gulp-dependencies-changed

gulp-dependencies-changed
=========================

Smart incremental building by dependency analysis.

Installation
------------

``shell
npm install --save-dev gulp-dependencies-changed
`


Usage
-----

`javascript
var less = require('gulp-less');
var changed = require('gulp-dependencies-changed');
var Path = require('path');
var rename = require('rename');

gulp.task('less', function() {
return gulp.src('./less/*/.less')
// Analyze dependencies for less. Pass through
// only files that its depending files are changed.
.pipe(changed({
matcher: /@import ['"]?([^'"]+)['"]?;/g,
dest: function(srcRelPath, srcBasePath) {
// It should return dest file path.
return rename(srcPath, function(fileObj) {
return {
dirname: Path.join('public/css' + fileObj.dirname)
extname: 'css',
};
});
},
}))
.pipe(less())
.pipe(gulp.dest('./public/css'));
});
`


API
---


$3

Only pass through dependent files that depending to changed files


#### options
##### matcher

Type: RegExp

This RegExp MUST include only a capturing group and SHOULD be global match.
The result of the match will be given to a pathResolver.


##### dest

Type: function(string, string): string

This function take an argument (a relative file path and the base path).
The source file path is exactly equivalent to path.relative(vinylFile.path, vinylFile.base).
It SHOULD return the file path for the dest file path.
The return value is used as a target of comparison.

You can easily rename by using rename.


##### pathResolver

Type: function(string, string): string

Default: changed.relativeResolver

This function take 2 arguments (a dependent file path, the depended file path captured by matcher) and MUST return a file path for the depending file.
If omitted, it takes a related file path from the dependent file.

If file extensions is omitted, you can complement the file extensions by the function.


##### comparator

Type: function(VinylFile, VinylFile): boolean

Default: changed.compareByMtime

This function take 2 arguments (a depending file and the dependent file) and it MUST return true when the depending is newer than the dependent file.
If omitted, it compare by the both mtime.


##### debug

Type: boolean

Default: false`

Print debug messages when it is truthy.

License
-------

MIT