From b3e25b964dcc08714873c6798ae24aa2a6ea03a0 Mon Sep 17 00:00:00 2001
From: Colin McDonnell <colinmcd94@gmail.com>
Date: Fri, 22 Mar 2024 15:40:34 -0700
Subject: [PATCH] Fix #2196

---
 deno/lib/__tests__/generics.test.ts | 18 ++++++++++++++++++
 deno/lib/helpers/util.ts            | 11 ++++++-----
 playground.ts                       |  4 ++++
 src/__tests__/generics.test.ts      | 18 ++++++++++++++++++
 src/helpers/util.ts                 | 11 ++++++-----
 5 files changed, 52 insertions(+), 10 deletions(-)

diff --git a/deno/lib/__tests__/generics.test.ts b/deno/lib/__tests__/generics.test.ts
index 388e147e7..d0a2ec025 100644
--- a/deno/lib/__tests__/generics.test.ts
+++ b/deno/lib/__tests__/generics.test.ts
@@ -23,3 +23,21 @@ test("generics", () => {
   const result = stripOuter(z.object({ a: z.string() }), { a: "asdf" });
   util.assertEqual<typeof result, Promise<{ a: string }>>(true);
 });
+
+test("assignability", () => {
+  const createSchemaAndParse = <K extends string, VS extends z.ZodString>(
+    key: K,
+    valueSchema: VS,
+    data: unknown
+  ) => {
+    const schema = z.object({
+      [key]: valueSchema,
+    });
+    const parsed = schema.parse(data);
+    type aldsjkf = z.infer<z.ZodObject<{ [k in K]: VS }>>;
+    const inferred: z.infer<z.ZodObject<{ [k in K]: VS }>> = parsed;
+    // this line errors in 3.21.2
+    return inferred;
+  };
+  createSchemaAndParse("foo", z.string(), { foo: "" });
+});
diff --git a/deno/lib/helpers/util.ts b/deno/lib/helpers/util.ts
index 6aa6f5dde..320bf051b 100644
--- a/deno/lib/helpers/util.ts
+++ b/deno/lib/helpers/util.ts
@@ -100,9 +100,9 @@ export namespace objectUtil {
     [k in Exclude<keyof U, keyof V>]: U[k];
   } & V;
 
-  // type optionalKeys<T extends object> = {
-  //   [k in keyof T]: undefined extends T[k] ? k : never;
-  // }[keyof T];
+  type optionalKeys<T extends object> = {
+    [k in keyof T]: undefined extends T[k] ? k : never;
+  }[keyof T];
 
   type requiredKeys<T extends object> = {
     [k in keyof T]: undefined extends T[k] ? never : k;
@@ -110,8 +110,9 @@ export namespace objectUtil {
 
   export type addQuestionMarks<
     T extends object,
-    R extends keyof T = requiredKeys<T>
-  > = Pick<Required<T>, R> & Omit<Partial<T>, R> & { [k in keyof T]?: unknown };
+    R extends keyof T = requiredKeys<T>,
+    O extends keyof T = optionalKeys<T>
+  > = Pick<T, R> & Partial<Pick<T, O>> & { [k in keyof T]?: unknown };
 
   export type identity<T> = T;
   export type flatten<T> = identity<{ [k in keyof T]: T[k] }>;
diff --git a/playground.ts b/playground.ts
index 4e01473b6..152125fe5 100644
--- a/playground.ts
+++ b/playground.ts
@@ -1,3 +1,7 @@
 import { z } from "./src";
 
 z;
+
+const schema = z.object({ name: z.string() }).catchall(z.string());
+
+type schema = z.input<typeof schema>;
diff --git a/src/__tests__/generics.test.ts b/src/__tests__/generics.test.ts
index 56460f26f..8415f1044 100644
--- a/src/__tests__/generics.test.ts
+++ b/src/__tests__/generics.test.ts
@@ -22,3 +22,21 @@ test("generics", () => {
   const result = stripOuter(z.object({ a: z.string() }), { a: "asdf" });
   util.assertEqual<typeof result, Promise<{ a: string }>>(true);
 });
+
+test("assignability", () => {
+  const createSchemaAndParse = <K extends string, VS extends z.ZodString>(
+    key: K,
+    valueSchema: VS,
+    data: unknown
+  ) => {
+    const schema = z.object({
+      [key]: valueSchema,
+    });
+    const parsed = schema.parse(data);
+    type aldsjkf = z.infer<z.ZodObject<{ [k in K]: VS }>>;
+    const inferred: z.infer<z.ZodObject<{ [k in K]: VS }>> = parsed;
+    // this line errors in 3.21.2
+    return inferred;
+  };
+  createSchemaAndParse("foo", z.string(), { foo: "" });
+});
diff --git a/src/helpers/util.ts b/src/helpers/util.ts
index 6aa6f5dde..320bf051b 100644
--- a/src/helpers/util.ts
+++ b/src/helpers/util.ts
@@ -100,9 +100,9 @@ export namespace objectUtil {
     [k in Exclude<keyof U, keyof V>]: U[k];
   } & V;
 
-  // type optionalKeys<T extends object> = {
-  //   [k in keyof T]: undefined extends T[k] ? k : never;
-  // }[keyof T];
+  type optionalKeys<T extends object> = {
+    [k in keyof T]: undefined extends T[k] ? k : never;
+  }[keyof T];
 
   type requiredKeys<T extends object> = {
     [k in keyof T]: undefined extends T[k] ? never : k;
@@ -110,8 +110,9 @@ export namespace objectUtil {
 
   export type addQuestionMarks<
     T extends object,
-    R extends keyof T = requiredKeys<T>
-  > = Pick<Required<T>, R> & Omit<Partial<T>, R> & { [k in keyof T]?: unknown };
+    R extends keyof T = requiredKeys<T>,
+    O extends keyof T = optionalKeys<T>
+  > = Pick<T, R> & Partial<Pick<T, O>> & { [k in keyof T]?: unknown };
 
   export type identity<T> = T;
   export type flatten<T> = identity<{ [k in keyof T]: T[k] }>;