This plugin is checking for duplicate files (based on their name) in the stream and filter them or throw an error.
Install:
npm install gulp-dedupe --save-dev
Example:
var dedupe = require('gulp-dedupe');
...
.pipe(dedupe()) // Remove duplicates from previous tasks (if any).
.pipe(concat('bundle.css')) // For example, we need to concat the result without duplicates.
.pipe(gulp.dest('./build'));
dedupe(options) optionally accepts options object. The following options are
available:
error to emit an error in case of duplicate (false by default).
same to emit an error in case duplicates have different contents (true by
default).
diff to supply duplicates with different contents error from previous option
with actual diff (false by default).