diff --git a/mesonpy/_tags.py b/mesonpy/_tags.py
index 60edf094d..9c09fe5a1 100644
--- a/mesonpy/_tags.py
+++ b/mesonpy/_tags.py
@@ -109,7 +109,8 @@ def _get_macosx_platform_tag() -> str:
     # Override the macOS version if one is provided via the
     # MACOSX_DEPLOYMENT_TARGET environment variable.
     try:
-        version = tuple(map(int, os.environ.get('MACOSX_DEPLOYMENT_TARGET', '').split('.')))[:2]
+        parts = os.environ.get('MACOSX_DEPLOYMENT_TARGET', '').split('.')[:2]
+        version = tuple(map(int, parts + ['0'] * (2 - len(parts))))
     except ValueError:
         version = tuple(map(int, ver.split('.')))[:2]
 
@@ -164,7 +165,8 @@ def _get_ios_platform_tag() -> str:
     # Override the iOS version if one is provided via the
     # IPHONEOS_DEPLOYMENT_TARGET environment variable.
     try:
-        version = tuple(map(int, os.environ.get('IPHONEOS_DEPLOYMENT_TARGET', '').split('.')))[:2]
+        parts = os.environ.get('IPHONEOS_DEPLOYMENT_TARGET', '').split('.')[:2]
+        version = tuple(map(int, parts + ['0'] * (2 - len(parts))))
     except ValueError:
         version = tuple(map(int, platform.ios_ver().release.split('.')))[:2]  # type: ignore[attr-defined]
 
diff --git a/tests/conftest.py b/tests/conftest.py
index b53161d61..af737968c 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -154,7 +154,7 @@ def fixture(tmp_path_session):
 def generate_wheel_fixture(package):
     @pytest.fixture(scope='session')
     def fixture(tmp_path_session):
-        with chdir(package_dir / package), in_git_repo_context():
+        with chdir(package_dir / package):
             return tmp_path_session / mesonpy.build_wheel(tmp_path_session)
     return fixture
 
@@ -163,7 +163,7 @@ def generate_editable_fixture(package):
     @pytest.fixture(scope='session')
     def fixture(tmp_path_session):
         shutil.rmtree(package_dir / package / '.mesonpy' / 'editable', ignore_errors=True)
-        with chdir(package_dir / package), in_git_repo_context():
+        with chdir(package_dir / package):
             return tmp_path_session / mesonpy.build_editable(tmp_path_session)
     return fixture
 
@@ -183,3 +183,12 @@ def disable_pip_version_check():
     mpatch = pytest.MonkeyPatch()
     yield mpatch.setenv('PIP_DISABLE_PIP_VERSION_CHECK', '1')
     mpatch.undo()
+
+
+@pytest.fixture(autouse=True, scope='session')
+def cleanenv():
+    # Cannot use the 'monkeypatch' fixture because of scope mismatch.
+    mpatch = pytest.MonkeyPatch()
+    # $MACOSX_DEPLOYMENT_TARGET affects the computation of the platform tag on macOS.
+    yield mpatch.delenv('MACOSX_DEPLOYMENT_TARGET', raising=False)
+    mpatch.undo()
diff --git a/tests/test_tags.py b/tests/test_tags.py
index bb39fd6d9..62aa61934 100644
--- a/tests/test_tags.py
+++ b/tests/test_tags.py
@@ -40,13 +40,7 @@ def get_abi3_suffix():
 ABI3SUFFIX = get_abi3_suffix()
 
 
-@pytest.fixture()
-def cleanenv(monkeypatch):
-    # $MACOSX_DEPLOYMENT_TARGET affects the computation of the platform tag on macOS.
-    monkeypatch.delenv('MACOSX_DEPLOYMENT_TARGET', raising=False)
-
-
-def test_wheel_tag(cleanenv):
+def test_wheel_tag():
     assert str(mesonpy._tags.Tag()) == f'{INTERPRETER}-{ABI}-{PLATFORM}'
     assert str(mesonpy._tags.Tag(abi='abi3')) == f'{INTERPRETER}-abi3-{PLATFORM}'
 
@@ -61,6 +55,11 @@ def test_macos_platform_tag(monkeypatch):
         for minor in range(3):
             monkeypatch.setenv('MACOSX_DEPLOYMENT_TARGET', f'{major}.{minor}')
             assert next(packaging.tags.mac_platforms((major, minor))) == mesonpy._tags.get_platform_tag()
+    for major in range(11, 13):
+        monkeypatch.setenv('MACOSX_DEPLOYMENT_TARGET', f'{major}.0')
+        assert next(packaging.tags.mac_platforms((major, 0))) == mesonpy._tags.get_platform_tag()
+        monkeypatch.setenv('MACOSX_DEPLOYMENT_TARGET', f'{major}')
+        assert next(packaging.tags.mac_platforms((major, 0))) == mesonpy._tags.get_platform_tag()
 
 
 @pytest.mark.skipif(sys.platform != 'darwin', reason='macOS specific test')
@@ -118,14 +117,14 @@ def test_tag_purelib_wheel():
     assert str(builder.tag) == 'py3-none-any'
 
 
-def test_tag_platlib_wheel(cleanenv):
+def test_tag_platlib_wheel():
     builder = wheel_builder_test_factory({
         'platlib': [f'extension{SUFFIX}'],
     })
     assert str(builder.tag) == f'{INTERPRETER}-{ABI}-{PLATFORM}'
 
 
-def test_tag_stable_abi(cleanenv):
+def test_tag_stable_abi():
     builder = wheel_builder_test_factory({
         'platlib': [f'extension{ABI3SUFFIX}'],
     }, limited_api=True)
@@ -136,7 +135,7 @@ def test_tag_stable_abi(cleanenv):
 
 @pytest.mark.xfail(sys.version_info < (3, 8) and sys.platform == 'win32', reason='Extension modules suffix without ABI tags')
 @pytest.mark.xfail('__pypy__' in sys.builtin_module_names, reason='PyPy does not support the stable ABI')
-def test_tag_mixed_abi(cleanenv):
+def test_tag_mixed_abi():
     builder = wheel_builder_test_factory({
         'platlib': [f'extension{ABI3SUFFIX}', f'another{SUFFIX}'],
     }, pure=False, limited_api=True)