childDirectory('bin').childDirectory('cache').childFile('flutter.version.json')
+        ..createSync(recursive: true)
+        ..writeAsStringSync(kVersionJson);
       flutter = flutterSdk.childDirectory('packages').childDirectory('flutter')
         ..createSync(recursive: true);
       flutterSdk.childDirectory('dev').createSync(recursive: true);

packages/flutter_tools/test/general.shard/update_packages_test.dart

@@ -77,6 +77,20 @@ dependencies:
     git:
 ''';
 
+const String kVersionJson = '''
+{
+  "frameworkVersion": "1.2.3",
+  "channel": "[user-branch]",
+  "repositoryUrl": "git@github.com:flutter/flutter.git",
+  "frameworkRevision": "1234567812345678123456781234567812345678",
+  "frameworkCommitDate": "2024-02-06 22:26:52 +0100",
+  "engineRevision": "abcdef01abcdef01abcdef01abcdef01abcdef01",
+  "dartSdkVersion": "1.2.3",
+  "devToolsVersion": "1.2.3",
+  "flutterVersion": "1.2.3"
+}
+''';
+
 void main() {
   late FileSystem fileSystem;
   late Directory flutterSdk;
@@ -88,6 +102,10 @@ void main() {
     flutterSdk = fileSystem.directory('flutter')..createSync();
     // Create version file
     flutterSdk.childFile('version').writeAsStringSync('1.2.3');
+    // Create version JSON file
+    flutterSdk.childDirectory('bin').childDirectory('cache').childFile('flutter.version.json')
+      ..createSync(recursive: true)
+      ..writeAsStringSync(kVersionJson);
     // Create a pubspec file
     flutter = flutterSdk.childDirectory('packages').childDirectory('flutter')
       ..createSync(recursive: true);
@@ -144,6 +162,7 @@ void main() {
     // The version file exists.
     expect(result.childFile('version'), exists);
     expect(result.childFile('version').readAsStringSync(), '1.2.3');
+    expect(fileSystem.file(fileSystem.path.join(result.path, 'bin', 'cache', 'flutter.version.json')), exists);
 
     // The sky_engine package exists
     expect(fileSystem.directory('${result.path}/bin/cache/pkg/sky_engine'), exists);