feat: Allow pytest-mypy to pass mypy custom config file via flag

src/pytest_mypy.py

@@ -32,6 +32,12 @@ def pytest_addoption(parser):
  action="store_true",
  help="suppresses error messages about imports that cannot be resolved",
  )
+ group.addoption(
+ "--mypy-config-file",
+ action="store",
+ type=str,
+ help="adds custom mypy config file",
+ )
 
 
 XDIST_WORKERINPUT_ATTRIBUTE_NAMES = (
@@ -94,11 +100,19 @@ def pytest_configure_node(self, node): # xdist hook
  if config.getoption("--mypy-ignore-missing-imports"):
  mypy_argv.append("--ignore-missing-imports")
 
+ mypy_config_file = config.getoption("--mypy-config-file")
+ if mypy_config_file:
+ mypy_argv.append("--config-file={}".format(mypy_config_file))
+
 
 def pytest_collect_file(path, parent):
  """Create a MypyFileItem for every file mypy should run on."""
  if path.ext in {".py", ".pyi"} and any(
- [parent.config.option.mypy, parent.config.option.mypy_ignore_missing_imports],
+ [
+ parent.config.option.mypy,
+ parent.config.option.mypy_config_file,
+ parent.config.option.mypy_ignore_missing_imports,
+ ],
  ):
  # Do not create MypyFile instance for a .py file if a
  # .pyi file with the same name already exists;

tests/test_pytest_mypy.py

@@ -129,6 +129,34 @@ def test_mypy_ignore_missings_imports(testdir, xdist_args):
  assert result.ret == 0
 
 
+def test_mypy_config_file(testdir, xdist_args):
+ """Verify that --mypy-config-file works."""
+ testdir.makepyfile(
+ """
+ def pyfunc(x):
+ return x * 2
+ """,
+ )
+ result = testdir.runpytest_subprocess("--mypy", *xdist_args)
+ mypy_file_checks = 1
+ mypy_status_check = 1
+ mypy_checks = mypy_file_checks + mypy_status_check
+ result.assert_outcomes(passed=mypy_checks)
+ assert result.ret == 0
+ mypy_config_file = testdir.makeini(
+ """
+ [mypy]
+ disallow_untyped_defs = True
+ """,
+ )
+ result = testdir.runpytest_subprocess(
+ "--mypy-config-file",
+ mypy_config_file,
+ *xdist_args,
+ )
+ result.assert_outcomes(failed=mypy_checks)
+
+
 def test_mypy_marker(testdir, xdist_args):
  """Verify that -m mypy only runs the mypy tests."""
  testdir.makepyfile(