15 lines
945 B
Text
15 lines
945 B
Text
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PyHamcrest is a framework for writing matcher objects, allowing you to
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declaratively define "match" rules. There are a number of situations where
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matchers are invaluable, such as UI validation, or data filtering, but it is in
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the area of writing flexible tests that matchers are most commonly used.
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When writing tests it is sometimes difficult to get the balance right between
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overspecifying the test (and making it brittle to changes), and not specifying
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enough (making the test less valuable since it continues to pass even when the
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thing being tested is broken). Having a tool that allows you to pick out
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precisely the aspect under test and describe the values it should have, to a
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controlled level of precision, helps greatly in writing tests that are "just
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right." Such tests fail when the behavior of the aspect under test deviates
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from the expected behavior, yet continue to pass when minor, unrelated changes
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to the behaviour are made.
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