Remove uniqueItems from blockStates schema - #1259
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Ajv 6 checks uniqueItems on object arrays with a pairwise deep-equal loop, which is O(n^2). blockStates.json files have ~17k entries, so each of the 29 bedrock versions took 12-36s to validate (~425s of a ~9min CI run); the same file validates in ~11ms without it. Uniqueness of generated block state entries is not an invariant we rely on.
u9g
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The suite used to take ~3min, almost all of it in protodef-validator < 1.5.0 (quadratic dataType validation, PrismarineJS#1259 removed the other hotspot, Ajv's uniqueItems). Require 1.5.0 and assert total suite wall-clock stays under 40s (~20s locally) so a regression shows up in CI.
rom1504
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The suite used to take ~3min, almost all of it in protodef-validator < 1.5.0 (quadratic dataType validation, #1259 removed the other hotspot, Ajv's uniqueItems). Require 1.5.0 and assert total suite wall-clock stays under 40s (~20s locally) so a regression shows up in CI.
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Problem
npm testtakes ~9 minutes. ~425s of that is the 29blockStates.json is validtests (12–36s each).The cause is
"uniqueItems": trueon the top-level array inblockStates_schema.json. Ajv 6 implementsuniqueItemsfor object items with a pairwise deep-equal loop, so with ~17k entries per file it does ~140M comparisons.Measured on
bedrock/1.26.30/blockStates.json(16,913 entries) with ajv 6.15.0:uniqueItems: trueuniqueItems: falseChange
uniqueItemsfrom the schema. The data is generated and uniqueness of state entries isn't an invariant anything relies on (I checked all 29 distinct files: 0 duplicates).test.jsthat was added to accommodate this.Expected effect: CI drops from ~10 min to ~2 min. The remaining time is dominated by
protocol.json is valid, which is fixed upstream in ProtoDef-io/node-protodef-validator#18 and just needs a release + bump.