Silence JSHint when a specific

Question

Silence JSHint when a specific

Consider the following standard Express function:

if (app.get('env') === 'development') {
    app.use(function (err, req, res, next) {
        res.status(err.status || 500);
        res.render('error', {
            message: err.message,
            error: err
        });
    });
}

The following warning is displayed:

'next' is defined but never used. - W098

I know I can disable all warnings, but that's not what I want. What I need is to silence JSHint only for a specific parameter ('next' in the snippet above.)

I haven't seen any clear answers to this seemingly common issue. Any ideas?

Thanks!

node.js
express
jshint

Answer 1

Yes, this is possible!

If you are using the default setup of JSHint, the accepted answer on this thread is your answer too: Is there a way to suppress JSHint warning for one given line? It shows how to use comments to conditionally ignore specific errors/warnings from being thrown in JSHint.

If you are using a build tool like Gulp or Grunt, you can add this to your options in your plugin's task configuration. For example, with Grunt: See section "Ignoring specific warnings" on https://github.com/gruntjs/grunt-contrib-jshint/blob/master/README.md.

Hope this helps!

Answer 2

In this case you can do something like below

if (app.get('env') === 'development') {
    app.use(function (err, req, res, next) {
        /*jshint unused: vars*/
        var foo;

        res.status(err.status || 500);
        res.render('error', {
            message: err.message,
            error: err
        });
    });
}

Now jshint will not cry about next, though it will still warn about foo being defined but not used.

Importantly, This suppression will be bound to scope of the function.