Add generate-time suite sharding (--shard-count / --shard-index)#161
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Splits the generated suite into N deterministic, disjoint slices so a CI matrix can compile and run them on separate runners in parallel. Assignment is a stable FNV-1a hash of the test file name (not string.GetHashCode, which is per-process randomized), so shard k always holds the same files across runs/machines/OSes, shards never overlap, and their union is the full suite. Strict and non-strict variants of a file share a shard. Wired through TestSuiteGeneratorOptions, the generator, and the console tool. Added partition/determinism/validation tests; existing snapshots unaffected. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Adds optional sharding to
generateso a CI matrix can compile and run independent slices of the suite on separate runners in parallel.What
--shard-count(default 1 = no sharding) and--shard-index([0, shard-count)) on thegeneratecommand, plumbed throughTestSuiteGeneratorOptions.string.GetHashCode(), which is per-process randomized on modern .NET. So shard k always contains the same files across runs, machines and operating systems; shards never overlap; and their union is exactly the full suite. Strict and non-strict variants of a file share a shard, and a shard generated on one OS can be reused (e.g. from a cross-OS cache) by test jobs on any other.Validation
Console run against a real test262 checkout,
--shard-count 4:New tests cover partition (no overlap / no loss), determinism, and argument validation. Existing snapshot tests are unaffected (10/10 pass).
Motivation
Consumed by Jint to shard its ~99.5k-case Test262 run across parallel GitHub Actions runners (the suite execution dominates CI wall-clock, and free runners are capped at 4 vCPU which NUnit already saturates — so horizontal sharding is the only lever left).
🤖 Generated with Claude Code