Factorize parenthesise function and apply it to arrays

Author: tkrotoff

packages/openapi-typescript/src/utils.ts

@@ -168,17 +168,22 @@ export function encodeRef(ref: string): string {
   return ref.replace(TILDE_RE, "~0").replace(FS_RE, "~1");
 }
 
+/** if the type has & or | we should parenthesise it for safety */
+function parenthesise(type: string) {
+  return TS_UNION_INTERSECTION_RE.test(type) ? `(${type})` : type;
+}
+
 /** T[] */
 export function tsArrayOf(type: string): string {
-  return `(${type})[]`;
+  return `${parenthesise(type)}[]`;
 }
 
 /** X & Y & Z; */
 export function tsIntersectionOf(...types: string[]): string {
   types = types.filter((t) => t !== "unknown");
   if (types.length === 0) return "unknown";
   if (types.length === 1) return String(types[0]); // don’t add parentheses around one thing
-  return types.map((t) => (TS_UNION_INTERSECTION_RE.test(t) ? `(${t})` : t)).join(" & ");
+  return types.map((t) => parenthesise(t)).join(" & ");
 }
 
 /** NonNullable<T> */
@@ -258,11 +263,7 @@ export function tsUnionOf(...types: (string | number | boolean)[]): string {
   let out = "";
   for (let i = 0; i < memberArr.length; i++) {
     const t = memberArr[i];
-
-    // if the type has & or | we should parenthesise it for safety
-    const escaped = TS_UNION_INTERSECTION_RE.test(t) ? `(${t})` : t;
-
-    out += escaped;
+    out += parenthesise(t);
     if (i !== memberArr.length - 1) out += " | ";
   }
 

packages/openapi-typescript/test/schema-object.test.ts

@@ -97,7 +97,7 @@ describe("Schema Object", () => {
       test("basic", () => {
         const schema: SchemaObject = { type: "array", items: { type: "string" } };
         const generated = transformSchemaObject(schema, options);
-        expect(generated).toBe("(string)[]");
+        expect(generated).toBe("string[]");
       });
 
       test("tuple array", () => {
@@ -109,7 +109,7 @@ describe("Schema Object", () => {
       test("ref", () => {
         const schema: SchemaObject = { type: "array", items: { $ref: 'components["schemas"]["ArrayItem"]' } };
         const generated = transformSchemaObject(schema, options);
-        expect(generated).toBe('(components["schemas"]["ArrayItem"])[]');
+        expect(generated).toBe('components["schemas"]["ArrayItem"][]');
       });
     });
 
@@ -267,7 +267,7 @@ describe("Schema Object", () => {
 
         test("array", () => {
           const generated = transformSchemaObject({ type: "array", items: { type: "string" }, nullable: true }, options);
-          expect(generated).toBe("(string)[] | null");
+          expect(generated).toBe("string[] | null");
         });
 
         test("object", () => {
@@ -301,7 +301,7 @@ describe("Schema Object", () => {
 
         test("array", () => {
           const generated = transformSchemaObject({ type: ["array", "null"], items: { type: "string" } } as any, options);
-          expect(generated).toBe("(string)[] | null");
+          expect(generated).toBe("string[] | null");
         });
 
         test("object", () => {
@@ -405,7 +405,7 @@ describe("Schema Object", () => {
 } | {
   number: number;
 } | {
-  array: (string)[];
+  array: string[];
 } | {
   object: {
     string: string;
@@ -606,10 +606,10 @@ describe("Schema Object", () => {
 
     test("supportArrayLength", () => {
       const opts = { ...options, ctx: { ...options.ctx, supportArrayLength: true } };
-      expect(transformSchemaObject({ type: "array", items: { type: "string" } }, options)).toBe(`(string)[]`);
-      expect(transformSchemaObject({ type: "array", items: { type: "string" }, minItems: 1 }, opts)).toBe(`[string, ...(string)[]]`);
+      expect(transformSchemaObject({ type: "array", items: { type: "string" } }, options)).toBe(`string[]`);
+      expect(transformSchemaObject({ type: "array", items: { type: "string" }, minItems: 1 }, opts)).toBe(`[string, ...string[]]`);
       expect(transformSchemaObject({ type: "array", items: { type: "string" }, maxItems: 2 }, opts)).toBe(`[] | [string] | [string, string]`);
-      expect(transformSchemaObject({ type: "array", items: { type: "string" }, maxItems: 20 }, opts)).toBe(`(string)[]`);
+      expect(transformSchemaObject({ type: "array", items: { type: "string" }, maxItems: 20 }, opts)).toBe(`string[]`);
     });
 
     test("prefixItems", () => {
@@ -642,9 +642,9 @@ describe("Schema Object", () => {
           ctx: { ...options.ctx, immutableTypes: true },
         });
         expect(generated).toBe(`{
-  readonly array?: readonly ({
+  readonly array?: readonly {
       [key: string]: unknown;
-    })[] | null;
+    }[] | null;
 }`);
       });
     });