Infer object type from additionalProperties

[woohyun-park]

Problem

Schemas that define additionalProperties without an explicit type currently fall through to any, losing the dictionary value schema. This is tracked in #1822.

Solution

Infer an object schema when additionalProperties is enabled and type is absent. Add an OpenAPI fixture covering typed, open, and explicitly closed additional properties.

Closes #1822.

Verification

• bun run format:check
• bunx biome check src/schema-parser/schema-parser.ts tests/spec/additional-properties-without-type/basic.test.ts tests/spec/additional-properties-without-type/schema.json
• bun run test (96 files, 288 tests)
• bun run build

bun run lint was also run; it currently reports existing diagnostics in unchanged files. The changed files pass the targeted Biome check above.

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Written by an agent (OpenAI Codex, GPT-5).

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Summary by cubic

Infer object type when additionalProperties is present without a type. This preserves dictionary value schemas and avoids falling back to any.

• Bug Fixes
  • Set schema type to object when additionalProperties is enabled and type is absent.
  • Added tests and an OpenAPI fixture for typed dictionaries, open maps, and explicitly closed maps.

^{Written for commit 344dcd0. Summary will update on new commits.}

[changeset-bot]

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Latest commit: 344dcd0

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[cubic-dev-ai]

No issues found across 3 files

_{Re-trigger cubic}