Rust ICU data loader library

Introduction

This directory contains the Rust bindings for the ICU data loader library. The library is made available through a low-level binding crate icu_data-sys and the higher-level API in icu_data.

Usage tips

The unit tests in icu_data show how one can use the library. There is only one object, Loader made available. The developer's task is to instantiate a Loader any time they want to have the system load ICU data, and keep the Loader in scope until data are no longer needed.

The underlying machinery will make sure that the ICU data are loaded before first use, and that they are unloaded once there is no interest in keeping the data around.

#[cfg(test)]
mod tests {
    use icu_data;

    #[test]
    fn you_can_also_clone_loaders() {
        let _loader1 = icu_data::Loader::new().expect("loader is constructed with success");
        let _loader2 = icu_data::Loader::new().expect("loader is just fine with a second initialization");
        let _loader3 = _loader2.clone();
        // The ICU data will be unloaded once all loaders go out of scope.
    }
}

Linking

See the build file for details on how to link the library and data. A caveat is that all transitively used non-rust libraries have to be mentioned in the non_rust_deps stanza of any target that uses the icu_data crate.

Testing

To test on your target device, the following sequence of commands should work. The example fx set is for a Chromebook device, but changing to x64 would work if your workflow is based on QEMU, for example.

fx set workstation.chromebook-x64 --with=//src/lib/icu_data/rust:tests
fx build
fx serve
fx run-tests src/lib/icu_data/rust:tests

Run tests like so:

fx run-test icu_data_rust_tests