Introduction
------------

This directory contains testsuites for CSS WG specifications, including ones
that do not strictly speaking define CSS features, e.g.,
[Geometry Interfaces](https://drafts.fxtf.org/geometry/).

The directories should be named like the specification's shortname, but without
any level suffix.

As the test harness relies on the largely undocumented old CSS build system,
this directory has a number of test requirements specific to it:

 * support files for a given test must live in an adjacent `support` directory;

 * tests must have a [`<link rel=help>`][spec-link] pointing to what they are
   testing;

 * for each spec so linked, test filenames must be unique; and

 * support and reference files must have unique filenames within the entire
   `css` directory.


vendor-imports/ Directory
-------------------------

vendor-imports/ is the remains of a legacy directory where third parties
historically imported their tests. These tests should be moved into the correct
directory under css/, see
[#8615](https://github.com/web-platform-tests/wpt/issues/8615). In the meantime,
feel free to fix any test bugs in the usual way.

Importing Old Branches
----------------------

Given an old branch in git based against the old csswg-test
repository, it can be moved over to the merged repo in one of two
ways:

 * (Recommended:) Rebasing on top of web-platform-tests: with the old
   branch checked out, run `git rebase -Xsubtree=css/ origin/master`
   (or similar, depending on the name of the upstream remote).

 * Merging to web-platform-tests: with web-platform-tests' master
   branch checked out, run `git merge -Xsubtree=css/ my_shiny_branch`
   (or similar, depending on the name of your branch).

If you have a branch/bookmark in Mercurial, the process is more
complicated:

 1. From the Mercurial repo, run `hg export --git -r 'outgoing()' >
    foo.patch`. This will export all the changeset shown in `hg log -r
    'outgoing()'`; it's recommended you check this is the right set of
    changesets before continuing!

 2. Move to the git repo, and create a new branch based on
    web-platform-tests' master; e.g., `git checkout -b hg-import
    origin/master` (or similar, depending on the name of the upstream
    remote).

 3. Download [hg-patch-to-git-patch][] and run `python2
    hg-patch-to-git-patch < foo.patch > bar.patch` (where `foo.patch`
    is the path to the `foo.patch` you exported above).

 4. Run `git am --directory=css/ < bar.patch`.


[harness]: https://test.csswg.org/harness/
[spec-link]: https://web-platform-tests.org/writing-tests/css-metadata.html#specification-links
[hg-patch-to-git-patch]: https://raw.githubusercontent.com/mozilla/moz-git-tools/master/hg-patch-to-git-patch