FIX: no longer adding undefined for ZodOptional.

RobinTail · RobinTail · commit 773b212f5192 · 2025-05-05T13:26:06.000+02:00
diff --git a/example/example.client.ts b/example/example.client.ts
@@ -1,6 +1,6 @@
 type Type1 = {
   title: string;
-  features?: Type1[] | undefined;
+  features?: Type1[];
 };
 
 type SomeOf<T> = T[keyof T];
@@ -265,15 +265,15 @@ interface PostV1AvatarRawNegativeResponseVariants {
 /** get /v1/events/stream */
 type GetV1EventsStreamInput = {
   /** @deprecated for testing error response */
-  trigger?: string | undefined;
+  trigger?: string;
 };
 
 /** get /v1/events/stream */
 type GetV1EventsStreamPositiveVariant1 = {
   data: number;
   event: "time";
-  id?: string | undefined;
-  retry?: number | undefined;
+  id?: string;
+  retry?: number;
 };
 
 /** get /v1/events/stream */
diff --git a/express-zod-api/src/zts.ts b/express-zod-api/src/zts.ts
@@ -119,10 +119,7 @@ const makeSample = (produced: ts.TypeNode) =>
   samples?.[produced.kind as keyof typeof samples];
 
 const onOptional: Producer = ({ _zod: { def } }: $ZodOptional, { next }) =>
-  f.createUnionTypeNode([
-    next(def.innerType),
-    ensureTypeNode(ts.SyntaxKind.UndefinedKeyword),
-  ]);
+  next(def.innerType);
 
 const onNullable: Producer = ({ _zod: { def } }: $ZodNullable, { next }) =>
   f.createUnionTypeNode([next(def.innerType), makeLiteralType(null)]);
diff --git a/express-zod-api/tests/__snapshots__/integration.spec.ts.snap b/express-zod-api/tests/__snapshots__/integration.spec.ts.snap
@@ -282,14 +282,14 @@ exports[`Integration > Should treat optionals the same way as z.infer() by defau
 
 /** post /v1/test-with-dashes */
 type PostV1TestWithDashesInput = {
-  opt?: string | undefined;
+  opt?: string;
 };
 
 /** post /v1/test-with-dashes */
 type PostV1TestWithDashesPositiveVariant1 = {
   status: "success";
   data: {
-    similar?: number | undefined;
+    similar?: number;
   };
 };
 
diff --git a/express-zod-api/tests/__snapshots__/zts.spec.ts.snap b/express-zod-api/tests/__snapshots__/zts.spec.ts.snap
@@ -22,14 +22,14 @@ exports[`zod-to-ts > Example > should produce the expected results 1`] = `
     any: any;
     unknown: any;
     never: any;
-    optionalString?: string | undefined;
+    optionalString?: string;
     nullablePartialObject: {
-        string?: string | undefined;
-        number?: number | undefined;
-        fixedArrayOfString?: string[] | undefined;
+        string?: string;
+        number?: number;
+        fixedArrayOfString?: string[];
         object?: {
             string: string;
-        } | undefined;
+        };
     } | null;
     tuple: [
         string,
@@ -57,8 +57,8 @@ exports[`zod-to-ts > Example > should produce the expected results 1`] = `
     set: any;
     intersection: (string & number) | bigint;
     promise: any;
-    optDefaultString?: string | undefined;
-    refinedStringWithSomeBullshit: (string | number) & ((bigint | null) | undefined);
+    optDefaultString?: string;
+    refinedStringWithSomeBullshit: (string | number) & (bigint | null);
     nativeEnum: "A" | "apple" | "banana" | "cantaloupe" | 5;
     lazy: SomeType;
     discUnion: {
@@ -127,15 +127,15 @@ exports[`zod-to-ts > Issue #2352: intersection of objects having same prop %# >
 "{
     query: string;
 } & {
-    query?: string | undefined;
+    query?: string;
 }"
 `;
 
 exports[`zod-to-ts > Issue #2352: intersection of objects having same prop %# > should not flatten the result for objects with a conflicting prop 3 1`] = `
 "{
     query: string;
 } & {
-    query?: string | undefined;
+    query?: string;
 }"
 `;
 
@@ -268,21 +268,21 @@ exports[`zod-to-ts > z.object() > supports zod.describe() 1`] = `
 }"
 `;
 
+exports[`zod-to-ts > z.optional() > Zod 4: does not add undefined to it, unwrap as is 1`] = `"string"`;
+
 exports[`zod-to-ts > z.optional() > Zod 4: should add question mark only to optional props 1`] = `
 "{
-    optional?: string | undefined;
+    optional?: string;
     required: string;
-    transform: number | undefined;
-    or: (number | undefined) | string;
+    transform: number;
+    or: number | string;
     tuple?: [
-        string | undefined,
+        string,
         number,
         {
-            optional?: string | undefined;
+            optional?: string;
             required: string;
         }
-    ] | undefined;
+    ];
 }"
 `;
-
-exports[`zod-to-ts > z.optional() > outputs correct typescript 1`] = `"string | undefined"`;
diff --git a/express-zod-api/tests/zts.spec.ts b/express-zod-api/tests/zts.spec.ts
@@ -202,7 +202,7 @@ describe("zod-to-ts", () => {
         .optional(),
     });
 
-    test("outputs correct typescript", () => {
+    test("Zod 4: does not add undefined to it, unwrap as is", () => {
       const node = zodToTs(optionalStringSchema, { ctx });
       expect(printNodeTest(node)).toMatchSnapshot();
     });
