[flutter_tools] update pubspec .yaml message should not be displayed when...

[flutter_tools] update pubspec .yaml message should not be displayed when creating a new plugin (#62599)

* update pubspec message should not be displayed when creating a new plugin

* formatting

* revikew

* review

* cleanup

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

@@ -612,7 +612,9 @@ To edit platform code in an IDE see https://flutter.dev/developing-packages/#edi
       );
     }
 
-    if (willAddPlatforms) {
+    final bool addPlatformsToExistingPlugin = willAddPlatforms && existingPlatforms.isNotEmpty;
+
+    if (addPlatformsToExistingPlugin) {
       // If adding new platforms to an existing plugin project, prints
       // a help message containing the platforms maps need to be added to the `platforms` key in the pubspec.
       platformsToAdd.removeWhere(existingPlatforms.contains);

packages/flutter_tools/test/commands.shard/permeable/create_test.dart

@@ -10,6 +10,7 @@ import 'package:args/command_runner.dart';
 import 'package:flutter_tools/src/artifacts.dart';
 import 'package:flutter_tools/src/base/file_system.dart';
 import 'package:flutter_tools/src/base/io.dart';
+import 'package:flutter_tools/src/base/logger.dart';
 import 'package:flutter_tools/src/base/net.dart';
 import 'package:flutter_tools/src/base/platform.dart';
 import 'package:flutter_tools/src/build_info.dart';
@@ -47,6 +48,7 @@ void main() {
   Directory projectDir;
   FlutterVersion mockFlutterVersion;
   LoggingProcessManager loggingProcessManager;
+  BufferLogger logger;
 
   setUpAll(() async {
     Cache.disableLocking();
@@ -55,6 +57,7 @@ void main() {
 
   setUp(() {
     loggingProcessManager = LoggingProcessManager();
+    logger = BufferLogger.test();
     tempDir = globals.fs.systemTempDirectory.createTempSync('flutter_tools_create_test.');
     projectDir = tempDir.childDirectory('flutter_project');
     mockFlutterVersion = MockFlutterVersion();
@@ -1935,6 +1938,34 @@ void main() {
     FeatureFlags: () => TestFeatureFlags(isMacOSEnabled: true),
   });
 
+  testUsingContext('flutter create -t plugin in an empty folder should not show pubspec.yaml updating suggestion', () async {
+    Cache.flutterRoot = '../..';
+    when(mockFlutterVersion.frameworkRevision).thenReturn(frameworkRevision);
+    when(mockFlutterVersion.channel).thenReturn(frameworkChannel);
+
+    final CreateCommand command = CreateCommand();
+    final CommandRunner<void> runner = createTestCommandRunner(command);
+    await runner.run(<String>['create', '--no-pub', '--template=plugin', '--platforms=android', projectDir.path]);
+    expect(logger.statusText, isNot(contains('The `pubspec.yaml` under the project directory must be updated to support')));
+  }, overrides: <Type, Generator> {
+    Logger: () => logger,
+  });
+
+  testUsingContext('flutter create -t plugin in an existing plugin should show pubspec.yaml updating suggestion', () async {
+    Cache.flutterRoot = '../..';
+    when(mockFlutterVersion.frameworkRevision).thenReturn(frameworkRevision);
+    when(mockFlutterVersion.channel).thenReturn(frameworkChannel);
+
+    final CreateCommand command = CreateCommand();
+    final CommandRunner<void> runner = createTestCommandRunner(command);
+    await runner.run(<String>['create', '--no-pub', '--template=plugin', '--platforms=ios', projectDir.path]);
+    expect(logger.statusText, isNot(contains('The `pubspec.yaml` under the project directory must be updated to support')));
+    await runner.run(<String>['create', '--no-pub', '--template=plugin', '--platforms=android', projectDir.path]);
+    expect(logger.statusText, contains('The `pubspec.yaml` under the project directory must be updated to support'));
+  }, overrides: <Type, Generator> {
+    Logger: () => logger,
+  });
+
 }
 
 Future<void> _createProject(