Crate icu_testdata[][src]

Expand description

icu_testdata is a unit testing package for ICU4X.

The package exposes a DataProvider with stable data useful for unit testing. The data is based on a CLDR tag and a short list of locales that, together, cover a range of scenarios.

The list of locales and the current CLDR tag can be found in Cargo.toml.

The output data can be found in the data subdirectory. There, you will find:

  • json for the ICU4X JSON test data
  • cldr for the source CLDR JSON

Pointing to custom test data

If you wish to run ICU4X tests with custom test data, you may do so by setting the “ICU4X_TESTDATA_DIR” environment variable:

$ ICU4X_TESTDATA_DIR=/path/to/custom/testdata cargo test

Re-generating the data

From the top level directory of the icu4x metapackage, run:

$ cargo make testdata

The following commands are also available:

  • cargo make testdata-download downloads fresh CLDR JSON without overwriting ICU4X JSON
  • cargo make testdata-build-json re-generates the ICU4X JSON
  • cargo make bincode-gen-testdata generates Bincode testdata


use std::borrow::Cow;
use icu_provider::prelude::*;
use icu_locid_macros::langid;

let data_provider = icu_testdata::get_provider();

let data: DataPayload<icu_plurals::provider::PluralRuleStringsV1Marker> = data_provider
    .load_payload(&DataRequest {
        resource_path: ResourcePath {
            key: icu_plurals::provider::key::CARDINAL_V1,
            options: ResourceOptions {
                langid: Some(langid!("ru")),
                variant: None,
assert_eq!(data.get().few, Some(Cow::Borrowed("v = 0 and i % 10 = 2..4 and i % 100 != 12..14")));



Get a DataProvider, loading from the test data JSON directory. Panics if unable to load the data.

Get a DataProvider, loading from the statically initialized bincode blob. Panics if unable to load the data.