The fontc_crater crate (named after rust-lang/crater) is a tool for
performing compilation and related actions across a large number of source
fonts.
Discovery of font sources is managed by a separate tool,
google-fonts-sources; this tool checks out the
github.com/google/fonts repository and looks for fonts with
known source repos. You can use the --fonts-repo argument to pass the path to
an existing checkout of this repository, which saves time.
Once sources are identified, they are checked out into a cache directory, where they can be reused between runs.
This tool is mainly used in CI. In that case, the execution is managed by a
script in the fontc_crater repo and results are posted to
github pages.
To run in CI mode locally to play with the html output:
When run in CI, we want to ensure that we have complete control over the set of
python pacakges we are comparing against; to ensure this we use pip-compile
(part of pip-tools) to generate a pinned requirements.txt from a
requirements.in file in the root resources/scripts directory.
To update the set of python packages in use, you need to update this file:
# Make sure you have pip-tools
$ python -m pip install pip-tools
# Rebuild the file
# Remove it to force a complete update rather than minimal
$ rm -f resources/scripts/requirements.txt && pip-compile resources/scripts/requirements.in
# Commit updated file# clone [email protected]:googlefonts/fontc_crater.git somewhere, we'll assume at ../fontc_crater
# CI currently has it's own format for the repo list, use the file from ^
$ cargo run --release -p=fontc_crater -- ci ../fontc_crater/gf-repos-2024-09-23.json -o ../fontc_crater/results/ --html-only
# Review ../fontc_crater/results/index.html (NOT ../fontc_crater/index.html)