Fix string-enum codegen to compile against wasm-bindgen#30
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The string-enum output had never been compiled against wasm-bindgen. The snapshot tests only compare text, so several constructs slipped through that wasm-bindgen rejects. Surfaced while generating Cloudflare's Vectorize bindings (the `$eq` / `$in` metadata filter operators and the `returnMetadata: boolean | <enum>` union). Four fixes: - enums.rs: emit string enums in the discriminant form (`Variant = "value"`) rather than a per-variant `#[wasm_bindgen(js_name = "...")]` attribute, which wasm-bindgen does not accept on enum variants. - typemap.rs: pass string/numeric enums by value in argument position. They lower to `Copy` enums whose `IntoWasmAbi` is implemented by value, so `&Enum` fails to satisfy `IntoWasmAbi`. Adds `CodegenContext::value_enum_kind` / `resolves_to_value_enum` and the `ValueEnumKind` type. - mod.rs: when a union member is a string/numeric enum, lower it to its `JsString` / `Number` wrapper. Value enums don't implement `JsCast`, so they can't be a wasm-bindgen union-enum payload directly, but the wrapper carries the same FFI value. - naming.rs: strip leading non-alphanumerics in `to_enum_variant` before PascalCasing, so `$eq` -> `Eq` and `$in` -> `In` (the latter also dodges the `in` keyword) instead of `eq` / `r#in`. Snapshots re-blessed; only string-enum/union output changes.
guybedford
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Jun 23, 2026
guybedford
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Great work, thank you.
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| @@ -41558,7 +41168,7 @@ pub enum TlsClientAuthKind { | |||
| } | |||
| #[wasm_bindgen] | |||
| pub enum CountryKind { | |||
| Iso3166Alpha2Code(Iso3166Alpha2Code), | |||
| JsString(JsString), | |||
| T1 = "T1", | |||
| } | |||
| #[wasm_bindgen] | |||
| @@ -41730,7 +41340,7 @@ pub enum AttributeValueKind { | |||
| #[wasm_bindgen] | |||
| pub enum ReturnMetadataKind { | |||
| Bool(bool), | |||
| VectorizeMetadataRetrievalLevel(VectorizeMetadataRetrievalLevel), | |||
| JsString(JsString), | |||
| } | |||
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These seem to have been dropped somehow?
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Iso3166Alpha2Code(Iso3166Alpha2Code) / VectorizeMetadataRetrievalLevel(VectorizeMetadataRetrievalLevel) don't impl JsCast so this code would fail to compile. This change lowers to JsString so it does compile.
error[E0277]: the trait bound `Iso3166Alpha2Code: TryFromJsValue` is not satisfied
--> src/lib.rs:14:23
14 | Iso3166Alpha2Code(Iso3166Alpha2Code),
| ^^^^^^^^^^^^^^^^^ unsatisfied trait bound
help: the trait `JsCast` is not implemented for `Iso3166Alpha2Code`
= note: required for `Iso3166Alpha2Code` to implement `TryFromJsValue`
does this not seem right to you?
integration test caught that the fix wasnt applied to module scoped enums
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The string-enum output had never been compiled against wasm-bindgen. The snapshot tests only compare text, so several constructs slipped through that wasm-bindgen rejects. Surfaced while generating Cloudflare's Vectorize bindings (the
$eq/$inmetadata filter operators and thereturnMetadata: boolean | <enum>union). Four fixes:enums.rs: emit string enums in the discriminant form (
Variant = "value") rather than a per-variant#[wasm_bindgen(js_name = "...")]attribute, which wasm-bindgen does not accept on enum variants.typemap.rs: pass string/numeric enums by value in argument position. They lower to
Copyenums whoseIntoWasmAbiis implemented by value, so&Enumfails to satisfyIntoWasmAbi. AddsCodegenContext::value_enum_kind/resolves_to_value_enumand theValueEnumKindtype.mod.rs: when a union member is a string/numeric enum, lower it to its
JsString/Numberwrapper. Value enums don't implementJsCast, so they can't be a wasm-bindgen union-enum payload directly, but the wrapper carries the same FFI value.naming.rs: strip leading non-alphanumerics in
to_enum_variantbefore PascalCasing, so$eq->Eqand$in->In(the latter also dodges theinkeyword) instead ofeq/r#in.Snapshots re-blessed; only string-enum/union output changes.