assertions.py 文件源码

def emits_warning_on(db, *messages):
    """Mark a test as emitting a warning on a specific dialect.

    With no arguments, squelches all SAWarning failures.  Or pass one or more
    strings; these will be matched to the root of the warning description by
    warnings.filterwarnings().

    Note that emits_warning_on does **not** assert that the warnings
    were in fact seen.

    """
    @decorator
    def decorate(fn, *args, **kw):
        with expect_warnings_on(db, assert_=False, *messages):
            return fn(*args, **kw)

    return decorate