Summary: Yoga may be built with a high warning level. This is helpful in letting Yoga be used in more places, and finding defects. We currently set these in the internal BUCK build, the CMake reference build, and the Yoga Standalone (not RN) CocoaPods build. Yoga's reference CMake build and spec are consumed today by users of Yoga, instead of just Yoga developers. Here, it makes more sense to avoid anything that could break compiler-to-compiler compatibility. We default these to a less intense (`-Wall -Werror`). I kept `/W4`, for pragmatic reasons, and since it is relatively standard for MSVC. We continue to build with strict flags on Buck build on Clang. Fixes https://github.com/facebook/yoga/issues/1590 Differential Revision: D54735661
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 If the version is out of date, please create an issue or pull request on the vcpkg repository.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).