I'm trying to work with this package here.

In my case, I want to show the progress bar while processing an indefinite number of files in the gulpfile. Like this:

gulp.task('styles', () => {
    return gulp.src([
            './dev/css/**/*.css',
            './dev/scss/**/*.scss',
        ])
        .pipe(sourcemaps.init())
        .pipe(debug(debugVars))
        .pipe(sass().on('error', sass.logError))
        .pipe(concat('styles.min.css'))
        .pipe(sourcemaps.write('.'))
        .pipe(gulp.dest('./public/deploy/css'))
})

How would I pass the files into progressStream for correct file size calculation and progress percentage?