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Empty and Implicit Returns cause resiliency issues.

This code insight Counts one violation each time a function has at least one significant return (expression different from nothing, none or false) and in the same time :

•  at least one empty return OR
• an implicit return in place of the last statement.

bad def foo(x): if x >= 0: return math.sqrt(x) # <--- implicit return here def bar(x): if x < 0: return # <---- empty return here return math.sqrt(x) good def foo(x): if x >= 0: return math.sqrt(x) else: return Nonedef bar(x): if x < 0: return None return math.sqrt(x)

Why you should care

Be consistent in return statements. Either all return statements in a function should return an expression, or none of them should. If any return statement returns an expression, any return statements where no value is returned should explicitly state this as return None , and an explicit return statement should be present at the end of the function (if reachable).

Business Impacts

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CAST recommendations

References

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