import re import sys import pytest from _pytest.outcomes import Failed from _pytest.pytester import Pytester class TestRaises: def test_check_callable(self) -> None: with pytest.raises(TypeError, match=r".* must be callable"): pytest.raises(RuntimeError, "int('qwe')") # type: ignore[call-overload] def test_raises(self): excinfo = pytest.raises(ValueError, int, "qwe") assert "invalid literal" in str(excinfo.value) def test_raises_function(self): excinfo = pytest.raises(ValueError, int, "hello") assert "invalid literal" in str(excinfo.value) def test_raises_does_not_allow_none(self): with pytest.raises(ValueError, match="Expected an exception type or"): # We're testing that this invalid usage gives a helpful error, # so we can ignore Mypy telling us that None is invalid. pytest.raises(expected_exception=None) # type: ignore def test_raises_does_not_allow_empty_tuple(self): with pytest.raises(ValueError, match="Expected an exception type or"): pytest.raises(expected_exception=()) def test_raises_callable_no_exception(self) -> None: class A: def __call__(self): pass try: pytest.raises(ValueError, A()) except pytest.fail.Exception: pass def test_raises_falsey_type_error(self) -> None: with pytest.raises(TypeError): with pytest.raises(AssertionError, match=0): # type: ignore[call-overload] raise AssertionError("ohai") def test_raises_repr_inflight(self): """Ensure repr() on an exception info inside a pytest.raises with block works (#4386)""" class E(Exception): pass with pytest.raises(E) as excinfo: # this test prints the inflight uninitialized object # using repr and str as well as pprint to demonstrate # it works print(str(excinfo)) print(repr(excinfo)) import pprint pprint.pprint(excinfo) raise E() def test_raises_as_contextmanager(self, pytester: Pytester) -> None: pytester.makepyfile( """ import pytest import _pytest._code def test_simple(): with pytest.raises(ZeroDivisionError) as excinfo: assert isinstance(excinfo, _pytest._code.ExceptionInfo) 1/0 print(excinfo) assert excinfo.type == ZeroDivisionError assert isinstance(excinfo.value, ZeroDivisionError) def test_noraise(): with pytest.raises(pytest.raises.Exception): with pytest.raises(ValueError): int() def test_raise_wrong_exception_passes_by(): with pytest.raises(ZeroDivisionError): with pytest.raises(ValueError): 1/0 """ ) result = pytester.runpytest() result.stdout.fnmatch_lines(["*3 passed*"]) def test_does_not_raise(self, pytester: Pytester) -> None: pytester.makepyfile( """ from contextlib import nullcontext as does_not_raise import pytest @pytest.mark.parametrize('example_input,expectation', [ (3, does_not_raise()), (2, does_not_raise()), (1, does_not_raise()), (0, pytest.raises(ZeroDivisionError)), ]) def test_division(example_input, expectation): '''Test how much I know division.''' with expectation: assert (6 / example_input) is not None """ ) result = pytester.runpytest() result.stdout.fnmatch_lines(["*4 passed*"]) def test_does_not_raise_does_raise(self, pytester: Pytester) -> None: pytester.makepyfile( """ from contextlib import nullcontext as does_not_raise import pytest @pytest.mark.parametrize('example_input,expectation', [ (0, does_not_raise()), (1, pytest.raises(ZeroDivisionError)), ]) def test_division(example_input, expectation): '''Test how much I know division.''' with expectation: assert (6 / example_input) is not None """ ) result = pytester.runpytest() result.stdout.fnmatch_lines(["*2 failed*"]) def test_noclass(self) -> None: with pytest.raises(TypeError): pytest.raises("wrong", lambda: None) # type: ignore[call-overload] def test_invalid_arguments_to_raises(self) -> None: with pytest.raises(TypeError, match="unknown"): with pytest.raises(TypeError, unknown="bogus"): # type: ignore[call-overload] raise ValueError() def test_tuple(self): with pytest.raises((KeyError, ValueError)): raise KeyError("oops") def test_no_raise_message(self) -> None: try: pytest.raises(ValueError, int, "0") except pytest.fail.Exception as e: assert e.msg == f"DID NOT RAISE {repr(ValueError)}" else: assert False, "Expected pytest.raises.Exception" try: with pytest.raises(ValueError): pass except pytest.fail.Exception as e: assert e.msg == f"DID NOT RAISE {repr(ValueError)}" else: assert False, "Expected pytest.raises.Exception" @pytest.mark.parametrize("method", ["function", "function_match", "with"]) def test_raises_cyclic_reference(self, method): """Ensure pytest.raises does not leave a reference cycle (#1965).""" import gc class T: def __call__(self): raise ValueError t = T() refcount = len(gc.get_referrers(t)) if method == "function": pytest.raises(ValueError, t) elif method == "function_match": pytest.raises(ValueError, t).match("^$") else: with pytest.raises(ValueError): t() # ensure both forms of pytest.raises don't leave exceptions in sys.exc_info() assert sys.exc_info() == (None, None, None) assert refcount == len(gc.get_referrers(t)) def test_raises_match(self) -> None: msg = r"with base \d+" with pytest.raises(ValueError, match=msg): int("asdf") msg = "with base 10" with pytest.raises(ValueError, match=msg): int("asdf") msg = "with base 16" expr = ( "Regex pattern did not match.\n" f" Regex: {msg!r}\n" " Input: \"invalid literal for int() with base 10: 'asdf'\"" ) with pytest.raises(AssertionError, match="(?m)" + re.escape(expr)): with pytest.raises(ValueError, match=msg): int("asdf", base=10) # "match" without context manager. pytest.raises(ValueError, int, "asdf").match("invalid literal") with pytest.raises(AssertionError) as excinfo: pytest.raises(ValueError, int, "asdf").match(msg) assert str(excinfo.value) == expr pytest.raises(TypeError, int, match="invalid") def tfunc(match): raise ValueError(f"match={match}") pytest.raises(ValueError, tfunc, match="asdf").match("match=asdf") pytest.raises(ValueError, tfunc, match="").match("match=") def test_match_failure_string_quoting(self): with pytest.raises(AssertionError) as excinfo: with pytest.raises(AssertionError, match="'foo"): raise AssertionError("'bar") (msg,) = excinfo.value.args assert msg == '''Regex pattern did not match.\n Regex: "'foo"\n Input: "'bar"''' def test_match_failure_exact_string_message(self): message = "Oh here is a message with (42) numbers in parameters" with pytest.raises(AssertionError) as excinfo: with pytest.raises(AssertionError, match=message): raise AssertionError(message) (msg,) = excinfo.value.args assert msg == ( "Regex pattern did not match.\n" " Regex: 'Oh here is a message with (42) numbers in parameters'\n" " Input: 'Oh here is a message with (42) numbers in parameters'\n" " Did you mean to `re.escape()` the regex?" ) def test_raises_match_wrong_type(self): """Raising an exception with the wrong type and match= given. pytest should throw the unexpected exception - the pattern match is not really relevant if we got a different exception. """ with pytest.raises(ValueError): with pytest.raises(IndexError, match="nomatch"): int("asdf") def test_raises_exception_looks_iterable(self): class Meta(type): def __getitem__(self, item): return 1 / 0 def __len__(self): return 1 class ClassLooksIterableException(Exception, metaclass=Meta): pass with pytest.raises( Failed, match=r"DID NOT RAISE ", ): pytest.raises(ClassLooksIterableException, lambda: None) def test_raises_with_raising_dunder_class(self) -> None: """Test current behavior with regard to exceptions via __class__ (#4284).""" class CrappyClass(Exception): # Type ignored because it's bypassed intentionally. @property # type: ignore def __class__(self): assert False, "via __class__" with pytest.raises(AssertionError) as excinfo: with pytest.raises(CrappyClass()): # type: ignore[call-overload] pass assert "via __class__" in excinfo.value.args[0] def test_raises_context_manager_with_kwargs(self): with pytest.raises(TypeError) as excinfo: with pytest.raises(Exception, foo="bar"): # type: ignore[call-overload] pass assert "Unexpected keyword arguments" in str(excinfo.value) def test_expected_exception_is_not_a_baseexception(self) -> None: with pytest.raises(TypeError) as excinfo: with pytest.raises("hello"): # type: ignore[call-overload] pass # pragma: no cover assert "must be a BaseException type, not str" in str(excinfo.value) class NotAnException: pass with pytest.raises(TypeError) as excinfo: with pytest.raises(NotAnException): # type: ignore[type-var] pass # pragma: no cover assert "must be a BaseException type, not NotAnException" in str(excinfo.value) with pytest.raises(TypeError) as excinfo: with pytest.raises(("hello", NotAnException)): # type: ignore[arg-type] pass # pragma: no cover assert "must be a BaseException type, not str" in str(excinfo.value)