Improve Android Core Library Desugaring trait - #910
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madsodgaard
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ktoso
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Sep 4, 2026
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The previous work we had done for Android core library desugaring was purely a compile-time thing. However, it should really be a runtime thing. For example, if you have two apps:
minSdk: 23minSdk: 24On App A,
java.util.Optionalis desugared toj$.util.OptionalOn App B,
java.util.Optionalis availablePreviously, our trait would embed the desugared name into the binary That would mean if we enabled the trait to allow
Optionaluse on API 23, then the same binary would fail on a project withminSdk: 24.This PR refactors the trait to instead be a runtime "probe", that checks whether the desugared is available or not, and caches that for future use.
It also fixes a bug where we would not use the desugared name in
JNIMethodCache, which would results in crashes for collections of optionals for example.