From 0170e3c9467dec5ce53d03fc8ee0edeec40bd02e Mon Sep 17 00:00:00 2001
From: Colin McDonnell <colinmcd@alum.mit.edu>
Date: Sun, 27 Sep 2020 15:59:05 -0700
Subject: [PATCH] Fixed explicit undefined values for optional keys. Fixes #161

---
 README.md                    |  1 +
 src/__tests__/object.test.ts | 13 +++++++++++++
 src/parser.ts                | 21 ++++++++++++++++++--
 src/playground.ts            | 37 ++++++++++++++++++++++++------------
 4 files changed, 58 insertions(+), 14 deletions(-)

diff --git a/README.md b/README.md
index 5833cb688..fa2e8a48d 100644
--- a/README.md
+++ b/README.md
@@ -66,6 +66,7 @@ Some other great aspects:
 - Immutability: methods (i.e. `.optional()` return a new instance
 - Concise, chainable interface
 - Functional approach: [parse, don't validate](https://lexi-lambda.github.io/blog/2019/11/05/parse-don-t-validate/)
+- Works with plain JavaScript too! You don't need to use TypeScript.
 
 # Sponsorship
 
diff --git a/src/__tests__/object.test.ts b/src/__tests__/object.test.ts
index 4b21dee1b..cfe8c4234 100644
--- a/src/__tests__/object.test.ts
+++ b/src/__tests__/object.test.ts
@@ -236,3 +236,16 @@ test('catchall overrides strict', () => {
     asdf: 1234,
   });
 });
+
+test('test that optional keys are unset', async () => {
+  const SNamedEntity = z.object({
+    id: z.string(),
+    set: z.string().optional(),
+    unset: z.string().optional(),
+  });
+  const result = await SNamedEntity.parse({
+    id: 'asdf',
+    set: undefined,
+  });
+  expect(Object.keys(result)).toEqual(['id', 'set']);
+});
diff --git a/src/parser.ts b/src/parser.ts
index a8df449b7..fb30bd7b7 100644
--- a/src/parser.ts
+++ b/src/parser.ts
@@ -367,19 +367,36 @@ export const ZodParser = (schema: z.ZodType<any>) => (
 
       for (const key of shapeKeys) {
         const keyValidator = shapeKeys.includes(key)
-          ? def.shape()[key]
+          ? shape[key]
           : !(def.catchall instanceof ZodNever)
           ? def.catchall
           : undefined;
 
         if (!keyValidator) continue;
 
+        // check if schema and value are both optional
+        try {
+          keyValidator.parse(undefined, {
+            ...params,
+            path: [...params.path, key],
+          });
+
+          // const keyDataType = getParsedType(data[key]);
+          if (!Object.keys(data).includes(key)) {
+            // schema is optional
+            // data is undefined
+            // don't explicity add undefined to outut
+            continue;
+          }
+        } catch (err) {}
+
         objectPromises[key] = new PseudoPromise().then(() => {
           try {
-            return keyValidator.parse(data[key], {
+            const parsedValue = keyValidator.parse(data[key], {
               ...params,
               path: [...params.path, key],
             });
+            return parsedValue;
           } catch (err) {
             if (err instanceof ZodError) {
               const zerr: ZodError = err;
diff --git a/src/playground.ts b/src/playground.ts
index 2ae1e30b0..99994bd8f 100644
--- a/src/playground.ts
+++ b/src/playground.ts
@@ -1,17 +1,30 @@
 import * as z from '.';
-// import { Scalars } from './helpers/primitive';
 
-const obj = z.object({
-  primitiveTuple: z.tuple([z.string(), z.number()]),
-  nonprimitiveTuple: z.tuple([z.string(), z.number().array()]),
-});
+const run = async () => {
+  const SNamedEntity = z.object({
+    id: z.string(),
+    set: z.string().optional(),
+    unset: z.string().optional(),
+  });
+  const result = await SNamedEntity.parse({
+    id: 'asdf',
+    set: undefined,
+  });
+  console.log(result);
+  console.log(Object.keys(result));
+};
+run();
 
-type obj = z.infer<typeof obj>;
+// export const T = z.object({
+//   test: z.string().optional(),
+// });
 
-const prim = obj.primitives();
-console.log(prim.shape);
-const nonprim = obj.nonprimitives();
-console.log(nonprim.shape);
-// .primitives();
+// console.log(T.safeParse({}));
 
-// type t1 = [[string, number]] extends [Scalars] ? true : false;
+// const r = T.safeParse({});
+
+// if (r.success) {
+//   console.log(JSON.stringify(r.data));
+// }
+
+// console.log(JSON.stringify({ test: undefined, test2: undefined }, null, 2));