Returning undefined triggers no-return-assign

• ESLint Version: 5.5.0
• Node Version: 10.6.0
• npm Version: 6.4.1

Default configuration; () => void (a = 1) triggers the no-return-assign rule even though it’s returning undefined.

[ljharb]

(to clarify, i don’t think this is a bug - the rules docs have the title of “Disallow Assignment in return Statement” - it’s in no way about the return value or the result of the assignment, and the description points out that the motivation is to catch the bug of doing = when you meant to do == or ===.

Because of this ambiguity, it’s considered a best practice to not use assignment in return statements.

There should be no exception here for void (imo there shouldn’t be one for parens either). At the worst, void could be under another option (like except-parens) but I don’t think there’s value in that versus the added rule complexity.

[ljharb]

The rule isn’t warning about returning the result of an assignment - it’s warning about having an assignment expression inside a return statement. Adding void doesn’t change that.