fix: stablize listing methods in MultipartManifest implementation #727
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Description
This PR fixes some flaky tests found with NonDex, which explores non-determinism in tests. These tests can fail under different JVMs, hash seeds, etc.
The flaky tests:
Root Cause
MultipartManifestImplstorespartsin a HashMap, and listing methods such aslistCompletedParts,listFailedPartsiterate overparts. Since HashMap does not preserve any iteration order, the returned part lists are nondeterministic. However, multipart upload semantics process parts in ascending part number order. This mismatch caused flaky behavior when tests implicitly depend on ordered output.Fix
Following the semantics of part numbers, we can use TreeMap to preserve the parts' order using the keys, with negligible overhead introduced.
Failure Reproduction
Ubuntu 24.04.3 LTSBuild with the main branch and run tests with NonDex to observe the failure, for example:
Notes