Expose `packagePath` as a getter in FlutterCommand. (#80026)

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

@@ -283,6 +283,11 @@ abstract class FlutterCommand extends Command<void> {
     return bundle.defaultMainPath;
   }
 
+  /// Path to the Dart's package config file.
+  ///
+  /// This can be overridden by some of its subclasses.
+  String get packagesPath => globalResults['packages'] as String;
+
   void usesPubOption({bool hide = false}) {
     argParser.addFlag('pub',
       defaultsTo: true,
@@ -845,7 +850,7 @@ abstract class FlutterCommand extends Command<void> {
       : null;
 
     final File packagesFile = globals.fs.file(
-      globalResults['packages'] as String ?? globals.fs.path.absolute('.dart_tool', 'package_config.json'));
+      packagesPath ?? globals.fs.path.absolute('.dart_tool', 'package_config.json'));
     final PackageConfig packageConfig = await loadPackageConfigWithLogging(
         packagesFile, logger: globals.logger, throwOnError: false);
 
@@ -989,8 +994,7 @@ abstract class FlutterCommand extends Command<void> {
       bundleSkSLPath: bundleSkSLPath,
       dartExperiments: experiments,
       performanceMeasurementFile: performanceMeasurementFile,
-      packagesPath: globalResults['packages'] as String
-        ?? globals.fs.path.absolute('.dart_tool', 'package_config.json'),
+      packagesPath: packagesPath ?? globals.fs.path.absolute('.dart_tool', 'package_config.json'),
       nullSafetyMode: nullSafetyMode,
       codeSizeDirectory: codeSizeDirectory,
       androidGradleDaemon: androidGradleDaemon,

packages/flutter_tools/test/general.shard/runner/flutter_command_test.dart

@@ -15,6 +15,7 @@ import 'package:flutter_tools/src/base/file_system.dart';
 import 'package:flutter_tools/src/base/io.dart';
 import 'package:flutter_tools/src/base/signals.dart';
 import 'package:flutter_tools/src/base/time.dart';
+import 'package:flutter_tools/src/build_info.dart';
 import 'package:flutter_tools/src/cache.dart';
 import 'package:flutter_tools/src/dart/pub.dart';
 import 'package:flutter_tools/src/reporting/reporting.dart';
@@ -540,6 +541,12 @@ void main() {
       FileSystem: () => MemoryFileSystem.test(),
       ProcessManager: () => FakeProcessManager.any(),
     });
+
+    testUsingContext('use packagesPath to generate BuildInfo', () async {
+      final DummyFlutterCommand flutterCommand = DummyFlutterCommand(packagesPath: 'foo');
+      final BuildInfo buildInfo = await flutterCommand.getBuildInfo(forcedBuildMode: BuildMode.debug);
+      expect(buildInfo.packagesPath, 'foo');
+    });
   });
 }
 

packages/flutter_tools/test/general.shard/runner/utils.dart

@@ -15,6 +15,7 @@ class DummyFlutterCommand extends FlutterCommand {
     this.noUsagePath  = false,
     this.name = 'dummy',
     this.commandFunction,
+    this.packagesPath,
   });
 
   final bool noUsagePath;
@@ -36,4 +37,7 @@ class DummyFlutterCommand extends FlutterCommand {
   Future<FlutterCommandResult> runCommand() async {
     return commandFunction == null ? FlutterCommandResult.fail() : await commandFunction();
   }
+
+  @override
+  final String packagesPath;
 }