ld31-space-diggers/node_modules/gulp-sourcemaps/README.md

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2014-12-07 20:57:49 +01:00
## gulp-sourcemaps [![NPM version][npm-image]][npm-url] [![build status][travis-image]][travis-url] [![Test coverage][coveralls-image]][coveralls-url]
### Usage
#### Inline maps
Inline maps are embedded in the source file.
Example:
```javascript
var gulp = require('gulp');
var plugin1 = require('gulp-plugin1');
var plugin2 = require('gulp-plugin2');
var sourcemaps = require('gulp-sourcemaps');
gulp.task('javascript', function() {
gulp.src('src/**/*.js')
.pipe(sourcemaps.init())
.pipe(plugin1())
.pipe(plugin2())
.pipe(sourcemaps.write())
.pipe(gulp.dest('dist'));
});
```
All plugins between `sourcemaps.init()` and `sourcemaps.write()` need to have support for `gulp-sourcemaps`. You can find a list of such plugins in the [wiki](https://github.com/floridoo/gulp-sourcemaps/wiki/Plugins-with-gulp-sourcemaps-support).
#### External source map files
To write external source map files, pass a path relative to the destination to `sourcemaps.write()`.
Example:
```javascript
var gulp = require('gulp');
var plugin1 = require('gulp-plugin1');
var plugin2 = require('gulp-plugin2');
var sourcemaps = require('gulp-sourcemaps');
gulp.task('javascript', function() {
gulp.src('src/**/*.js')
.pipe(sourcemaps.init())
.pipe(plugin1())
.pipe(plugin2())
.pipe(sourcemaps.write('../maps'))
.pipe(gulp.dest('dist'));
});
```
#### Load existing source maps
To load existing source maps, pass the option `loadMaps: true` to `sourcemaps.init()`.
Example:
```javascript
var gulp = require('gulp');
var plugin1 = require('gulp-plugin1');
var plugin2 = require('gulp-plugin2');
var sourcemaps = require('gulp-sourcemaps');
gulp.task('javascript', function() {
gulp.src('src/**/*.js')
.pipe(sourcemaps.init({loadMaps: true}))
.pipe(plugin1())
.pipe(plugin2())
.pipe(sourcemaps.write())
.pipe(gulp.dest('dist'));
});
```
### Init Options
- `loadMaps`
Set to true to load existing maps for source files. Supports the following:
- inline source maps
- source map files referenced by a `sourceMappingURL=` comment
- source map files with the same name (plus .map) in the same directory
- `debug`
Set this to `true` to output debug messages (e.g. about missing source content).
### Write Options
- `addComment`
By default a comment containing / referencing the source map is added. Set this to `false` to disable the comment (e.g. if you want to load the source maps by header).
Example:
```javascript
gulp.task('javascript', function() {
var stream = gulp.src('src/**/*.js')
.pipe(sourcemaps.init())
.pipe(plugin1())
.pipe(plugin2())
.pipe(sourcemaps.write('../maps', {addComment: false}))
.pipe(gulp.dest('dist'));
});
```
- `includeContent`
By default the source maps include the source code. Pass `false` to use the original files.
Including the content is the recommended way, because it "just works". When setting this to `false` you have to host the source files and set the correct `sourceRoot`.
- `sourceRoot`
Set the path where the source files are hosted (use this when `includeContent` is set to `false`). This is an URL (or subpath) relative to the source map, not a local file system path. If you have sources in different subpaths, an absolute path (from the domain root) pointing to the source file root is recommended, or define it with a function.
Example:
```javascript
gulp.task('javascript', function() {
var stream = gulp.src('src/**/*.js')
.pipe(sourcemaps.init())
.pipe(plugin1())
.pipe(plugin2())
.pipe(sourcemaps.write({includeContent: false, sourceRoot: '/src'}))
.pipe(gulp.dest('dist'));
});
```
Example (using a function):
```javascript
gulp.task('javascript', function() {
var stream = gulp.src('src/**/*.js')
.pipe(sourcemaps.init())
.pipe(plugin1())
.pipe(plugin2())
.pipe(sourcemaps.write({
includeContent: false,
sourceRoot: function(file) {
return '/src';
}
}))
.pipe(gulp.dest('dist'));
});
```
- `sourceMappingURLPrefix`
Specify a prefix to be prepended onto the source map URL when writing external source maps. Relative paths will have their leading dots stripped.
Example:
```javascript
gulp.task('javascript', function() {
var stream = gulp.src('src/**/*.js')
.pipe(sourcemaps.init())
.pipe(plugin1())
.pipe(plugin2())
.pipe(sourcemaps.write('../maps', {
sourceMappingURLPrefix: 'https://asset-host.example.com/assets'
}))
.pipe(gulp.dest('public/scripts'));
});
```
This will result in source mapping URL comment like `sourceMappingURL=https://asset-host.example.com/assets/maps/helloworld.js.map`.
- `debug`
Set this to `true` to output debug messages (e.g. about missing source content).
### Plugin developers only: How to add source map support to plugins
- Generate a source map for the transformation the plugin is applying
- **Important**: Make sure the paths in the generated source map (`file` and `sources`) are relative to `file.base` (e.g. use `file.relative`).
- Apply this source map to the vinyl `file`. E.g. by using [vinyl-sourcemaps-apply](https://github.com/floridoo/vinyl-sourcemaps-apply).
This combines the source map of this plugin with the source maps coming from plugins further up the chain.
- Add your plugin to the [wiki page](https://github.com/floridoo/gulp-sourcemaps/wiki/Plugins-with-gulp-sourcemaps-support)
#### Example:
```javascript
var through = require('through2');
var applySourceMap = require('vinyl-sourcemaps-apply');
var myTransform = require('myTransform');
module.exports = function(options) {
function transform(file, encoding, callback) {
// generate source maps if plugin source-map present
if (file.sourceMap) {
options.makeSourceMaps = true;
}
// do normal plugin logic
var result = myTransform(file.contents, options);
file.contents = new Buffer(result.code);
// apply source map to the chain
if (file.sourceMap) {
applySourceMap(file, result.map);
}
this.push(file);
callback();
}
return through.obj(transform);
};
```
[npm-image]: https://img.shields.io/npm/v/gulp-sourcemaps.svg?style=flat
[npm-url]: https://npmjs.org/package/gulp-sourcemaps
[travis-image]: https://img.shields.io/travis/floridoo/gulp-sourcemaps.svg?style=flat
[travis-url]: https://travis-ci.org/floridoo/gulp-sourcemaps
[coveralls-image]: https://img.shields.io/coveralls/floridoo/gulp-sourcemaps.svg?style=flat
[coveralls-url]: https://coveralls.io/r/floridoo/gulp-sourcemaps?branch=master