Function test_with_resource_nested_exception

tests/test_context.py:592–660

()

def test_with_resource_nested_exception() -> None:
    class TestContext(AbstractContextManager[list[int]]):
        _handle_exception: bool
        _base_val: int
        val: list[int]

        def __init__(self, base_val: int = 1, *, handle_exception: bool = True) -> None:
            self._handle_exception = handle_exception
            self._base_val = base_val

        def __enter__(self) -> list[int]:
            self.val = [self._base_val]
            return self.val

        def __exit__(
            self,
            exc_type: type[BaseException] | None,
            exc_value: BaseException | None,
            traceback: TracebackType | None,
        ) -> bool | None:
            if not exc_type:
                self.val[0] = self._base_val - 1
                return None

            self.val[0] = self._base_val + 1
            return self._handle_exception

    class TestException(Exception):
        pass

    ctx = click.Context(click.Command("test"))
    base_val = 1
    base_val_nested = 11

    with ctx.scope():
        rv = ctx.with_resource(TestContext(base_val=base_val))
        rv_nested = ctx.with_resource(TestContext(base_val=base_val_nested))
        assert rv[0] == base_val
        assert rv_nested[0] == base_val_nested

    assert rv == [base_val - 1]
    assert rv_nested == [base_val_nested - 1]

    with ctx.scope():
        rv = ctx.with_resource(TestContext(base_val=base_val))
        rv_nested = ctx.with_resource(TestContext(base_val=base_val_nested))
        raise TestException()

    # If one of the context "eats" the exceptions they will not be forwarded to other
    # parts. This is due to how ExitStack unwinding works
    assert rv_nested == [base_val_nested + 1]
    assert rv == [base_val - 1]

    with ctx.scope():
        rv = ctx.with_resource(TestContext(base_val=base_val))
        rv_nested = ctx.with_resource(
            TestContext(base_val=base_val_nested, handle_exception=False)
        )