fix: support enums with single value (#33) (#34)

Author: mankdev

src/language/typescript.ts

@@ -362,7 +362,10 @@ const serializeSchemaObject = (schema: TSchemaObject, rootName: string, cwd: str
 
 const serializeEnum = (enumValue: Array<string | number | boolean>): TSerializedType => {
 	const type = enumValue.map(value => `'${value}'`).join(' | ');
-	const io = `union([${enumValue.map(value => `literal('${value}')`).join(',')}])`;
+	const io =
+		enumValue.length === 1
+			? `literal(${type})`
+			: `union([${enumValue.map(value => `literal('${value}')`).join(',')}])`;
 	return serializedType(type, io, [dependency('union', 'io-ts'), dependency('literal', 'io-ts')], EMPTY_REFS);
 };
 

test/specs/json/common.json

@@ -34,6 +34,11 @@
             "delivered"
           ]
         },
+        "state" : {
+          "type" : "string",
+          "description" : "order state",
+          "enum" : [ "ACTIVE" ]
+        },
         "complete": {
           "type": "boolean",
           "default": false