As of 2024-06-19, Ravenwood uses the host side JVM, not ART, so it doesn't use libcore either.
To support ICU on Ravenwood, we include the following jar files in the Ravenwood classpath.
core-icu4j-for-host.ravenwoodicu4j-icudata-jarjaricu4j-icutzdata-jarjarcore-icu4j-for-host.ravenwood is made from core-icu4j-for-host.ravenwood with hoststubgen to make the following modifications.
android.icu APIs on Ravenwood.libcore_bridge APIS -- will throw at runtime.This “policy” is defined in android_icu4j/icu-ravenwood-policies.txt.
As a result, on Ravenwood, all android.icu APIs will work, but none of the libcore_bridge APIs.
ICU's CTS is CtsIcuTestCases, which contains the tests under android_icu4j/src/main/tests/, which are the tests from the upstream ICU, and android_icu4j/testing/, which are android specific tests, which depends on libcore_bridge.
On Ravenwood, android_icu4j/src/main/tests/ will pass, but not android_icu4j/testing/.
So we have CtsIcuTestCasesRavenwood-core-only, which only contains the tests from the upstream. You can run this with atest CtsIcuTestCasesRavenwood-core-only.