64 lines
1.6 KiB
Plaintext
64 lines
1.6 KiB
Plaintext
== Why is this an issue?
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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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[source,python]
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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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== Resources
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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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ifdef::env-github,rspecator-view[]
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'''
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== Implementation Specification
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(visible only on this page)
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include::message.adoc[]
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include::highlighting.adoc[]
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'''
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== Comments And Links
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(visible only on this page)
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include::comments-and-links.adoc[]
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endif::env-github,rspecator-view[]
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