Add an option to specify the output for code size intermediate files (#80310)

packages/flutter_tools/lib/src/runner/flutter_command.dart

@@ -115,6 +115,7 @@ class FlutterOptions {
   static const String kDeviceUser = 'device-user';
   static const String kDeviceTimeout = 'device-timeout';
   static const String kAnalyzeSize = 'analyze-size';
+  static const String kCodeSizeDirectory = 'code-size-directory';
   static const String kNullAssertions = 'null-assertions';
   static const String kAndroidGradleDaemon = 'android-gradle-daemon';
   static const String kDeferredComponents = 'deferred-components';
@@ -831,8 +832,16 @@ abstract class FlutterCommand extends Command<void> {
             'This flag is only supported on "--release" builds. When building for Android, a single '
             'ABI must be specified at a time with the "--target-platform" flag. When building for iOS, '
             'only the symbols from the arm64 architecture are used to analyze code size.\n'
+            'By default, the intermediate output files will be placed in a transient directory in the '
+            'build directory. This can be overriden with the "--${FlutterOptions.kCodeSizeDirectory}" option.\n'
             'This flag cannot be combined with "--${FlutterOptions.kSplitDebugInfoOption}".'
     );
+
+    argParser.addOption(
+      FlutterOptions.kCodeSizeDirectory,
+      help: 'The location to write code size analysis files. If this is not specified, files '
+            'are written to a temporary directory under the build directory.'
+    );
   }
 
   /// Compute the [BuildInfo] for the current flutter command.
@@ -877,10 +886,13 @@ abstract class FlutterCommand extends Command<void> {
 
     String codeSizeDirectory;
     if (argParser.options.containsKey(FlutterOptions.kAnalyzeSize) && boolArg(FlutterOptions.kAnalyzeSize)) {
-      final Directory directory = globals.fsUtils.getUniqueDirectory(
+      Directory directory = globals.fsUtils.getUniqueDirectory(
         globals.fs.directory(getBuildDirectory()),
         'flutter_size',
       );
+      if (argParser.options.containsKey(FlutterOptions.kCodeSizeDirectory) && stringArg(FlutterOptions.kCodeSizeDirectory) != null) {
+        directory = globals.fs.directory(stringArg(FlutterOptions.kCodeSizeDirectory));
+      }
       directory.createSync(recursive: true);
       codeSizeDirectory = directory.path;
     }

packages/flutter_tools/test/integration.shard/analyze_size_test.dart

@@ -4,6 +4,7 @@
 
 // @dart = 2.8
 
+import 'package:file/file.dart';
 import 'package:file_testing/file_testing.dart';
 import 'package:flutter_tools/src/base/io.dart';
 
@@ -117,4 +118,27 @@ void main() {
 
     expect(result.exitCode, 1);
   });
+
+  testWithoutContext('--analyze-size allows overriding the directory for code size files', () async {
+    final String flutterBin = fileSystem.path.join(getFlutterRoot(), 'bin', 'flutter');
+    final Directory tempDir = fileSystem.systemTempDirectory.createTempSync('size_test');
+
+    final ProcessResult result = await processManager.run(<String>[
+      flutterBin,
+       ...getLocalEngineArguments(),
+      'build',
+      'apk',
+      '--analyze-size',
+      '--code-size-directory=${tempDir.path}',
+      '--target-platform=android-arm64',
+      '--release',
+    ], workingDirectory: fileSystem.path.join(getFlutterRoot(), 'examples', 'hello_world'));
+
+    expect(result.exitCode, 0);
+    expect(tempDir.existsSync(), true);
+    expect(tempDir.childFile('snapshot.arm64-v8a.json').existsSync(), true);
+    expect(tempDir.childFile('trace.arm64-v8a.json').existsSync(), true);
+
+    tempDir.deleteSync(recursive: true);
+  });
 }

packages/flutter_tools/test/src/common.dart

@@ -164,7 +164,7 @@ void test(String description, FutureOr<void> Function() body, {
 
 /// Executes a test body in zone that does not allow context-based injection.
 ///
-/// For classes which have been refactored to excluded context-based injection
+/// For classes which have been refactored to exclude context-based injection
 /// or globals like [fs] or [platform], prefer using this test method as it
 /// will prevent accidentally including these context getters in future code
 /// changes.