How to Patch Globally In Pytest?

To patch globally in pytest, you can use the pytest.fixture decorator with the autouse=True parameter. This will apply the patch to all test functions automatically. You can also use the pytest.fixture decorator with the scope="session" parameter to apply the patch globally for the entire test session. Additionally, you can use the pytest.monkeypatch fixture to patch globally by applying the patch using the monkeypatch argument in your test functions. This allows you to manipulate global variables or functions in your test suite. Overall, patching globally in pytest can be achieved using fixtures and monkeypatching techniques to customize the behavior of your test environment.

How to apply patches only to specific test modules globally in pytest?

To apply patches only to specific test modules globally in pytest, you can use the pytest fixtures and monkeypatch module. Here's how you can do it:

1. Create a fixture in your conftest.py file that uses the monkeypatch fixture provided by pytest:

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import pytest

@pytest.fixture(autouse=True)
def apply_patches_for_specific_modules(monkeypatch):
    if "module_to_patch" in str(pytest.config.getoption("rootdir")):
        # Apply your patches here

1. In the apply_patches_for_specific_modules fixture, check if the test module being executed is the one you want to apply patches to. You can do this by checking the pytest.config.getoption("rootdir") attribute, which gives you the path of the test module being executed.
2. If the test module matches the one you want to patch, then you can apply your patches using the monkeypatch fixture provided by pytest.
3. Now, whenever a test is executed, pytest will automatically apply the patches only to the specific module you specified.

By following these steps, you can apply patches only to specific test modules globally in pytest.

What is the scope of global patches in pytest?

Global patches in pytest allow you to modify existing objects or functions at a global level within your test suite. This means that any test within the suite that uses the patched object or function will have the modifications applied. This can be useful for situations where you need to consistently modify behavior across multiple tests or modules.

How to handle exceptions when global patches fail in pytest?

When global patches fail in pytest, you can handle the exceptions by using the pytest.raises() context manager or the try-except block. Here's how you can handle exceptions when global patches fail in pytest:

1. Using pytest.raises():

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import pytest

def test_global_patch_failure():
    with pytest.raises(Exception):
        # Code that triggers the global patch failure

1. Using try-except block:

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def test_global_patch_failure():
    try:
        # Code that triggers the global patch failure
    except Exception as e:
        assert False, f"Global patch failed with exception: {e}"

By using either of these methods, you can ensure that your test cases handle exceptions properly when global patches fail in pytest.