Support safe.bareRepository=explicit (#4776)

test/git_test.dart

diff --git a/test/git_test.dart b/test/git_test.dart
index 6404988..2ddf65b 100644
--- a/test/git_test.dart
+++ b/test/git_test.dart
@@ -5,11 +5,15 @@
 @TestOn('vm')
 library;
 
+import 'dart:io';
 import 'dart:typed_data';
 
 import 'package:pub/src/git.dart';
 import 'package:test/test.dart';
 
+import 'descriptor.dart';
+import 'test_pub.dart';
+
 void main() {
   test('splitZeroTerminated works', () {
     expect(splitZeroTerminated(Uint8List.fromList([])), <Uint8List>[]);
@@ -47,4 +51,28 @@
       throwsA(isA<FormatException>()),
     );
   });
+
+  test('safe.bareRepository is enabled by default in test environment', () {
+    // Regression protection for https://github.com/dart-lang/pub/issues/4770.
+    final r = Process.runSync('git', [
+      'config',
+      '--get',
+      'safe.bareRepository',
+    ], environment: getPubTestEnvironment());
+    expect(r.stdout, contains('explicit'));
+    Process.runSync(
+      'git',
+      ['init', '--bare'],
+      workingDirectory: sandbox,
+      environment: getPubTestEnvironment(),
+    );
+    final r1 = Process.runSync(
+      'git',
+      ['log'],
+      workingDirectory: sandbox,
+      environment: getPubTestEnvironment(),
+    );
+    expect(r1.exitCode, isNot(0));
+    expect(r1.stderr, contains('fatal: cannot use bare repository '));
+  });
 }

test/test_pub.dart

diff --git a/test/test_pub.dart b/test/test_pub.dart
index a4adec3..9aa9343 100644
--- a/test/test_pub.dart
+++ b/test/test_pub.dart
@@ -467,6 +467,9 @@
   if (tokenEndpoint != null) '_PUB_TEST_TOKEN_ENDPOINT': tokenEndpoint,
   if (_globalServer?.port != null)
     'PUB_HOSTED_URL': 'http://localhost:${_globalServer?.port}',
+  'GIT_CONFIG_COUNT': '1',
+  'GIT_CONFIG_KEY_0': 'safe.bareRepository',
+  'GIT_CONFIG_VALUE_0': 'explicit',
 };
 
 /// The path to the root of pub's sources in the pub repo.