A Gulp plugin for passing through only those source files that are newer than corresponding destination files.
npm install gulp-newer --save-dev
The default task in the example below sets up a watch that minifies images on changes. Piping the source files to newer
before imagemin
ensures that only those images that have changed are minified. The newer
plugin is configured with the directory path for minified images.
var gulp = require('gulp');
var newer = require('gulp-newer');
var imagemin = require('gulp-imagemin');
var imgSrc = 'src/img/**';
var imgDest = 'build/img';
// Minify any new images
gulp.task('images', function() {
// Add the newer pipe to pass through newer images only
return gulp.src(imgSrc)
.pipe(newer(imgDest))
.pipe(imagemin())
.pipe(gulp.dest(imgDest));
});
gulp.task('default', function() {
gulp.watch(imgSrc, ['images']);
});
Plugins like gulp-concat
take many source files and generate a single destination file. In this case, the newer
stream will pass through all source files if any one of them is newer than the destination file. The newer
plugin is configured with the destination file path.
var gulp = require('gulp');
var newer = require('gulp-newer');
var concat = require('gulp-concat');
// Concatenate all if any are newer
gulp.task('concat', function() {
// Add the newer pipe to pass through all sources if any are newer
return gulp.src('lib/*.js')
.pipe(newer('dist/all.js'))
.pipe(concat('all.js'))
.pipe(gulp.dest('dist'));
});
- dest -
string
Path to destination directory or file.
- options.dest -
string
As above, required. - options.ext -
string
Source files will be matched to destination files with the provided extension (e.g. '.css'). - options.map -
function
Map relative source paths to relative destination paths (e.g.function(relativePath) { return relativePath + '.bak'; }
) - options.extra -
string
orarray
An extra file, file glob, or list of extra files and/or globs, to check for updated time stamp(s). If any of these files are newer than the destination files, then all source files will be passed into the stream.
Create a transform stream that passes through files whose modification time is more recent than the corresponding destination file's modification time.
If dest
is a directory path, the newer
stream will check for files in the destination directory with the same relative path as source files. Source files that have been modified more recently than the resolved destination file will be passed through. If the dest
directory or resolved destination file does not exist, all source files will be passed through.
If dest
is a file path, the newer
stream will pass through all files if any one of them has been modified more recently than the destination file. If the dest
file does not exist, all source files will be passed through.