This is the test suites from a number of W3C Working Groups, including the HTML Working Group, the Web Apps Working Group, the Device APIs Working Group, and the Web Apps Security Working Group.

The master branch is automatically synced to: http://w3c-test.org/web-platform-tests/master/. Likewise the CR branch (that matches the test suites used for the Candidate Recommendations of HTML5, Canvas 2D and Microdata) to: http://w3c-test.org/web-platform-tests/CR/.

Pull requests that have been checked are automatically mirrored to https://w3c-test.org/web-platform-tests/submissions/

Each top-level directory represents a W3C specification: the name matches the shortname used after the canonical address of the said specification under http://www.w3.org/TR/ .

For some of the specifications, the tree under the top-level directory represents the sections of the respective documents, using the section IDs for directory names, with a maximum of three levels deep.

So if you're looking for tests in HTML for "The History interface", they will be under html/browsers/history/the-history-interface/.

Various resources that tests depend on are in common, images, and fonts.

In order to function properly, tests need to be run from a web server that has testharness.js in /resources/.

If you're looking at a section of the specification and can't figure out where the directory is for it in the tree, just run: node tools/scripts/id2path.js your-id

In the vast majority of cases the only branch that you should need to care about is master.

There is another branch called CR. This is a strict subset of master that is limited to features that are found in the Candidate Recommendation version of the relevant specifications.

If you see other branches in the repository, you can generally safely ignore them. Please note that branches prefixed with temp/ are temporary branches and can get deleted at some point. So don't base any work off them unless you want to see your work destroyed.

Save the Web, Write Some Tests!

Absolutely everyone is welcome (and even encouraged) to contribute to test development, so long as you fulfill the contribution requirements detailed in the Contributing Guidelines. No test is too small or too simple, especially if it corresponds to something for which you've noted an interoperability bug in a browser.

The way to contribute is just as usual:

• fork this repository (and make sure you're still relatively in sync with it if you forked a while ago);
• create a branch for your changes, git checkout -b submission/your-name;
• make your changes;
• push that to your repo;
• and send in a pull request based on the above.

Please make your pull requests either to master or to a feature branch (but not to CR).

We can sometimes take a little while to go through pull requests because we have to go through all the tests and ensure that they match the specification correctly. But we look at all of them, and take everything that we can.

If you wish to contribute actively, you're very welcome to join the [email protected] mailing list (low traffic) by signing up to our mailing list.