39 lines
1.1 KiB
Plaintext
39 lines
1.1 KiB
Plaintext
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Asserting deprecation and other warnings.
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=====================================================
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The recwarn function argument
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------------------------------------
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You can use the ``recwarn`` funcarg to assert that code triggers
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warnings through the Python warnings system. Here is a simple
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self-contained test::
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# content of test_recwarn.py
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def test_hello(recwarn):
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from warnings import warn
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warn("hello", DeprecationWarning)
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w = recwarn.pop(DeprecationWarning)
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assert issubclass(w.category, DeprecationWarning)
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assert 'hello' in str(w.message)
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assert w.filename
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assert w.lineno
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The ``recwarn`` function argument provides these methods:
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* ``pop(category=None)``: return last warning matching the category.
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* ``clear()``: clear list of warnings
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Ensuring a function triggers a deprecation warning
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-------------------------------------------------------
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You can also call a global helper for checking
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that a certain function call triggers a Deprecation
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warning::
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import pytest
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def test_global():
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pytest.deprecated_call(myfunction, 17)
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