freeCodeCamp/bower_components/jsdom/README.md

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# jsdom
A JavaScript implementation of the W3C DOM.
## Install
```bash
$ npm install jsdom
```
If this gives you trouble with errors about installing Contextify, especially on Windows, see [below](#contextify).
## Human contact
see: [mailing list](http://groups.google.com/group/jsdom)
## Easymode
Bootstrapping a DOM is generally a difficult process involving many error prone steps. We didn't want jsdom to fall into the same trap and that is why a new method, `jsdom.env()`, has been added in jsdom 0.2.0 which should make everyone's lives easier.
You can use it with a URL
```js
// Count all of the links from the Node.js build page
var jsdom = require("jsdom");
jsdom.env(
"http://nodejs.org/dist/",
["http://code.jquery.com/jquery.js"],
function (errors, window) {
console.log("there have been", window.$("a").length, "nodejs releases!");
}
);
```
or with raw HTML
```js
// Run some jQuery on a html fragment
var jsdom = require("jsdom");
jsdom.env(
'<p><a class="the-link" href="https://github.com/tmpvar/jsdom">jsdom\'s Homepage</a></p>',
["http://code.jquery.com/jquery.js"],
function (errors, window) {
console.log("contents of a.the-link:", window.$("a.the-link").text());
}
);
```
or with a configuration object
```js
// Print all of the news items on hackernews
var jsdom = require("jsdom");
jsdom.env({
url: "http://news.ycombinator.com/",
scripts: ["http://code.jquery.com/jquery.js"],
done: function (errors, window) {
var $ = window.$;
console.log("HN Links");
$("td.title:not(:last) a").each(function() {
console.log(" -", $(this).text());
});
}
});
```
or with raw JavaScript source
```js
// Print all of the news items on hackernews
var jsdom = require("jsdom");
var fs = require("fs");
var jquery = fs.readFileSync("./jquery.js", "utf-8");
jsdom.env({
url: "http://news.ycombinator.com/",
src: [jquery],
done: function (errors, window) {
var $ = window.$;
console.log("HN Links");
$("td.title:not(:last) a").each(function () {
console.log(" -", $(this).text());
});
}
});
```
### How it works
`jsdom.env` is built for ease of use, which is rare in the world of the DOM! Since the web has some absolutely horrible JavaScript on it, as of jsdom 0.2.0 `jsdom.env` will not process external resources (scripts, images, etc). If you want to process the JavaScript use one of the methods below (`jsdom.jsdom` or `jsdom.jQueryify`)
```js
jsdom.env(string, [scripts], [config], callback);
```
The arguments are:
- `string`: may be a URL, file name, or HTML fragment
- `scripts`: a string or array of strings, containing file names or URLs that will be inserted as `<script>` tags
- `config`: see below
- `callback`: takes two arguments
- `error`: either an `Error` object if something failed initializing the window, or an array of error messages from the DOM if there were script errors
- `window`: a brand new `window`
_Example:_
```js
jsdom.env(html, function (errors, window) {
// free memory associated with the window
window.close();
});
```
If you would like to specify a configuration object only:
```js
jsdom.env(config);
```
- `config.html`: a HTML fragment
- `config.file`: a file which jsdom will load HTML from; the resulting window's `location.href` will be a `file://` URL.
- `config.url`: sets the resulting window's `location.href`; if `config.html` and `config.file` are not provided, jsdom will load HTML from this URL.
- `config.scripts`: see `scripts` above.
- `config.src`: an array of JavaScript strings that will be evaluated against the resulting document. Similar to `scripts`, but it accepts JavaScript instead of paths/URLs.
- `config.jar`: a custom cookie jar, if desired; see [mikeal/request](https://github.com/mikeal/request) documentation.
- `config.done`: see `callback` above.
- `config.document`:
- `referrer`: the new document will have this referrer.
- `cookie`: manually set a cookie value, e.g. `'key=value; expires=Wed, Sep 21 2011 12:00:00 GMT; path=/'`.
- `cookieDomain`: a cookie domain for the manually set cookie; defaults to `127.0.0.1`.
- `config.features` : see `Flexibility` section below. **Note**: the default feature set for jsdom.env does _not_ include fetching remote JavaScript and executing it. This is something that you will need to **carefully** enable yourself.
Note that `config.done` is required, as is one of `config.html`, `config.file`, or `config.url`.
## For the hardcore
If you want to spawn a document/window and specify all sorts of options this is the section for you. This section covers the `jsdom.jsdom` method:
```js
var jsdom = require("jsdom").jsdom;
var doc = jsdom(markup, level, options);
var window = doc.parentWindow;
```
- `markup` is an HTML/XML document to be parsed. You can also pass `null` or an undefined value to get a basic document with empty `<head>` and `<body>` tags. Document fragments are also supported (including `""`), and will behave as sanely as possible (e.g. the resulting document will lack the `head`, `body` and `documentElement` properties if the corresponding elements aren't included).
- `level` is `null` (which means level3) by default, but you can pass another level if you'd like.
```js
var jsdom = require("jsdom");
var doc = jsdom.jsdom("<html><body></body></html>", jsdom.level(1, "core"));
```
- `options` See the explanation of the `config` object above.
### Flexibility
One of the goals of jsdom is to be as minimal and light as possible. This section details how someone can change the behavior of `Document`s on the fly. These features are baked into the `DOMImplementation` that every `Document` has, and may be tweaked in two ways:
1. When you create a new `Document` using the jsdom builder (`require("jsdom").jsdom()`)
```js
var jsdom = require("jsdom").jsdom;
var doc = jsdom("<html><body></body></html>", null, {
features: {
FetchExternalResources : ["img"]
}
});
```
Do note, that this will only affect the document that is currently being created. All other documents will use the defaults specified below (see: Default Features).
2. Before creating any documents, you can modify the defaults for all future documents:
```js
require("jsdom").defaultDocumentFeatures = {
FetchExternalResources: ["script"],
ProcessExternalResources: false
};
```
#### Default Features
Default features are extremely important for jsdom as they lower the configuration requirement and present developers a set of consistent default behaviors. The following sections detail the available features, their defaults, and the values that jsdom uses.
`FetchExternalResources`
- _Default_: `["script"]`
- _Allowed_: `["script", "img", "css", "frame", "iframe", "link"]` or `false`
Enables/disables fetching files over the file system/HTTP.
`ProcessExternalResources`
- _Default_: `["script"]`
- _Allowed_: `["script"]` or `false`
Disabling this will disable script execution (currently only JavaScript).
`SkipExternalResources`
- _Default_: `false`
- _Allowed_: `/url to be skipped/` or `false`
- _Example_: `/http:\/\/example.org/js/bad\.js/`
Do not download and process resources with url matching a regular expression.
### Canvas
jsdom includes support for using the [canvas](https://npmjs.org/package/canvas) package to extend any `<canvas>` elements with the canvas API. To make this work, you need to include canvas as a dependency in your project, as a peer of jsdom. If jsdom can find the canvas package, it will use it, but if it's not present, then `<canvas>` elements will behave like `<div>`s.
## More Examples
### Creating a document
```js
var jsdom = require("jsdom");
var doc = new (jsdom.level(1, "core").Document)();
console.log(doc.nodeName); // outputs: #document
```
### Creating a browser-like BOM/DOM/Window
```js
var jsdom = require("jsdom").jsdom;
var document = jsdom("<html><head></head><body>hello world</body></html>");
var window = document.parentWindow;
console.log(window.document.innerHTML);
// output: "<html><head></head><body>hello world</body></html>"
console.log(window.innerWidth);
// output: 1024
console.log(typeof window.document.getElementsByClassName);
// outputs: function
```
### jQueryify
```js
var jsdom = require("jsdom");
var window = jsdom.jsdom().parentWindow;
jsdom.jQueryify(window, "http://code.jquery.com/jquery.js", function () {
window.$("body").append('<div class="testing">Hello World, It works</div>');
console.log(window.$(".testing").text());
});
```
### Passing objects to scripts inside the page
```js
var jsdom = require("jsdom").jsdom;
var window = jsdom().parentWindow;
window.__myObject = { foo: "bar" };
var scriptEl = window.document.createElement("script");
scriptEl.src = "anotherScript.js";
window.document.body.appendChild(scriptEl);
// anotherScript.js will have the ability to read `window.__myObject`, even
// though it originated in Node!
```
## Test Compliance:
```
level1/core 535/535 100%
level1/html 238/238 100%
level1/svg 527/527 100%
level2/core 287/287 100%
level2/html 717/717 100%
level2/style 15/15 100%
level2/extra 4/4 100%
level2/events 24/24 100%
level3/xpath 93/93 100%
whatwg/attributes 10/10 100%
window/index 8/8 100%
window/history 5/5 100%
window/script 10/10 100%
window/console 2/2 100%
window/frame 17/17 100%
sizzle/index 14/14 100%
jsdom/index 84/84 100%
jsdom/parsing 11/11 100%
jsdom/env 25/25 100%
jsdom/utils 11/11 100%
jsonp/jsonp 1/1 100%
browser/css 1/1 100%
browser/index 34/34 100%
------------------------------------------
TOTALS: 0/2673 failed; 100% success
```
### Running the tests
First you'll want to `npm install`. To run all the tests, use `npm test`, which just calls `node test/runner`.
Using `test/runner` directly, you can slice and dice which tests your want to run from different levels. Usage is as follows:
```
test/runner --help
Run the jsdom test suite
Options:
-s, --suites suites that you want to run. ie: -s level1/core,1/html,html [string]
-f, --fail-fast stop on the first failed test
-h, --help show the help
-t, --tests choose the test cases to run. ie: -t jquery
```
## Contextify
[Contextify](https://npmjs.org/package/contextify) is a dependency of jsdom, used for running `<script>` tags within the
page. In other words, it allows jsdom, which is run in Node.js, to run strings of JavaScript in an isolated environment
that pretends to be a browser environment instead of a server. You can see how this is an important feature.
Unfortunately, doing this kind of magic requires C++. And in Node.js, using C++ from JavaScript means using "native
modules." Native modules are compiled at installation time so that they work precisely for your machine; that is, you
don't download a contextify binary from npm, but instead build one locally after downloading the source from npm.
Unfortunately, getting C++ compiled within npm's installation system can be tricky, especially for Windows users. Thus,
one of the most common problems with jsdom is trying to use it without the proper compilation tools installed.
Here's what you need to compile Contextify, and thus to install jsdom:
### Windows
* A recent copy of the *x86* version of [Node.js for Windows](http://nodejs.org/download/), *not* the x64 version.
* A copy of [Visual C++ 2010 Express](http://www.microsoft.com/visualstudio/eng/downloads#d-2010-express).
* A copy of [Python 2.7](http://www.python.org/download/), installed in the default location of `C:\Python27`.
There are some slight modifications to this that can work; for example full versions of Visual Studio usually work, and
sometimes you can even get an x64 version of Node.js working too. But it's tricky, so start with the basics!
### Mac
* XCode needs to be installed
* "Command line tools for XCode" need to be installed
* Launch XCode once to accept the license, etc. and ensure it's properly installed
### Linux
You'll need various build tools installed, like `make`, Python 2.7, and a compiler toolchain. How to install these will
be specific to your distro, if you don't already have them.