jQuery — New Wave JavaScript
Meetings are currently held on the matrix.org platform.
Meeting minutes can be found at meetings.jquery.org.
Contribution Guides
In the spirit of open source software development, jQuery always encourages community code contribution. To help you get started and before you jump into writing code, be sure to read these important contribution guidelines thoroughly:
References to issues/PRs
GitHub issues/PRs are usually referenced via gh-NUMBER
, where NUMBER
is the numerical ID of the issue/PR. You can find such an issue/PR under https://github.com/jquery/jquery/issues/NUMBER
.
jQuery has used a different bug tracker - based on Trac - in the past, available under bugs.jquery.com. It is being kept in read only mode so that referring to past discussions is possible. When jQuery source references one of those issues, it uses the pattern trac-NUMBER
, where NUMBER
is the numerical ID of the issue. You can find such an issue under https://bugs.jquery.com/ticket/NUMBER
.
Environments in which to use jQuery
- Browser support
- jQuery also supports Node, browser extensions, and other non-browser environments.
What you need to build your own jQuery
To build jQuery, you need to have the latest Node.js/npm and git 1.7 or later. Earlier versions might work, but are not supported.
For Windows, you have to download and install git and Node.js.
macOS users should install Homebrew. Once Homebrew is installed, run brew install git
to install git,
and brew install node
to install Node.js.
Linux/BSD users should use their appropriate package managers to install git and Node.js, or build from source if you swing that way. Easy-peasy.
How to build your own jQuery
First, clone the jQuery git repo.
Then, enter the jquery directory, install dependencies, and run the build script:
cd jquery
npm install
npm run build
The built version of jQuery will be placed in the dist/
directory, along with a minified copy and associated map file.
Build all jQuery release files
To build all variants of jQuery, run the following command:
npm run build:all
This will create all of the variants that jQuery includes in a release, including jquery.js
, jquery.slim.js
, jquery.module.js
, and jquery.slim.module.js
along their associated minified files and sourcemaps.
jquery.module.js
and jquery.slim.module.js
are ECMAScript modules that export jQuery
and $
as named exports are placed in the dist-module/
directory rather than the dist/
directory.
Building a Custom jQuery
The build script can be used to create a custom version of jQuery that includes only the modules you need.
Any module may be excluded except for core
. When excluding selector
, it is not removed but replaced with a small wrapper around native querySelectorAll
(see below for more information).
Build Script Help
To see the full list of available options for the build script, run the following:
npm run build -- --help
Modules
To exclude a module, pass its path relative to the src
folder (without the .js
extension) to the --exclude
option. When using the --include
option, the default includes are dropped and a build is created with only those modules.
Some example modules that can be excluded or included are:
-
ajax: All AJAX functionality:
$.ajax()
,$.get()
,$.post()
,$.ajaxSetup()
,.load()
, transports, and ajax event shorthands such as.ajaxStart()
. -
ajax/xhr: The XMLHTTPRequest AJAX transport only.
-
ajax/script: The
<script>
AJAX transport only; used to retrieve scripts. -
ajax/jsonp: The JSONP AJAX transport only; depends on the ajax/script transport.
-
css: The
.css()
method. Also removes all modules depending on css (including effects, dimensions, and offset). -
css/showHide: Non-animated
.show()
,.hide()
and.toggle()
; can be excluded if you use classes or explicit.css()
calls to set thedisplay
property. Also removes the effects module. -
deprecated: Methods documented as deprecated but not yet removed.
-
dimensions: The
.width()
and.height()
methods, includinginner-
andouter-
variations. -
effects: The
.animate()
method and its shorthands such as.slideUp()
or.hide("slow")
. -
event: The
.on()
and.off()
methods and all event functionality. -
event/trigger: The
.trigger()
and.triggerHandler()
methods. -
offset: The
.offset()
,.position()
,.offsetParent()
,.scrollLeft()
, and.scrollTop()
methods. -
wrap: The
.wrap()
,.wrapAll()
,.wrapInner()
, and.unwrap()
methods. -
core/ready: Exclude the ready module if you place your scripts at the end of the body. Any ready callbacks bound with
jQuery()
will simply be called immediately. However,jQuery(document).ready()
will not be a function and.on("ready", ...)
or similar will not be triggered. -
deferred: Exclude jQuery.Deferred. This also excludes all modules that rely on Deferred, including ajax, effects, and queue, but replaces core/ready with core/ready-no-deferred.
-
exports/global: Exclude the attachment of global jQuery variables ($ and jQuery) to the window.
-
exports/amd: Exclude the AMD definition.
-
selector: The full jQuery selector engine. When this module is excluded, it is replaced with a rudimentary selector engine based on the browser's
querySelectorAll
method that does not support jQuery selector extensions or enhanced semantics. See the selector-native.js file for details.
Note: Excluding the full selector
module will also exclude all jQuery selector extensions (such as effects/animatedSelector
and css/hiddenVisibleSelectors
).
AMD name
You can set the module name for jQuery's AMD definition. By default, it is set to "jquery", which plays nicely with plugins and third-party libraries, but there may be cases where you'd like to change this. Pass it to the --amd
parameter:
npm run build -- --amd="custom-name"
Or, to define anonymously, leave the name blank.
npm run build -- --amd
File name and directory
The default name for the built jQuery file is jquery.js
; it is placed under the dist/
directory. It's possible to change the file name using --filename
and the directory using --dir
. --dir
is relative to the project root.
npm run build -- --slim --filename="jquery.slim.js" --dir="/tmp"
This would create a slim version of jQuery and place it under tmp/jquery.slim.js
.
ECMAScript Module (ESM) mode
By default, jQuery generates a regular script JavaScript file. You can also generate an ECMAScript module exporting jQuery
as the default export using the --esm
parameter:
npm run build -- --filename=jquery.module.js --esm
Factory mode
By default, jQuery depends on a global window
. For environments that don't have one, you can generate a factory build that exposes a function accepting window
as a parameter that you can provide externally (see README
of the published package for usage instructions). You can generate such a factory using the --factory
parameter:
npm run build -- --filename=jquery.factory.js --factory
This option can be mixed with others like --esm
or --slim
:
npm run build -- --filename=jquery.factory.slim.module.js --factory --esm --slim --dir="/dist-module"
Custom Build Examples
Create a custom build using npm run build
, listing the modules to be excluded. Excluding a top-level module also excludes its corresponding directory of modules.
Exclude all ajax functionality:
npm run build -- --exclude=ajax
Excluding css removes modules depending on CSS: effects, offset, dimensions.
npm run build -- --exclude=css
Exclude a bunch of modules (-e
is an alias for --exclude
):
npm run build -- -e ajax/jsonp -e css -e deprecated -e dimensions -e effects -e offset -e wrap
There is a special alias to generate a build with the same configuration as the official jQuery Slim build:
npm run build -- --filename=jquery.slim.js --slim
Or, to create the slim build as an esm module:
npm run build -- --filename=jquery.slim.module.js --slim --esm
Non-official custom builds are not regularly tested. Use them at your own risk.
Running the Unit Tests
Make sure you have the necessary dependencies:
npm install
Start npm start
to auto-build jQuery as you work:
npm start
Run the unit tests with a local server that supports PHP. Ensure that you run the site from the root directory, not the "test" directory. No database is required. Pre-configured php local servers are available for Windows and Mac. Here are some options:
- Windows: WAMP download
- Mac: MAMP download
- Linux: Setting up LAMP
- Mongoose (most platforms)
Essential Git
As the source code is handled by the Git version control system, it's useful to know some features used.
Cleaning
If you want to purge your working directory back to the status of upstream, the following commands can be used (remember everything you've worked on is gone after these):
git reset --hard upstream/main
git clean -fdx
Rebasing
For feature/topic branches, you should always use the --rebase
flag to git pull
, or if you are usually handling many temporary "to be in a github pull request" branches, run the following to automate this:
git config branch.autosetuprebase local
(see man git-config
for more information)
Handling merge conflicts
If you're getting merge conflicts when merging, instead of editing the conflicted files manually, you can use the feature
git mergetool
. Even though the default tool xxdiff
looks awful/old, it's rather useful.
The following are some commands that can be used there:
Ctrl + Alt + M
- automerge as much as possibleb
- jump to next merge conflicts
- change the order of the conflicted linesu
- undo a mergeleft mouse button
- mark a block to be the winnermiddle mouse button
- mark a line to be the winnerCtrl + S
- saveCtrl + Q
- quit
QUnit Reference
Test methods
expect( numAssertions );
stop();
start();
Note: QUnit's eventual addition of an argument to stop/start is ignored in this test suite so that start and stop can be passed as callbacks without worrying about their parameters.
Test assertions
ok( value, [message] );
equal( actual, expected, [message] );
notEqual( actual, expected, [message] );
deepEqual( actual, expected, [message] );
notDeepEqual( actual, expected, [message] );
strictEqual( actual, expected, [message] );
notStrictEqual( actual, expected, [message] );
throws( block, [expected], [message] );
Test Suite Convenience Methods Reference (See test/data/testinit.js)
Returns an array of elements with the given IDs
q( ... );
Example:
q("main", "foo", "bar");
=> [ div#main, span#foo, input#bar ]
Asserts that a selection matches the given IDs
t( testName, selector, [ "array", "of", "ids" ] );
Example:
t("Check for something", "//[a]", ["foo", "bar"]);
Fires a native DOM event without going through jQuery
fireNative( node, eventType )
Example:
fireNative( jQuery("#elem")[0], "click" );
Add random number to url to stop caching
url( "some/url" );
Example:
url("index.html");
=> "data/index.html?10538358428943"
url("mock.php?foo=bar");
=> "data/mock.php?foo=bar&10538358345554"
Run tests in an iframe
Some tests may require a document other than the standard test fixture, and these can be run in a separate iframe. The actual test code and assertions remain in jQuery's main test files; only the minimal test fixture markup and setup code should be placed in the iframe file.
testIframe( testName, fileName,
function testCallback(
assert, jQuery, window, document,
[ additional args ] ) {
...
} );
This loads a page, constructing a url with fileName "./data/" + fileName
.
The iframed page determines when the callback occurs in the test by
including the "/test/data/iframeTest.js" script and calling
startIframeTest( [ additional args ] )
when appropriate. Often this
will be after either document ready or window.onload
fires.
The testCallback
receives the QUnit assert
object created by testIframe
for this test, followed by the global jQuery
, window
, and document
from
the iframe. If the iframe code passes any arguments to startIframeTest
,
they follow the document
argument.
Questions?
If you have any questions, please feel free to ask on the Developing jQuery Core forum or in #jquery on libera.