Add x-enum-varnames support

README.md

@@ -168,7 +168,7 @@ json2ts -i foo.json -o foo.d.ts --style.singleQuote --no-style.semi
 ## Custom schema properties:
 
 - `tsType`: Overrides the type that's generated from the schema. Useful for forcing a type to `any` or when using non-standard JSON schema extensions ([eg](https://github.com/sokra/json-schema-to-typescript/blob/f1f40307cf5efa328522bb1c9ae0b0d9e5f367aa/test/e2e/customType.ts)).
-- `tsEnumNames`: Overrides the names used for the elements in an enum. Can also be used to create string enums ([eg](https://github.com/johnbillion/wp-json-schemas/blob/647440573e4a675f15880c95fcca513fdf7a2077/schemas/properties/post-status-name.json)).
+- `'x-enum-varnames'`: Overrides the names used for the elements in an enum. Can also be used to create string enums ([eg](https://github.com/johnbillion/wp-json-schemas/blob/647440573e4a675f15880c95fcca513fdf7a2077/schemas/properties/post-status-name.json)).
 
 ## Not expressible in TypeScript:
 

src/normalizer.ts

@@ -145,6 +145,22 @@ rules.set('Transform const to singleton enum', schema => {
   }
 })
 
+/**
+ * `tsEnumNames` is being replaced by `x-enum-varnames`. Since we don't want to
+ * break existing usage of `tsEnumNames`, we'll convert `tsEnumNames` properties
+ * to `x-enum-varnames`.
+ */
+rules.set('Convert tsEnumNames -> x-enum-varnames', schema => {
+  if (schema.tsEnumNames) {
+    if (Object.keys(schema).includes('x-enum-varnames')) {
+      throw new Error('Cannot set both x-enum-varnames and tsEnumNames in the same schema. Only use x-enum-varnames.')
+    }
+
+    schema['x-enum-varnames'] = schema.tsEnumNames
+    delete schema.tsEnumNames
+  }
+})
+
 export function normalize(rootSchema: LinkedJSONSchema, filename: string, options: Options): NormalizedJSONSchema {
   rules.forEach(rule => traverse(rootSchema, schema => rule(schema, filename, options)))
   return rootSchema as NormalizedJSONSchema

src/parser.ts

@@ -168,7 +168,7 @@ function parseNonLiteral(
         standaloneName: standaloneName(schema, keyNameFromDefinition ?? keyName, usedNames)!,
         params: schema.enum!.map((_, n) => ({
           ast: parse(_, options, undefined, processed, usedNames),
-          keyName: schema.tsEnumNames![n]
+          keyName: schema['x-enum-varnames']![n]
         })),
         type: 'ENUM'
       }

src/types/JSONSchema.ts

@@ -29,6 +29,10 @@ export interface JSONSchema extends JSONSchema4 {
    * schema extension to support numeric enums
    */
   tsEnumNames?: string[]
+  /**
+   * schema extension to support numeric enums
+   */
+  'x-enum-varnames'?: string[]
   /**
    * schema extension to support custom types
    */
@@ -93,10 +97,18 @@ export interface EnumJSONSchema extends NormalizedJSONSchema {
   enum: any[]
 }
 
-export interface NamedEnumJSONSchema extends NormalizedJSONSchema {
+interface DeprecatedNamedEnumJSONSchema extends NormalizedJSONSchema {
+  'x-enum-varnames'?: never
   tsEnumNames: string[]
 }
 
+interface _NamedEnumJSONSchema extends NormalizedJSONSchema {
+  'x-enum-varnames': string[]
+  tsEnumNames?: never
+}
+
+export type NamedEnumJSONSchema = _NamedEnumJSONSchema | DeprecatedNamedEnumJSONSchema
+
 export interface SchemaSchema extends NormalizedJSONSchema {
   properties: {
     [k: string]: NormalizedJSONSchema

src/typesOfSchema.ts

@@ -62,10 +62,10 @@ const matchers: Record<SchemaType, (schema: JSONSchema) => boolean> = {
     return false // Explicitly handled before we try to match
   },
   NAMED_ENUM(schema) {
-    return 'enum' in schema && 'tsEnumNames' in schema
+    return 'enum' in schema && 'x-enum-varnames' in schema
   },
   NAMED_SCHEMA(schema) {
-    return 'id' in schema && ('patternProperties' in schema || 'properties' in schema)
+    return 'id' in schema && 'patternProperties' in schema
   },
   NULL(schema) {
     return schema.type === 'null'
@@ -122,7 +122,7 @@ const matchers: Record<SchemaType, (schema: JSONSchema) => boolean> = {
     return Array.isArray(schema.type)
   },
   UNNAMED_ENUM(schema) {
-    if ('tsEnumNames' in schema) {
+    if ('x-enum-varnames' in schema) {
       return false
     }
     if (

src/validator.ts

@@ -4,12 +4,32 @@ import {mapDeep} from './utils'
 type Rule = (schema: JSONSchema) => boolean | void
 const rules = new Map<string, Rule>()
 
+rules.set('Enum members and x-enum-varnames must be of the same length', schema => {
+  if (schema.enum && schema['x-enum-varnames'] && schema.enum.length !== schema['x-enum-varnames'].length) {
+    return false
+  }
+})
+
+/**
+ * `tsEnumNames` is being replaced by `x-enum-varnames`, but we'll leave this
+ * validator until `tsEnumNames` is removed.
+ */
 rules.set('Enum members and tsEnumNames must be of the same length', schema => {
   if (schema.enum && schema.tsEnumNames && schema.enum.length !== schema.tsEnumNames.length) {
     return false
   }
 })
 
+rules.set('x-enum-varnames must be an array of strings', schema => {
+  if (schema['x-enum-varnames'] && schema['x-enum-varnames'].some(_ => typeof _ !== 'string')) {
+    return false
+  }
+})
+
+/**
+ * `tsEnumNames` is being replaced by `x-enum-varnames`, but we'll leave this
+ * validator until `tsEnumNames` is removed.
+ */
 rules.set('tsEnumNames must be an array of strings', schema => {
   if (schema.tsEnumNames && schema.tsEnumNames.some(_ => typeof _ !== 'string')) {
     return false