[flutter_tools] Suppress git output in flutter channel (#128475)

Fixes https://github.com/flutter/flutter/issues/128025

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

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 import '../base/common.dart';
+import '../base/process.dart';
 import '../cache.dart';
 import '../globals.dart' as globals;
 import '../runner/flutter_command.dart';
@@ -160,36 +161,35 @@ class ChannelCommand extends FlutterCommand {
 
   static Future<void> _checkout(String branchName) async {
     // Get latest refs from upstream.
-    int result = await globals.processUtils.stream(
+    RunResult runResult = await globals.processUtils.run(
       <String>['git', 'fetch'],
       workingDirectory: Cache.flutterRoot,
-      prefix: 'git: ',
     );
 
-    if (result == 0) {
-      result = await globals.processUtils.stream(
+    if (runResult.processResult.exitCode == 0) {
+      runResult = await globals.processUtils.run(
         <String>['git', 'show-ref', '--verify', '--quiet', 'refs/heads/$branchName'],
         workingDirectory: Cache.flutterRoot,
-        prefix: 'git: ',
       );
-      if (result == 0) {
+      if (runResult.processResult.exitCode == 0) {
         // branch already exists, try just switching to it
-        result = await globals.processUtils.stream(
+        runResult = await globals.processUtils.run(
           <String>['git', 'checkout', branchName, '--'],
           workingDirectory: Cache.flutterRoot,
-          prefix: 'git: ',
         );
       } else {
         // branch does not exist, we have to create it
-        result = await globals.processUtils.stream(
+        runResult = await globals.processUtils.run(
           <String>['git', 'checkout', '--track', '-b', branchName, 'origin/$branchName'],
           workingDirectory: Cache.flutterRoot,
-          prefix: 'git: ',
         );
       }
     }
-    if (result != 0) {
-      throwToolExit('Switching channels failed with error code $result.', exitCode: result);
+    if (runResult.processResult.exitCode != 0) {
+      throwToolExit(
+        'Switching channels failed\n$runResult.',
+        exitCode: runResult.processResult.exitCode,
+      );
     } else {
       // Remove the version check stamp, since it could contain out-of-date
       // information that pertains to the previous channel.

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

@@ -276,7 +276,7 @@ void main() {
           command: <String>['git', 'show-ref', '--verify', '--quiet', 'refs/heads/stable'],
         ),
         FakeCommand(
-            command: <String>['git', 'checkout', 'stable', '--']
+          command: <String>['git', 'checkout', 'stable', '--'],
         ),
         FakeCommand(
           command: <String>['bin/flutter', '--no-color', '--no-version-check', 'precache'],

packages/flutter_tools/test/src/fake_process_manager.dart

@@ -33,6 +33,7 @@ class FakeCommand {
     this.stdin,
     this.exception,
     this.outputFollowsExit = false,
+    this.processStartMode,
   });
 
   /// The exact commands that must be matched for this [FakeCommand] to be
@@ -102,14 +103,20 @@ class FakeCommand {
   /// [Future] on [io.Process] completes.
   final bool outputFollowsExit;
 
+  final io.ProcessStartMode? processStartMode;
+
   void _matches(
     List<String> command,
     String? workingDirectory,
     Map<String, String>? environment,
     Encoding? encoding,
+    io.ProcessStartMode? mode,
   ) {
     final List<dynamic> matchers = this.command.map((Pattern x) => x is String ? x : matches(x)).toList();
     expect(command, matchers);
+    if (processStartMode != null) {
+      expect(mode, processStartMode);
+    }
     if (this.workingDirectory != null) {
       expect(workingDirectory, this.workingDirectory);
     }
@@ -267,18 +274,26 @@ abstract class FakeProcessManager implements ProcessManager {
     String? workingDirectory,
     Map<String, String>? environment,
     Encoding? encoding,
+    io.ProcessStartMode? mode,
   );
 
   int _pid = 9999;
 
   FakeProcess _runCommand(
-    List<String> command,
+    List<String> command, {
     String? workingDirectory,
     Map<String, String>? environment,
     Encoding? encoding,
-  ) {
+    io.ProcessStartMode? mode,
+  }) {
     _pid += 1;
-    final FakeCommand fakeCommand = findCommand(command, workingDirectory, environment, encoding);
+    final FakeCommand fakeCommand = findCommand(
+      command,
+      workingDirectory,
+      environment,
+      encoding,
+      mode,
+    );
     if (fakeCommand.exception != null) {
       assert(fakeCommand.exception is Exception || fakeCommand.exception is Error);
       throw fakeCommand.exception!; // ignore: only_throw_errors
@@ -305,9 +320,15 @@ abstract class FakeProcessManager implements ProcessManager {
     Map<String, String>? environment,
     bool includeParentEnvironment = true, // ignored
     bool runInShell = false, // ignored
-    io.ProcessStartMode mode = io.ProcessStartMode.normal, // ignored
+    io.ProcessStartMode mode = io.ProcessStartMode.normal,
   }) {
-    final FakeProcess process = _runCommand(command.cast<String>(), workingDirectory, environment, io.systemEncoding);
+    final FakeProcess process = _runCommand(
+      command.cast<String>(),
+      workingDirectory: workingDirectory,
+      environment: environment,
+      encoding: io.systemEncoding,
+      mode: mode,
+    );
     if (process._completer != null) {
       _fakeRunningProcesses[process.pid] = process;
       process.exitCode.whenComplete(() {
@@ -327,7 +348,12 @@ abstract class FakeProcessManager implements ProcessManager {
     Encoding? stdoutEncoding = io.systemEncoding,
     Encoding? stderrEncoding = io.systemEncoding,
   }) async {
-    final FakeProcess process = _runCommand(command.cast<String>(), workingDirectory, environment, stdoutEncoding);
+    final FakeProcess process = _runCommand(
+      command.cast<String>(),
+      workingDirectory: workingDirectory,
+      environment: environment,
+      encoding: stdoutEncoding,
+    );
     await process.exitCode;
     return io.ProcessResult(
       process.pid,
@@ -347,7 +373,12 @@ abstract class FakeProcessManager implements ProcessManager {
     Encoding? stdoutEncoding = io.systemEncoding,
     Encoding? stderrEncoding = io.systemEncoding,
   }) {
-    final FakeProcess process = _runCommand(command.cast<String>(), workingDirectory, environment, stdoutEncoding);
+    final FakeProcess process = _runCommand(
+      command.cast<String>(),
+      workingDirectory: workingDirectory,
+      environment: environment,
+      encoding: stdoutEncoding,
+    );
     return io.ProcessResult(
       process.pid,
       process._exitCode,
@@ -385,12 +416,14 @@ class _FakeAnyProcessManager extends FakeProcessManager {
     String? workingDirectory,
     Map<String, String>? environment,
     Encoding? encoding,
+    io.ProcessStartMode? mode,
   ) {
     return FakeCommand(
       command: command,
       workingDirectory: workingDirectory,
       environment: environment,
       encoding: encoding,
+      processStartMode: mode,
     );
   }
 
@@ -415,12 +448,13 @@ class _SequenceProcessManager extends FakeProcessManager {
     String? workingDirectory,
     Map<String, String>? environment,
     Encoding? encoding,
+    io.ProcessStartMode? mode,
   ) {
     expect(_commands, isNotEmpty,
       reason: 'ProcessManager was told to execute $command (in $workingDirectory) '
               'but the FakeProcessManager.list expected no more processes.'
     );
-    _commands.first._matches(command, workingDirectory, environment, encoding);
+    _commands.first._matches(command, workingDirectory, environment, encoding, mode);
     return _commands.removeAt(0);
   }