diff --git a/tests/conftest.py b/tests/conftest.py
index f92cfc1..20842b1 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -6,5 +6,12 @@ from pre_commit_hooks.util import cmd_output
 @pytest.fixture
 def temp_git_dir(tmpdir):
     git_dir = tmpdir.join('gits')
-    cmd_output('git', 'init', '--', str(git_dir))
+    cmd_output(
+        'git',
+        '-c',
+        'init.defaultBranch=master',
+        'init',
+        '--',
+        str(git_dir),
+    )
     yield git_dir