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"no-unused-vars" reports only the last function parameter

See original GitHub issue

With the following code:

const func = (req, res, next) => {};

only next is reported with the rule no-unused-vars.

This would not be an big issue but this actually triggers another bigger issue.

With the following code:

const func = (req, res, _next) => {};

and the following configuration:

"no-unused-vars": [ 2, { "argsIgnorePattern": "^_" }]

nothing is reported at all ! Which is IMO more serious.

Issue Analytics

State:
Created 7 years ago
Comments:8 (8 by maintainers)

Top GitHub Comments

1reaction

nzakascommented, Sep 13, 2016

Logistics: Use both “bug” and “enhancement” labels if it’s a confirmed bug and the fix would result in more warnings being reported.

1reaction

kaicataldocommented, Sep 13, 2016

@platinumazure Thanks for clarifying - that makes sense! I agree that an enhancement/bug fix for this would be great:

In the second example, ignoring a parameter isn’t the same as using it (or at least shouldn’t be), so I wouldn’t want req and res to be passed over in that case either.

I’m 👍 for @mysticatea’s suggestion to alter the "after-used" option to warn about the last parameter that isn’t ignored (rather than simply the last parameter).