Uploaded Test files

venv/Lib/site-packages/traitlets/tests/_warnings.py

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+# From scikit-image: https://github.com/scikit-image/scikit-image/blob/c2f8c4ab123ebe5f7b827bc495625a32bb225c10/skimage/_shared/_warnings.py
+# Licensed under modified BSD license
+
+__all__ = ['all_warnings', 'expected_warnings']
+
+from contextlib import contextmanager
+import sys
+import warnings
+import inspect
+import re
+
+
+@contextmanager
+def all_warnings():
+    """
+    Context for use in testing to ensure that all warnings are raised.
+    Examples
+    --------
+    >>> import warnings
+    >>> def foo():
+    ...     warnings.warn(RuntimeWarning("bar"))
+    We raise the warning once, while the warning filter is set to "once".
+    Hereafter, the warning is invisible, even with custom filters:
+    >>> with warnings.catch_warnings():
+    ...     warnings.simplefilter('once')
+    ...     foo()
+    We can now run ``foo()`` without a warning being raised:
+    >>> from numpy.testing import assert_warns
+    >>> foo()
+    To catch the warning, we call in the help of ``all_warnings``:
+    >>> with all_warnings():
+    ...     assert_warns(RuntimeWarning, foo)
+    """
+
+    # Whenever a warning is triggered, Python adds a __warningregistry__
+    # member to the *calling* module.  The exercize here is to find
+    # and eradicate all those breadcrumbs that were left lying around.
+    #
+    # We proceed by first searching all parent calling frames and explicitly
+    # clearing their warning registries (necessary for the doctests above to
+    # pass).  Then, we search for all submodules of skimage and clear theirs
+    # as well (necessary for the skimage test suite to pass).
+
+    frame = inspect.currentframe()
+    if frame:
+        for f in inspect.getouterframes(frame):
+            f[0].f_locals['__warningregistry__'] = {}
+    del frame
+
+    for mod_name, mod in list(sys.modules.items()):
+        if 'six.moves' in mod_name:
+            continue
+        try:
+            mod.__warningregistry__.clear()
+        except AttributeError:
+            pass
+
+    with warnings.catch_warnings(record=True) as w:
+        warnings.simplefilter("always")
+        yield w
+
+
+@contextmanager
+def expected_warnings(matching):
+    """Context for use in testing to catch known warnings matching regexes
+    
+    Parameters
+    ----------
+    matching : list of strings or compiled regexes
+        Regexes for the desired warning to catch
+    Examples
+    --------
+    >>> from skimage import data, img_as_ubyte, img_as_float
+    >>> with expected_warnings(['precision loss']):
+    ...     d = img_as_ubyte(img_as_float(data.coins()))
+    Notes
+    -----
+    Uses `all_warnings` to ensure all warnings are raised.
+    Upon exiting, it checks the recorded warnings for the desired matching
+    pattern(s).  
+    Raises a ValueError if any match was not found or an unexpected
+    warning was raised.  
+    Allows for three types of behaviors: "and", "or", and "optional" matches. 
+    This is done to accomodate different build enviroments or loop conditions
+    that may produce different warnings.  The behaviors can be combined.
+    If you pass multiple patterns, you get an orderless "and", where all of the
+    warnings must be raised.
+    If you use the "|" operator in a pattern, you can catch one of several warnings.
+    Finally, you can use "|\A\Z" in a pattern to signify it as optional.
+    """
+    with all_warnings() as w:
+        # enter context
+        yield w
+        # exited user context, check the recorded warnings
+        remaining = [m for m in matching if not '\A\Z' in m.split('|')]
+        for warn in w:
+            found = False
+            for match in matching:
+                if re.search(match, str(warn.message)) is not None:
+                    found = True
+                    if match in remaining:
+                        remaining.remove(match)
+            if not found:
+                raise ValueError('Unexpected warning: %s' % str(warn.message))
+        if len(remaining) > 0:
+            msg = 'No warning raised matching:\n%s' % '\n'.join(remaining)
+            raise ValueError(msg)