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TypeError: listener must be a function

See original GitHub issue

Recently my gulp task to build styles has started to fail with a very cryptic error message and I can’t seem to find any fix. This ran fine before, I can’t really say what has changed since then. I do however always seem to have to reinstall gulp-sass to get it to stop complaining about lib-sass bindings. My task looks like this:

gulp.task('sass', function() {
  gulp.src('./assets/**/*.scss')
    .pipe(sass().on('error', sass.logError))
    .pipe(gulp.dest('./dev'));
});

And the error I’m getting:

[14:52:06] TypeError: listener must be a function
    at TypeError (native)
    at Stream.addListener (events.js:142:11)
    at Gulp.<anonymous> (/Applications/MAMP/htdocs/<REDACTED>/<REDACTED>/gulpfile.js:38:18)
    at module.exports (/Applications/MAMP/htdocs/<REDACTED>/<REDACTED>/node_modules/gulp/node_modules/orchestrator/lib/runTask.js:34:7)
    at Gulp.Orchestrator._runTask (/Applications/MAMP/htdocs/<REDACTED>/<REDACTED>/node_modules/gulp/node_modules/orchestrator/index.js:273:3)
    at Gulp.Orchestrator._runStep (/Applications/MAMP/htdocs/<REDACTED>/<REDACTED>/node_modules/gulp/node_modules/orchestrator/index.js:214:10)
    at Gulp.Orchestrator.start (/Applications/MAMP/htdocs/<REDACTED>/<REDACTED>/node_modules/gulp/node_modules/orchestrator/index.js:134:8)
    at /Users/ianaw/.nvm/versions/node/v0.12.7/lib/node_modules/gulp/bin/gulp.js:129:20
    at process._tickCallback (node.js:355:11)
    at Function.Module.runMain (module.js:503:11)