44 lines
1.2 KiB
Plaintext
44 lines
1.2 KiB
Plaintext
Checking if a variable or parameter is ``++None++`` should only be done when you expect that it can be ``++None++``. Doing so when the variable is always None or never None is confusing at best. At worse, there is a bug and the variable is not updated properly.
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This rule raises an issue when expressions ``++X is None++``, ``++X is not None++``, ``++X == None++`` or ``++X != None++`` are constant, i.e. ``++X++`` is always None or never None.
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== Noncompliant Code Example
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----
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mynone = None
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result = mynone is None: # Noncompliant. Always True.
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if mynone == None: # Noncompliant. Always True.
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pass
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if mynone is not None: # Noncompliant. Always False.
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pass
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if mynone == None: # Noncompliant. Always False.
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pass
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myint = 42
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result = myint is None: # Noncompliant. Always False.
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if myint == None: # Noncompliant. Always False.
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pass
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if myint is not None: # Noncompliant. Always True.
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pass
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if myint == None: # Noncompliant. Always True.
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pass
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----
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:link-with-uscores1: https://docs.python.org/3/reference/datamodel.html#object.__eq__
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== See
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* Python documentation - https://docs.python.org/3/reference/expressions.html#is-not[Identity comparisons]
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* Python documentation - {link-with-uscores1}[``++__eq__++`` operator]
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