docs: clarify anyOf nullable coercion behavior with primitive types#6531
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mcollina merged 1 commit intofastify:mainfrom Feb 28, 2026
Merged
docs: clarify anyOf nullable coercion behavior with primitive types#6531mcollina merged 1 commit intofastify:mainfrom
mcollina merged 1 commit intofastify:mainfrom
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When type coercion is enabled, using anyOf with a null type before a primitive type (number, boolean) causes Ajv to coerce falsy values like 0 and false to null. Document this pitfall and recommend using the nullable keyword instead. Fixes fastify#6411
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When type coercion is enabled, using
anyOfwith anulltype before a primitive type (number,boolean) causes Ajv to coerce falsy values like0andfalsetonull. This documents the pitfall and recommends using thenullablekeyword instead.Fixes #6411
This picks up where #6429 left off (which was closed after an accidental merge/revert).
Checklist
npm run lintpasses