An experimental TypeSpec syntax for Lexicon
twk
+27
-8
+27
-8
packages/emitter/src/emitter.ts
+27
-8
packages/emitter/src/emitter.ts
···
421
421
message: `Union has no variants. Atproto unions must contain either model references or string literals.`,
422
422
target: unionType,
423
423
});
424
+
return null;
424
425
}
425
426
426
-
return null;
427
+
// Case 4: Invalid string literal union (has literals but no string type)
428
+
if (variants.stringLiterals.length > 0 && !variants.hasStringType) {
429
+
throw new Error(
430
+
'String literal unions must include "| string" to allow unknown values',
431
+
);
432
+
}
433
+
434
+
// Unexpected case
435
+
throw new Error(
436
+
"Unexpected union type - neither string enum nor model refs nor empty",
437
+
);
427
438
}
428
439
429
440
private parseUnionVariants(unionType: Union) {
···
830
841
return this.addDescription({ type: "unknown" }, propDesc);
831
842
default:
832
843
// Unhandled type kind
833
-
return null;
844
+
throw new Error(
845
+
`TODO: Unhandled type kind "${type.kind}" in typeToLexiconDefinition`,
846
+
);
834
847
}
835
848
}
836
849
···
874
887
return unionDef;
875
888
}
876
889
}
877
-
// TODO: Handle Closed<> with non-union argument
878
-
return null;
890
+
throw new Error(
891
+
"Closed<> template argument must be a union of model references",
892
+
);
879
893
}
880
894
881
895
// 3. Check for model reference (named models from other namespaces)
···
888
902
if (isArrayModelType(this.program, model)) {
889
903
const arrayDef = this.modelToLexiconArray(model, prop);
890
904
if (!arrayDef) {
891
-
// TODO: Handle array conversion failure
892
-
return null;
905
+
throw new Error(
906
+
"Array type conversion failed - array must have a valid item type",
907
+
);
893
908
}
894
909
return this.addDescription(arrayDef, propDesc);
895
910
}
···
1078
1093
1079
1094
if (itemType && isType(itemType)) {
1080
1095
const itemDef = this.typeToLexiconDefinition(itemType);
1081
-
if (!itemDef) return null;
1096
+
if (!itemDef) {
1097
+
throw new Error(
1098
+
"Failed to convert array item type to lexicon definition",
1099
+
);
1100
+
}
1082
1101
1083
1102
const arrayDef: LexiconArray = { type: "array", items: itemDef };
1084
1103
···
1092
1111
return arrayDef;
1093
1112
}
1094
1113
1095
-
return null;
1114
+
throw new Error("Array type must have a valid item type argument");
1096
1115
}
1097
1116
1098
1117
private getLexiconPath(lexiconId: string): string {