Summary: Pull Request resolved: https://github.com/facebook/yoga/pull/1593 X-link: https://github.com/facebook/react-native/pull/43417 There was a bug where we did not position absolute nodes correctly if the static node had a different main/cross axis from the containing node. This fixes that. The change is somewhat complicated unfortunately but I tried to add sufficient comments to explain what is happening Reviewed By: NickGerleman Differential Revision: D54703955 fbshipit-source-id: 096c643f61d4f9bb3ee6278d675ebd69b57350d7
Yoga

Yoga is an embeddable and performant flexbox layout engine with bindings for multiple languages.
Building
Yoga's main implementation targets C++ 20 with accompanying build logic in CMake. A wrapper is provided to build the main library and run unit tests.
./unit_tests <Debug|Release>
While not required, this script will use ninja if it is installed for faster builds.
Yoga is additionally part of the vcpkg collection of ports maintained by Microsoft and community contributors. If the version is out of date, please create an issue or pull request on the vcpkg repository.
Adding Tests
Many of Yoga's tests are automatically generated, using HTML fixtures describing node structure. These are rendered in Chrome to generate an expected layout result for the tree. New fixtures can be added to gentest/fixtures
.
<div id="my_test" style="width: 100px; height: 100px; align-items: center;">
<div style="width: 50px; height: 50px;"></div>
</div>
To generate new tests from added fixtures:
- Ensure you have yarn classic installed.
- Run
yarn install
to install dependencies for the test generator. - Run
yarn gentest
in theyoga
directory.
Debugging
Yoga provides a VSCode "launch.json" configuration which allows debugging unit tests. Simply add your breakpoints, and run "Debug C++ Unit tests (lldb)" (or "Debug C++ Unit tests (vsdbg)" on Windows).