Only pass through changed files
No more wasting precious time on processing unchanged files.
By default it's only able to detect whether files in the stream changed. If you require something more advanced like knowing if imports/dependencies changed, create a custom comparator, or use another plugin.
$ npm install --save-dev gulp-changed
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const gulp = require('gulp');
const changed = require('gulp-changed');
const ngAnnotate = require('gulp-ng-annotate'); // Just as an example
const SRC = 'src/*.js';
const DEST = 'dist';
gulp.task('default', () =>
gulp.src(SRC)
.pipe(changed(DEST))
// `ngAnnotate` will only get the files that
// changed since the last time it was run
.pipe(ngAnnotate())
.pipe(gulp.dest(DEST))
);
Type: string
Function
Destination directory. Same as you put into gulp.dest()
.
This is needed to be able to compare the current files with the destination files.
Can also be a function returning a destination directory path.
Type: Object
Type: string
Default: process.cwd()
Working directory the folder is relative to.
Type: string
Extension of the destination files.
Useful if it differs from the original, like in the example below:
gulp.task('jade', () =>
gulp.src('src/**/*.jade')
.pipe(changed('app', {extension: '.html'}))
.pipe(jade())
.pipe(gulp.dest('app'))
);
Type: Function
Default: changed.compareLastModifiedTime
Function that determines whether the source file is different from the destination file.
changed.compareLastModifiedTime
changed.compareContents
changed.compareSha1Digest
(Deprecated)
gulp.task('jade', () =>
gulp.src('src/**/*.jade')
.pipe(changed('app', {hasChanged: changed.compareContents}))
.pipe(jade())
.pipe(gulp.dest('app'))
);
You can also supply a custom comparator function which will receive the following arguments and should return Promise
.
stream
(transform object stream) - Should be used to queuesourceFile
if it passes some comparisonsourceFile
(Vinyl file object)destPath
(string) - Destination forsourceFile
as an absolute path
Type: Function
Function to transform the path to the destination file. Should return the absolute path to the (renamed) destination file.
Useful if you rename your file later on, like in the below example:
gulp.task('marked', () =>
gulp.src('src/content/about.md')
.pipe(changed('dist', {transformPath: newPath => path.join(path.dirname(newPath), path.basename(newPath, '.md'), 'index.html')}))
.pipe(marked())
.pipe(rename(newPath => path.join(path.dirname(newPath), path.basename(newPath, '.md'), 'index.html'))))
.pipe(gulp.dest('dist'))
);
If you're looking to process source files in-place without any build output (formatting, linting, etc), have a look at gulp-changed-in-place.
MIT © Sindre Sorhus