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Stabilize randomized Bazel shards - #3224
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Codecov Report❌ Patch coverage is Additional details and impacted files@@ Coverage Diff @@
## devel #3224 +/- ##
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- Coverage 91.18% 91.16% -0.02%
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Files 205 205
Lines 9101 9103 +2
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horenmar
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Oct 23, 2026
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No. Move the check downwards and account for cases where the RNG seed is properly set.
Catch2 defaults to randomized test order, but Bazel does not set TEST_RANDOM_SEED for ordinary sharding. Independent shard processes can therefore select overlapping cases and omit others. When Bazel enables multiple shards, use declaration order only if the requested order is randomized. Preserve --order=decl and --order=lex, which already have stable membership, and leave non-sharded runs unchanged. Explicitly seeded random order is also replaced by this fallback.
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Description
Catch2 defaults to randomized test order, but Bazel does not set TEST_RANDOM_SEED for ordinary sharding. Independent shard processes can therefore select overlapping cases and omit others.
When Bazel enables multiple shards, use declaration order only if the requested order is randomized. Preserve --order=decl and --order=lex, which already have stable membership, and leave non-sharded runs unchanged. Explicitly seeded random order is also replaced by this fallback.
GitHub Issues
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