import pytest
import tempfile
import os

@pytest.fixture
def temp_git_repo():
    """Create a temporary git repository."""
    with tempfile.TemporaryDirectory() as tmpdir:
        os.chdir(tmpdir)
        os.system('git init')
        yield tmpdir

@pytest.fixture
def sample_diff():
    """Sample diff for testing."""
    return """diff --git a/main.py b/main.py
index 1234567..abcdefg 100644
--- a/main.py
+++ b/main.py
@@ -1,3 +1,4 @@
 def hello():
+    print("Hello, World!")
     return "Hello"
"""