[New Rule] Reduce conditional expressions to boolean expressions about flake8-simplify HOT 6 CLOSED

b if a else a is not equivalent to b or a.

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This would be pretty easy to check and implement:

IfExp(
                test=Name(id='a', ctx=Load()),
                body=Name(id='a', ctx=Load()),
                orelse=Name(id='b', ctx=Load()),
            ),

However, I'm uncertain of I would prefer the left or the right expression. Give me a couple of days to think about it. The right expression is shorter, but the left expression seems clearer to me.

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The second one I would rather convert to

b if a else a -> b or a. It might need less evaluation.

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I've just created the following expression tables with

abs = [("a", ""), ("", "b"), ("a", "b"), ("", 0)]
for a, b in abs:
    print(b if a else a)

Table for a if a else b and a or b:

Table for b if a else a and a and b:

Table for b or a:

Table for b and a:

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@SpecLad You're completely right. They don't even have a single element in common 😅

This example helped me to make my mind up about this rule. Although it easy to reason which input gives which output, I do need to think about it. I find the boolean expressions a or b / a and b / b or a / b and a harder to reason about than their ternary expression equivalents.

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As the ternary expressions (a if a else b) are easier for me to understand than the logical expressions (a or b), I will not implement this rule.

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