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When a Compose-compiler-generated class like `ComposableSingletons$MainActivityKt`
is inlined through an R8 synthetic lambda, the outer Kotlin class has no
top-level declaration in the mapping (only its `$$ExternalSyntheticLambda*`
children). The synthesizer previously took `split('$').next()`, collapsing
`ComposableSingletons$MainActivityKt` to `ComposableSingletons` and producing
`ComposableSingletons.java`.
Scan all `$`-separated segments for a Kotlin file-class marker (ends in `Kt`)
so the inner `MainActivityKt` segment wins and the file resolves to
`MainActivity.kt`. Bare top-level `FooKt` and non-Kotlin inner classes are
unaffected.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
…ader Merge the restored "Kt suffix takes precedence" note back into the scan-loop comment, and rename the test block header from `ComposableSingletonsInlinedLambdaStackTrace` to a plain description — the sibling blocks in this file name upstream R8 retrace fixtures, which this case is not. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Dav1dde
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loewenheim
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Replace the prose `For example:` list in the doc comment with actual unit tests covering the full matrix — top-level Kt, Kt-over-reference-file, reference-file extension, non-Kotlin inner class, ComposableSingletons wrapper, degenerate bare `Kt` segment, default `.java` fallback. Also convert the block `// ====` header on COMPOSABLE_SINGLETONS_INLINED_LAMBDA_MAPPING into a `///` doc comment on the constant, per review feedback. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Bumps `proguard` from 5.10.2 to 5.10.3 to pick up the `ComposableSingletons$FileKt` source-file synthesis fix from [getsentry/rust-proguard#94](getsentry/rust-proguard#94). When a Compose-generated `ComposableSingletons$MainActivityKt` class is inlined through an R8 synthetic lambda and no top-level class declaration exists for it in the mapping (common in Android builds), the previous `synthesize_source_file` truncated at the first `$` and produced `ComposableSingletons.java`. 5.10.3 scans every `$`-segment for a `Kt` marker and now resolves to `MainActivity.kt`. No symbolicator-side changes are needed — the fix is entirely inside the leaf utility. Upstream carries unit tests (7 cases in `src/utils.rs`) and an integration test (`tests/r8-source-file-edge-cases.rs::test_composable_singletons_inlined_lambda_stacktrace`). Skipping an end-to-end integration test here since there's no new data flow or wiring to exercise on this side; happy to add one if reviewers prefer. Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Fix synthesized source filenames for Compose-compiler-generated
ComposableSingletons$FileKtclasses when they are inlined through R8 synthetic lambdas.When a Compose compilation emits a
ComposableSingletons$MainActivityKtclass, the mapping often does not include a top-level declaration for it — only its$$ExternalSyntheticLambda*siblings appear, each carryingsourceFile: R8$$SyntheticClass. In that case the outer Kotlin class has nosourceFilemetadata of its own, and frame resolution falls back tosynthesize_source_file, which previously didsplit('$').next()and collapsedComposableSingletons$MainActivityKttoComposableSingletons. The resulting frame's filename becameComposableSingletons.java, dropping the realMainActivity.kt.The fix scans every
$-separated segment of the last dotted component for a Kotlin file-class marker (ends inKt). The innerMainActivityKtsegment now wins and producesMainActivity.kt. Bare top-level Kotlin classes (FooKt) and non-Kotlin inner classes (Foo$Bar→Foo.java) are unchanged — they still resolve on the first iteration exactly as before.Includes a minimal reproducer in
tests/r8-source-file-edge-cases.rsmirroring the scenario: aComposableSingletons$MyScreenKtlambda inlined through an$$ExternalSyntheticLambdawhosesourceFileisR8$$SyntheticClass.