Gulp write file if none exist -

how can make gulp write file if there no existing file.

the bellow solution works gulp 4.0 in alpha.

// when gulp 4.0 releases .pipe(gulp.dest(conf.plugscss.dist, {overwrite: false})) 

there no exact equivalent in gulp 3.x, can use gulp-changed achieve same thing.

gulp-changed used write files have changed since last time written destination folder. can provide custom haschanged function. in case can write function nothing check if file exists using fs.stat():

var gulp = require('gulp'); var changed = require('gulp-changed'); var fs = require('fs');  function compareexistence(stream, cb, sourcefile, targetpath) {   fs.stat(targetpath, function(err, stats) {     if (err) {        stream.push(sourcefile);     }     cb();   }); }  gulp.task('default', function() {   return gulp.src(/*...*/)     .pipe(changed(conf.plugscss.dist, {haschanged: compareexistence}))     .pipe(gulp.dest(conf.plugscss.dist)); });