Don't emit enum constants for array-typed schemas#2424
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A schema that combines `type: array` with an `enum` is malformed: the enum members are scalars, not arrays, so no array value could ever satisfy the constraint. In the wild this shows up as the item enum being copied onto the array (e.g. Jellyfin's `TranscodingInfo.TranscodeReasons` in issue oapi-codegen#2176). oapi-codegen took the enum branch purely on `len(schema.Enum) > 0`, emitting typed constants while the Go type resolved from `type: array` to a slice. That produced `const X SliceType = ...`, which is not a valid Go constant type: type TranscodingInfoTranscodeReasons []TranscodeReason const TranscodingInfoTranscodeReasonsAnamorphicVideoNotSupported \ TranscodingInfoTranscodeReasons = ... // invalid constant type Guard the enum branch with `!t.Is("array")` so array-typed schemas fall through to normal array handling and generate as a plain `[]ItemType`. The meaningful enum lives on the item schema, which still gets its own constants. No existing fixtures change. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Greptile SummaryThis PR changes enum handling for array-typed schemas in code generation. The main changes are:
Confidence Score: 5/5This looks safe to merge.
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| Filename | Overview |
|---|---|
| pkg/codegen/schema.go | Updates GenerateGoSchema so array-typed enum or const schemas generate as arrays instead of invalid typed constants. |
Reviews (1): Last reviewed commit: "Don't emit enum constants for array-type..." | Re-trigger Greptile
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A schema that combines `type: array` with an `enum` is malformed: the enum members are scalars, not arrays, so no array value could ever satisfy the constraint. In the wild this shows up as the item enum being copied onto the array (e.g. Jellyfin's `TranscodingInfo.TranscodeReasons` in issue oapi-codegen#2176). oapi-codegen took the enum branch purely on `len(schema.Enum) > 0`, emitting typed constants while the Go type resolved from `type: array` to a slice. That produced `const X SliceType = ...`, which is not a valid Go constant type: type TranscodingInfoTranscodeReasons []TranscodeReason const TranscodingInfoTranscodeReasonsAnamorphicVideoNotSupported \ TranscodingInfoTranscodeReasons = ... // invalid constant type Guard the enum branch with `!t.Is("array")` so array-typed schemas fall through to normal array handling and generate as a plain `[]ItemType`. The meaningful enum lives on the item schema, which still gets its own constants. No existing fixtures change. Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Closes: #2176
A schema that combines
type: arraywith anenumis malformed: the enum members are scalars, not arrays, so no array value could ever satisfy the constraint. In the wild this shows up as the item enum being copied onto the array.oapi-codegen took the enum branch purely on
len(schema.Enum) > 0, emitting typed constants while the Go type resolved fromtype: arrayto a slice. That producedconst X SliceType = ..., which is not a valid Go constant type:Guard the enum branch with
!t.Is("array")so array-typed schemas fall through to normal array handling and generate as a plain[]ItemType. The meaningful enum lives on the item schema, which still gets its own constants. No existing fixtures change.