Gulp TypeError: Arguments to path.join must be strings
问题 I have i problem with gulp-ruby-sass. When i try to run the watch task and change some .sass files it occurs error: TypeError: Arguments to path.join must be strings Here is my gulpfile.js var gulp = require('gulp'); var jade = require('gulp-jade'); var sass = require('gulp-ruby-sass'); var watch = require('gulp-watch'); gulp.task('sass', function() { return gulp.src('sass/*.sass') .pipe(sass()) .pipe(gulp.dest('./css')); }); gulp.task('watch', function() { gulp.watch('./sass/*.sass', ['sass'