Improve types inside generic functions

colinhacks · Mar 6, 2023 · f9895ab · f9895ab
1 parent 4d016b7
commit f9895ab
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Showing 6 changed files with 48 additions and 38 deletions.
diff --git a/deno/lib/__tests__/generics.test.ts b/deno/lib/__tests__/generics.test.ts
@@ -8,21 +8,18 @@ import * as z from "../index.ts";
 test("generics", () => {
   async function stripOuter<TData extends z.ZodTypeAny>(
     schema: TData,
-    url: string
-  ): Promise<TData["_output"]> {
-    const zStrippedResponse = z
+    data: unknown
+  ) {
+    return z
       .object({
-        topLevelKey: schema,
+        nested: schema, // as z.ZodTypeAny,
       })
       .transform((data) => {
-        return data.topLevelKey;
-      });
-
-    return fetch(url)
-      .then((response) => response.json())
-      .then((data) => zStrippedResponse.parse(data));
+        return data.nested!;
+      })
+      .parse({ nested: data });
   }
 
-  const result = stripOuter(z.number(), "");
-  util.assertEqual<typeof result, Promise<number>>(true);
+  const result = stripOuter(z.object({ a: z.string() }), { a: "asdf" });
+  util.assertEqual<typeof result, Promise<{ a: string }>>(true);
 });
diff --git a/deno/lib/helpers/util.ts b/deno/lib/helpers/util.ts
@@ -5,6 +5,7 @@ export namespace util {
     ? true
     : false;
 
+  export type isAny<T> = 0 extends 1 & T ? true : false;
   export const assertEqual = <A, B>(val: AssertEqual<A, B>) => val;
   export function assertIs<T>(_arg: T): void {}
   export function assertNever(_x: never): never {
@@ -107,8 +108,14 @@ export namespace objectUtil {
     [k in keyof T]: undefined extends T[k] ? never : k;
   }[keyof T];
 
-  export type addQuestionMarks<T extends object> = Partial<T> &
-    Pick<T, requiredKeys<T>>;
+  // type alkjsdf = addQuestionMarks<{ a: any }>;
+
+  export type addQuestionMarks<
+    T extends object,
+    R extends keyof T = requiredKeys<T>
+    // O extends keyof T = optionalKeys<T>
+  > = Pick<T, R> & Partial<T>;
+  //  = { [k in O]?: T[k] } & { [k in R]: T[k] };
 
   export type identity<T> = T;
   export type flatten<T> = identity<{ [k in keyof T]: T[k] }>;

diff --git a/deno/lib/types.ts b/deno/lib/types.ts
@@ -2135,14 +2135,15 @@ export type objectOutputType<
   Shape extends ZodRawShape,
   Catchall extends ZodTypeAny,
   UnknownKeys extends UnknownKeysParam = UnknownKeysParam
-> = objectUtil.flatten<baseObjectOutputType<Shape>> &
+> = objectUtil.flatten<
+  objectUtil.addQuestionMarks<baseObjectOutputType<Shape>>
+> &
   CatchallOutput<Catchall> &
   PassthroughType<UnknownKeys>;
 
-export type baseObjectOutputType<Shape extends ZodRawShape> =
-  objectUtil.addQuestionMarks<{
-    [k in keyof Shape]: Shape[k]["_output"];
-  }>;
+export type baseObjectOutputType<Shape extends ZodRawShape> = {
+  [k in keyof Shape]: Shape[k]["_output"];
+};
 
 export type objectInputType<
   Shape extends ZodRawShape,

diff --git a/src/__tests__/generics.test.ts b/src/__tests__/generics.test.ts
@@ -7,21 +7,18 @@ import * as z from "../index";
 test("generics", () => {
   async function stripOuter<TData extends z.ZodTypeAny>(
     schema: TData,
-    url: string
-  ): Promise<TData["_output"]> {
-    const zStrippedResponse = z
+    data: unknown
+  ) {
+    return z
       .object({
-        topLevelKey: schema,
+        nested: schema, // as z.ZodTypeAny,
       })
       .transform((data) => {
-        return data.topLevelKey;
-      });
-
-    return fetch(url)
-      .then((response) => response.json())
-      .then((data) => zStrippedResponse.parse(data));
+        return data.nested!;
+      })
+      .parse({ nested: data });
   }
 
-  const result = stripOuter(z.number(), "");
-  util.assertEqual<typeof result, Promise<number>>(true);
+  const result = stripOuter(z.object({ a: z.string() }), { a: "asdf" });
+  util.assertEqual<typeof result, Promise<{ a: string }>>(true);
 });
diff --git a/src/helpers/util.ts b/src/helpers/util.ts
@@ -5,6 +5,7 @@ export namespace util {
     ? true
     : false;
 
+  export type isAny<T> = 0 extends 1 & T ? true : false;
   export const assertEqual = <A, B>(val: AssertEqual<A, B>) => val;
   export function assertIs<T>(_arg: T): void {}
   export function assertNever(_x: never): never {
@@ -107,8 +108,14 @@ export namespace objectUtil {
     [k in keyof T]: undefined extends T[k] ? never : k;
   }[keyof T];
 
-  export type addQuestionMarks<T extends object> = Partial<T> &
-    Pick<T, requiredKeys<T>>;
+  // type alkjsdf = addQuestionMarks<{ a: any }>;
+
+  export type addQuestionMarks<
+    T extends object,
+    R extends keyof T = requiredKeys<T>
+    // O extends keyof T = optionalKeys<T>
+  > = Pick<T, R> & Partial<T>;
+  //  = { [k in O]?: T[k] } & { [k in R]: T[k] };
 
   export type identity<T> = T;
   export type flatten<T> = identity<{ [k in keyof T]: T[k] }>;

diff --git a/src/types.ts b/src/types.ts
@@ -2135,14 +2135,15 @@ export type objectOutputType<
   Shape extends ZodRawShape,
   Catchall extends ZodTypeAny,
   UnknownKeys extends UnknownKeysParam = UnknownKeysParam
-> = objectUtil.flatten<baseObjectOutputType<Shape>> &
+> = objectUtil.flatten<
+  objectUtil.addQuestionMarks<baseObjectOutputType<Shape>>
+> &
   CatchallOutput<Catchall> &
   PassthroughType<UnknownKeys>;
 
-export type baseObjectOutputType<Shape extends ZodRawShape> =
-  objectUtil.addQuestionMarks<{
-    [k in keyof Shape]: Shape[k]["_output"];
-  }>;
+export type baseObjectOutputType<Shape extends ZodRawShape> = {
+  [k in keyof Shape]: Shape[k]["_output"];
+};
 
 export type objectInputType<
   Shape extends ZodRawShape,