Fontspector is a command-line tool for checking the quality of font projects. It is a Rust port of fontbakery.
Fontspector is made up of multiple crates:
fontbakery-bridge: Allows Python fontbakery checks to run inside fontspectorfontspector-checkapi: Defines the API and utility functions for check implementationsfontspector-checkhelper: Procedural macros to facilitate check implementationsfontspector-cli: The main fontspector executablefontspector-py: A Python module exposing fontspector (for which see below)fontspector-web: A WASM implementation of fontspector (for which see below)profile-testplugin: An example of a runtime-loadable test profileprofile-googlefonts,profile-opentype,profile-universal: Built in profiles and their check implementationsprofile-microsoft,profile-adobe, ...: Additional profiles which are loaded at runtime (see below)
You have two options for running the CLI tool - you can download our binaries, or you can compile your own.
- Official release binaries are available from the GitHub releases page.
- You can build the latest release from source with
cargo install fontspector. (If you don't have a Rust compiler installed, you can usebrew install rustupon macOS Homebrew or rustup to install one.) - You can build the bleeding-edge version with
cargo install git+https://github.com/fonttools/fontspector/
On macOS you'll need to pre-install the protobuf.dev package, such as with Homebrew like this:
brew install protobuf cargo build --release; ./target/release/fontspector ~/font.ttf;
The single fontspector binary contains all the built-in checks, profiles, and HTML/Markdown templates. As mentioned below, some profiles require additional plugin binaries.
By default, fontspector CLI is built without Python support. If you want to run
fontbakery checks inside fontspector, build with cargo build --release --features python. You can then use the --use-python flag at runtime to cause checks registered with Fontbakery to be run in Fontspector if no Rust implementation is available.
Fontspector also has a WASM-based web version at https://fonttools.github.io/fontspector/
It is built and deployed from Github Actions, but should you need to rebuild this manually for development, run:
cd fontspector-web
wasm-pack build
cd www; npm install; npm run build
The results appear in ../docs/.
We export the Fontspector check runner to a Python module, and then use
pytest to run (a modified version of) the fontbakery test suite. To
do this:
pip3 install -U maturin
cd fontspector-py
python3 -m venv venv ; . venv/bin/activate
pip install maturin
maturin develop
pytest
Some profiles such as the Microsoft profile require additional tests in Rust
to be registered with Fontspector. This is done through plugins, which are
dynamic libraries containing Rust code which get loaded at runtime. The easiest
way to build these profiles is to use cargo-cp-artifact, a Javascript utility.
To do this:
npm install
rpm run build-microsoft # build-adobe, build-test...
This will produce a file called microsoft.fontspectorplugin; to use this, run
fontspector \
--plugins microsoft.fontspectorplugin \ # This loads the code
--profile microsoft \ # This uses the profile defined in the plugin
MyFont.ttf