Unwiden catch input type (#4870)

Author: colinhacks

packages/zod/src/v4/classic/tests/catch.test.ts

@@ -1,6 +1,5 @@
 import { expect, expectTypeOf, test } from "vitest";
 import { z } from "zod/v4";
-import type { util } from "zod/v4/core";
 
 test("basic catch", () => {
   expect(z.string().catch("default").parse(undefined)).toBe("default");
@@ -45,7 +44,7 @@ test("catch with transform", () => {
   expect(stringWithDefault.unwrap().out).toBeInstanceOf(z.ZodTransform);
 
   type inp = z.input<typeof stringWithDefault>;
-  expectTypeOf<inp>().toEqualTypeOf<string | util.Whatever>();
+  expectTypeOf<inp>().toEqualTypeOf<string>();
   type out = z.output<typeof stringWithDefault>;
   expectTypeOf<out>().toEqualTypeOf<string>();
 });
@@ -59,7 +58,7 @@ test("catch on existing optional", () => {
   expect(stringWithDefault.unwrap().unwrap()).toBeInstanceOf(z.ZodString);
 
   type inp = z.input<typeof stringWithDefault>;
-  expectTypeOf<inp>().toEqualTypeOf<string | undefined | util.Whatever>();
+  expectTypeOf<inp>().toEqualTypeOf<string | undefined>();
   type out = z.output<typeof stringWithDefault>;
   expectTypeOf<out>().toEqualTypeOf<string | undefined>();
 });
@@ -68,7 +67,7 @@ test("optional on catch", () => {
   const stringWithDefault = z.string().catch("asdf").optional();
 
   type inp = z.input<typeof stringWithDefault>;
-  expectTypeOf<inp>().toEqualTypeOf<string | util.Whatever>();
+  expectTypeOf<inp>().toEqualTypeOf<string | undefined>();
   type out = z.output<typeof stringWithDefault>;
   expectTypeOf<out>().toEqualTypeOf<string | undefined>();
 });
@@ -102,7 +101,7 @@ test("nested", () => {
     inner: "asdf",
   });
   type input = z.input<typeof outer>;
-  expectTypeOf<input>().toEqualTypeOf<{ inner: string | util.Whatever } | util.Whatever>();
+  expectTypeOf<input>().toEqualTypeOf<{ inner: string }>();
   type out = z.output<typeof outer>;
 
   expectTypeOf<out>().toEqualTypeOf<{ inner: string }>();

packages/zod/src/v4/core/schemas.ts

@@ -3315,11 +3315,8 @@ export interface $ZodCatchDef<T extends SomeType = $ZodType> extends $ZodTypeDef
 }
 
 export interface $ZodCatchInternals<T extends SomeType = $ZodType>
-  extends $ZodTypeInternals<core.output<T>, core.input<T> | util.Whatever> {
+  extends $ZodTypeInternals<core.output<T>, core.input<T>> {
   def: $ZodCatchDef<T>;
-  // qin: T["_zod"]["qin"];
-  // qout: T["_zod"]["qout"];
-
   optin: T["_zod"]["optin"];
   optout: T["_zod"]["optout"];
   isst: never;

play.ts

@@ -1,3 +1,5 @@
 import { z } from "zod";
 
 z;
+
+z.string().catch("asdf");