Ignore `uniqueItems` when set to `false` while importing JSON Schema documents by fubhy · Pull Request #6924 · Effect-TS/effect

fubhy · 2026-08-03T19:29:54Z

Summary

Importing a JSON Schema array with uniqueItems set to false rejects duplicate elements.

Important

This PR starts with focused failing reproduction tests. Add the implementation fix to this same branch; CI is expected to fail until that fix is included.

uniqueItems false enables uniqueness

Module: SchemaRepresentation
Audit ID: core-s-z-testing-schema-representation-unique-items-false
Severity / confidence: medium / high

What happens

Importing a JSON Schema array with uniqueItems set to false rejects duplicate elements.

Why it happens

collectArrayChecks adds the effect/schema/isUnique filter for either boolean value, so the importer strengthens a valid external schema and rejects values it must accept.

Expected behavior

JSON Schema Draft 2020-12 uniqueItems: false imposes no uniqueness constraint.

Relevant implementation

These links and excerpts are pinned to audit base c9b56ab507f224426ee8388dc450da447ec4715f.

packages/effect/src/internal/schema/fromJsonSchemaDocument.ts:811-820

View problematic code at packages/effect/src/internal/schema/fromJsonSchemaDocument.ts:811-820

  function collectArrayChecks(schema: JsonSchema.JsonSchema): Array<Check> {
    const checks: Array<Check> = []
    if (schema.prefixItems === undefined) {
      addNumberCheck(checks, schema.minItems, "effect/schema/isMinLength", "minLength")
      addNumberCheck(checks, schema.maxItems, "effect/schema/isMaxLength", "maxLength")
    }
    if (typeof schema.uniqueItems === "boolean") {
      checks.push(jsonSchemaFilter("effect/schema/isUnique", null))
    }
    return checks

View exact lines on GitHub

Reproduction

pnpm test --run packages/effect/test/schema/representation/fromJsonSchemaDocument.test.ts -t "does not require uniqueness when uniqueItems is false"

Observed failure: validity false instead of true

Implementation handoff

The initial reproduction tests on this branch are the regression specification for the implementation fix that should follow in this PR.

Start with the pinned implementation excerpts and the Why it happens analysis above.
Change the implementation so it satisfies the stated Expected behavior; do not weaken or remove the reproduction assertions.
Run the focused reproduction command(s) and confirm the observed failures become passing tests:

pnpm test --run packages/effect/test/schema/representation/fromJsonSchemaDocument.test.ts -t "does not require uniqueness when uniqueItems is false"

Run the affected package's existing tests, then the repository lint and type checks before requesting review.

Audit provenance

Audit base: c9b56ab507f224426ee8388dc450da447ec4715f
Reproduction base: c9b56ab507f224426ee8388dc450da447ec4715f
Findings: core-s-z-testing-schema-representation-unique-items-false
Initial patch: focused reproduction tests; implementation fix pending

changeset-bot · 2026-08-03T19:29:59Z

🦋 Changeset detected

Latest commit: c83020b

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 30 packages

Name	Type
effect	Patch
@effect/opentelemetry	Patch
@effect/platform-browser	Patch
@effect/platform-bun	Patch
@effect/platform-deno	Patch
@effect/platform-node-shared	Patch
@effect/platform-node	Patch
@effect/vitest	Patch
@effect/ai-anthropic	Patch
@effect/ai-openai-compat	Patch
@effect/ai-openai	Patch
@effect/ai-openrouter	Patch
@effect/atom-react	Patch
@effect/atom-solid	Patch
@effect/atom-vue	Patch
@effect/sql-clickhouse	Patch
@effect/sql-d1	Patch
@effect/sql-libsql	Patch
@effect/sql-mssql	Patch
@effect/sql-mysql2	Patch
@effect/sql-pg	Patch
@effect/sql-pglite	Patch
@effect/sql-sqlite-bun	Patch
@effect/sql-sqlite-do	Patch
@effect/sql-sqlite-node	Patch
@effect/sql-sqlite-react-native	Patch
@effect/sql-sqlite-wasm	Patch
@effect/docgen	Patch
@effect/doctest	Patch
@effect/openapi-generator	Patch

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pullfrog

Important

The reproduction test is correct and verifies the expected behavior, but the implementation fix at fromJsonSchemaDocument.ts:817 still needs to be applied.

Reviewed changes

Reproduction test for uniqueItems: false: Adds a test confirming that uniqueItems: false does not impose a uniqueness constraint — ["a", "a"] should validate as true. Confirmed the test correctly fails against the current code.

⚠️ Implementation fix still needed

The test is a faithful reproduction, but collectArrayChecks still adds isUnique for any boolean uniqueItems value.

Technical details

# Tighten `uniqueItems` guard to `true` only

## Affected sites
- `packages/effect/src/internal/schema/fromJsonSchemaDocument.ts:817` — `typeof schema.uniqueItems === "boolean"` pushes `isUnique` for both `true` and `false`, adding a uniqueness constraint even when it is explicitly disclaimed.

## Required outcome
- Change the guard so `uniqueItems: false` yields no `isUnique` check.

## Suggested approach
- Replace `typeof schema.uniqueItems === "boolean"` with `schema.uniqueItems === true` on line 817.
- No callers or tests should regress — the existing `uniqueItems: true` test at `fromJsonSchemaDocument.test.ts:1696` will continue to pass, and the new test will go green.

^{｜ Fix it ➔ ｜ View workflow run ｜ Using DeepSeek Pro (free via Pullfrog for OSS) (Kimi K2 not used — the program covers this model; add its provider key to run your pick) ｜ 𝕏}

pullfrog

✅ No new issues found.

Reviewed changes

Applied the uniqueItems === true guard: Changed collectArrayChecks from typeof schema.uniqueItems === "boolean" to schema.uniqueItems === true so that uniqueItems: false no longer pushes an isUnique filter.
Added patch changeset: effect patch-level changeset describing the fix.

The implementation matches the suggested fix from the prior review exactly. The new reproduction test passes, and the existing uniqueItems: true test is unaffected.

^{｜ View workflow run ｜ Using DeepSeek Pro (free via Pullfrog for OSS) (Kimi K2 not used — the program covers this model; add its provider key to run your pick) ｜ 𝕏}

github-actions · 2026-08-03T20:27:54Z

Bundle Size Analysis

Generated from PR build output; treat the content below as untrusted.

File Name	Current Size	Previous Size	Difference
`basic.ts`	7.06 KB	7.06 KB	0.00 KB (0.00%)
`batching.ts`	9.86 KB	9.86 KB	0.00 KB (0.00%)
`brand.ts`	6.34 KB	6.34 KB	0.00 KB (0.00%)
`cache.ts`	10.62 KB	10.62 KB	0.00 KB (0.00%)
`config.ts`	20.60 KB	20.60 KB	0.00 KB (0.00%)
`differ.ts`	20.20 KB	20.20 KB	0.00 KB (0.00%)
`http-client.ts`	21.49 KB	21.49 KB	0.00 KB (0.00%)
`logger.ts`	10.76 KB	10.76 KB	0.00 KB (0.00%)
`metric.ts`	8.99 KB	8.99 KB	0.00 KB (0.00%)
`optic.ts`	7.18 KB	7.18 KB	0.00 KB (0.00%)
`pubsub.ts`	14.90 KB	14.90 KB	0.00 KB (0.00%)
`queue.ts`	11.58 KB	11.58 KB	0.00 KB (0.00%)
`schedule.ts`	10.74 KB	10.74 KB	0.00 KB (0.00%)
`schema-class.ts`	19.14 KB	19.14 KB	0.00 KB (0.00%)
`schema-fromJsonSchemaDocument.ts`	28.96 KB	28.96 KB	+0.00 KB (+0.00%)
`schema-representation-roundtrip.ts`	25.29 KB	25.29 KB	0.00 KB (0.00%)
`schema-string-transformation.ts`	13.30 KB	13.30 KB	0.00 KB (0.00%)
`schema-string.ts`	10.94 KB	10.94 KB	0.00 KB (0.00%)
`schema-template-literal.ts`	15.17 KB	15.17 KB	0.00 KB (0.00%)
`schema-toArbitraryLazy.ts`	21.94 KB	21.94 KB	0.00 KB (0.00%)
`schema-toCodeDocument.ts`	24.34 KB	24.34 KB	0.00 KB (0.00%)
`schema-toCodecJson.ts`	19.18 KB	19.18 KB	0.00 KB (0.00%)
`schema-toEquivalence.ts`	19.01 KB	19.01 KB	0.00 KB (0.00%)
`schema-toFormatter.ts`	18.87 KB	18.87 KB	0.00 KB (0.00%)
`schema-toJsonSchemaDocument.ts`	22.60 KB	22.60 KB	0.00 KB (0.00%)
`schema-toRepresentation.ts`	19.52 KB	19.52 KB	0.00 KB (0.00%)
`schema.ts`	18.41 KB	18.41 KB	0.00 KB (0.00%)
`stm.ts`	12.54 KB	12.54 KB	0.00 KB (0.00%)
`stream.ts`	9.79 KB	9.79 KB	0.00 KB (0.00%)

fubhy added the audit Findings originating from the Effect runtime correctness audit label Aug 3, 2026

github-project-automation Bot added this to PR Backlog Aug 3, 2026

github-project-automation Bot moved this to Discussion Ongoing in PR Backlog Aug 3, 2026

fubhy requested a review from gcanti August 3, 2026 19:30

pullfrog Bot reviewed Aug 3, 2026

View reviewed changes

gcanti changed the title ~~Ignore uniqueItems when false in SchemaRepresentation imports~~ Ignore uniqueItems when set to false while importing JSON Schema documents Aug 3, 2026

fubhy and others added 2 commits August 3, 2026 22:22

Ignore uniqueItems when false in SchemaRepresentation imports

5cbd45b

Fix uniqueItems false JSON Schema imports

c83020b

gcanti force-pushed the audit/repro-core-schemarepresentation-uniqueitems-false branch from c0a7b6d to c83020b Compare August 3, 2026 20:22

pullfrog Bot approved these changes Aug 3, 2026

View reviewed changes

gcanti merged commit a94cbed into main Aug 3, 2026
17 checks passed

gcanti deleted the audit/repro-core-schemarepresentation-uniqueitems-false branch August 3, 2026 20:28

github-project-automation Bot moved this from Discussion Ongoing to Done in PR Backlog Aug 3, 2026

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Ignore `uniqueItems` when set to `false` while importing JSON Schema documents - #6924

Ignore `uniqueItems` when set to `false` while importing JSON Schema documents#6924
gcanti merged 2 commits into
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audit/repro-core-schemarepresentation-uniqueitems-false

fubhy commented Aug 3, 2026

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fubhy commented Aug 3, 2026

Summary

uniqueItems false enables uniqueness

What happens

Why it happens

Expected behavior

Relevant implementation

Reproduction

Implementation handoff

Audit provenance

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changeset-bot Bot commented Aug 3, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

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🦋 Changeset detected

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⚠️ Implementation fix still needed

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github-actions Bot commented Aug 3, 2026

Bundle Size Analysis

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changeset-bot Bot commented Aug 3, 2026 •

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