Add windowsIdentifier template parameter (#82588)

Windows package identifiers are globally unique strings, typically a
GUID. These are required for templates that require a Windows package
name as described in
https://docs.microsoft.com/en-us/windows/win32/appxpkg/appx-portal

Fixes https://github.com/flutter/flutter/issues/82587

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

@@ -423,9 +423,10 @@ Your $application code is in $relativeAppMain.
     final String androidPluginIdentifier = templateContext['androidIdentifier'] as String;
     final String exampleProjectName = projectName + '_example';
     templateContext['projectName'] = exampleProjectName;
-    templateContext['androidIdentifier'] = createAndroidIdentifier(organization, exampleProjectName);
-    templateContext['iosIdentifier'] = createUTIIdentifier(organization, exampleProjectName);
-    templateContext['macosIdentifier'] = createUTIIdentifier(organization, exampleProjectName);
+    templateContext['androidIdentifier'] = CreateBase.createAndroidIdentifier(organization, exampleProjectName);
+    templateContext['iosIdentifier'] = CreateBase.createUTIIdentifier(organization, exampleProjectName);
+    templateContext['macosIdentifier'] = CreateBase.createUTIIdentifier(organization, exampleProjectName);
+    templateContext['windowsIdentifier'] = CreateBase.createWindowsIdentifier(organization, exampleProjectName);
     templateContext['description'] = 'Demonstrates how to use the $projectName plugin.';
     templateContext['pluginProjectName'] = projectName;
     templateContext['androidPluginIdentifier'] = androidPluginIdentifier;

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

@@ -340,6 +340,8 @@ abstract class CreateBase extends FlutterCommand {
         createUTIIdentifier(organization, projectName);
     final String androidIdentifier =
         createAndroidIdentifier(organization, projectName);
+    final String windowsIdentifier =
+        createWindowsIdentifier(organization, projectName);
     // Linux uses the same scheme as the Android identifier.
     // https://developer.gnome.org/gio/stable/GApplication.html#g-application-id-is-valid
     final String linuxIdentifier = androidIdentifier;
@@ -351,6 +353,7 @@ abstract class CreateBase extends FlutterCommand {
       'iosIdentifier': appleIdentifier,
       'macosIdentifier': appleIdentifier,
       'linuxIdentifier': linuxIdentifier,
+      'windowsIdentifier': windowsIdentifier,
       'description': projectDescription,
       'dartSdk': '$flutterRoot/bin/cache/dart-sdk',
       'androidMinApiLevel': android_common.minApiLevel,
@@ -444,8 +447,7 @@ abstract class CreateBase extends FlutterCommand {
   ///
   /// Android application ID is specified in: https://developer.android.com/studio/build/application-id
   /// All characters must be alphanumeric or an underscore [a-zA-Z0-9_].
-  @protected
-  String createAndroidIdentifier(String organization, String name) {
+  static String createAndroidIdentifier(String organization, String name) {
     String tmpIdentifier = '$organization.$name';
     final RegExp disallowed = RegExp(r'[^\w\.]');
     tmpIdentifier = tmpIdentifier.replaceAll(disallowed, '');
@@ -470,14 +472,20 @@ abstract class CreateBase extends FlutterCommand {
     return prefixedSegments.join('.');
   }
 
+  /// Creates a Windows package name.
+  ///
+  /// Package names must be a globally unique, commonly a GUID.
+  static String createWindowsIdentifier(String organization, String name) {
+    return const Uuid().v4().toUpperCase();
+  }
+
   String _createPluginClassName(String name) {
     final String camelizedName = camelCase(name);
     return camelizedName[0].toUpperCase() + camelizedName.substring(1);
   }
 
   /// Create a UTI (https://en.wikipedia.org/wiki/Uniform_Type_Identifier) from a base name
-  @protected
-  String createUTIIdentifier(String organization, String name) {
+  static String createUTIIdentifier(String organization, String name) {
     name = camelCase(name);
     String tmpIdentifier = '$organization.$name';
     final RegExp disallowed = RegExp(r'[^a-zA-Z0-9\-\.\u0080-\uffff]+');

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

@@ -18,6 +18,7 @@ import 'package:flutter_tools/src/base/platform.dart';
 import 'package:flutter_tools/src/build_info.dart';
 import 'package:flutter_tools/src/cache.dart';
 import 'package:flutter_tools/src/commands/create.dart';
+import 'package:flutter_tools/src/commands/create_base.dart';
 import 'package:flutter_tools/src/dart/pub.dart';
 import 'package:flutter_tools/src/features.dart';
 import 'package:flutter_tools/src/globals.dart' as globals;
@@ -26,6 +27,7 @@ import 'package:flutter_tools/src/version.dart';
 import 'package:process/process.dart';
 import 'package:pub_semver/pub_semver.dart';
 import 'package:pubspec_parse/pubspec_parse.dart';
+import 'package:uuid/uuid.dart';
 
 import '../../src/common.dart';
 import '../../src/context.dart';
@@ -83,6 +85,28 @@ void main() {
     await _restoreFlutterToolsSnapshot();
   });
 
+  test('createAndroidIdentifier emits a valid identifier', () {
+    final String identifier = CreateBase.createAndroidIdentifier('42org', '8project');
+    expect(identifier.contains('.'), isTrue);
+
+    final RegExp startsWithLetter = RegExp(r'^[a-zA-Z][\w]*$');
+    final List<String> segments = identifier.split('.');
+    for (final String segment in segments) {
+      expect(startsWithLetter.hasMatch(segment), isTrue);
+    }
+  });
+
+  test('createUTIIdentifier emits a valid identifier', () {
+    final String identifier = CreateBase.createUTIIdentifier('org@', 'project');
+    expect(identifier.contains('.'), isTrue);
+    expect(identifier.contains('@'), isFalse);
+  });
+
+  test('createWindowsIdentifier emits a GUID', () {
+    final String identifier = CreateBase.createWindowsIdentifier('org', 'project');
+    expect(Uuid.isValidUUID(fromString: identifier), isTrue);
+  });
+
   // Verify that we create a default project ('app') that is
   // well-formed.
   testUsingContext('can create a default project', () async {