feat: zod v4 migration

Author: JeanMeijer

packages/temporal-zod/package.json

@@ -30,7 +30,7 @@
     "temporal-polyfill": "^0.3.0",
     "typescript": "^5.8.2",
     "vitest": "^3.1.1",
-    "zod": "^3.24.2"
+    "zod": "^4"
   },
   "main": "dist/index.js",
   "types": "dist/index.d.ts",
@@ -56,6 +56,6 @@
   },
   "peerDependencies": {
     "temporal-polyfill": "^0.2 || ^0.3",
-    "zod": "^3.24.1"
+    "zod": "^4"
   }
 }

packages/temporal-zod/src/base/instant.ts

@@ -10,18 +10,14 @@ const validators = temporalValidators(Instant);
 /**
  * Validates or coerces a string or Date to a {@link Temporal.Instant}.
  */
-export const zInstant: z.ZodType<
-  Temporal.Instant,
-  z.ZodTypeDef,
-  Temporal.Instant | string | Date
-> = z.union([
+export const zInstant = z.union([
   validators.coerce,
   z
     .date()
     .transform((value) =>
       Temporal.Instant.fromEpochMilliseconds(value.getTime()),
     ),
-]);
+]) as z.ZodType<Temporal.Instant>;
 
 /**
  * Validates that the value is an instance of {@link Temporal.Instant}.

packages/temporal-zod/src/base/temporalValidator.ts

@@ -12,11 +12,7 @@ export type ZodTemporal<
   TClass extends typeof Class & {
     from: (arg: string) => InstanceType<TClass>;
   },
-> = z.ZodType<
-  InstanceType<TClass>,
-  z.ZodTypeDef,
-  InstanceType<TClass> | string
->;
+> = z.ZodType<InstanceType<TClass>>;
 
 /**
  * Creates Zod validators for a Temporal class.
@@ -40,9 +36,10 @@ export function temporalValidators<
         try {
           return cls.from(value);
         } catch (error: unknown) {
-          ctx.addIssue({
-            code: z.ZodIssueCode.invalid_date,
+          ctx.issues.push({
+            code: "custom",
             message: `Invalid ${cls.name}: ${(error as { message?: string }).message ?? "unknown error"}`,
+            input: value,
           });
           return z.NEVER;
         }