Function ignore_warnings

sklearn/utils/_testing.py:73–114

Context manager and decorator to ignore warnings. Note: Using this (in both variants) will clear all warnings from all python modules loaded. In case you need to test cross-module-warning-logging, this is not your tool of choice. Parameters ---------- obj : callable, defaul

(obj=None, category=Warning)

def ignore_warnings(obj=None, category=Warning):
    """Context manager and decorator to ignore warnings.

    Note: Using this (in both variants) will clear all warnings
    from all python modules loaded. In case you need to test
    cross-module-warning-logging, this is not your tool of choice.

    Parameters
    ----------
    obj : callable, default=None
        callable where you want to ignore the warnings.
    category : warning class, default=Warning
        The category to filter. If Warning, all categories will be muted.

    Examples
    --------
    >>> import warnings
    >>> from sklearn.utils._testing import ignore_warnings
    >>> with ignore_warnings():
    ...     warnings.warn('buhuhuhu')

    >>> def nasty_warn():
    ...     warnings.warn('buhuhuhu')
    ...     print(42)

    >>> ignore_warnings(nasty_warn)()
    42
    """
    if isinstance(obj, type) and issubclass(obj, Warning):
        # Avoid common pitfall of passing category as the first positional
        # argument which result in the test not being run
        warning_name = obj.__name__
        raise ValueError(
            "'obj' should be a callable where you want to ignore warnings. "
            "You passed a warning class instead: 'obj={warning_name}'. "
            "If you want to pass a warning class to ignore_warnings, "
            "you should use 'category={warning_name}'".format(warning_name=warning_name)
        )
    elif callable(obj):
        return _IgnoreWarnings(category=category)(obj)
    else:
        return _IgnoreWarnings(category=category)


class _IgnoreWarnings: