From 2667312c664da2779f65477b606398ca2c7a376c Mon Sep 17 00:00:00 2001
From: Orgad Shaneh <orgad.shaneh@audiocodes.com>
Date: Tue, 4 Jul 2023 08:34:54 +0300
Subject: [PATCH] Avoid using Omit in HydratedDocument when not needed

See https://github.com/microsoft/TypeScript/issues/39556 and many other
related issues.

Fixes #13529.
---
 test/types/models.test.ts | 18 ++++++++++++++++++
 types/index.d.ts          |  2 +-
 types/utility.d.ts        |  9 ++++-----
 3 files changed, 23 insertions(+), 6 deletions(-)

diff --git a/test/types/models.test.ts b/test/types/models.test.ts
index 3f95d61e271..99f311540bc 100644
--- a/test/types/models.test.ts
+++ b/test/types/models.test.ts
@@ -622,3 +622,21 @@ function gh13206() {
     expectType<ChangeStreamInsertDocument<ITest>>(change);
   });
 }
+
+function gh13529() {
+  interface ResourceDoc {
+    foo: string;
+  }
+
+  type ResourceIdT<ResourceIdField extends string> = {
+    [key in ResourceIdField]: string;
+  };
+  type ResourceDocWithId<ResourceIdField extends string> = ResourceDoc & ResourceIdT<ResourceIdField>;
+
+  function test<
+    ResourceType extends string,
+    DocT extends ResourceDocWithId<`${ResourceType}Id`>>(dbModel: Model<DocT>) {
+    const resourceDoc = new dbModel();
+    resourceDoc.foo = 'bar';
+  }
+}
diff --git a/types/index.d.ts b/types/index.d.ts
index 62d7a2ee5c2..794f184b80a 100644
--- a/types/index.d.ts
+++ b/types/index.d.ts
@@ -141,7 +141,7 @@ declare module 'mongoose' {
   > = IfAny<
     DocType,
     any,
-    Document<unknown, TQueryHelpers, DocType> & MergeType<
+    Document<unknown, TQueryHelpers, DocType> & MergeUnlessEmpty<
       Require_id<DocType>,
       TOverrides extends Record<string, never> ?
         {} :
diff --git a/types/utility.d.ts b/types/utility.d.ts
index 69fe73a7be3..2f61efa17fb 100644
--- a/types/utility.d.ts
+++ b/types/utility.d.ts
@@ -6,13 +6,12 @@ declare module 'mongoose' {
     U :
     T extends ReadonlyArray<infer U> ? U : T;
 
+  type MergeType<A, B> = Omit<A, keyof B> & B;
+  type MergeUnlessEmpty<A, B> = keyof B extends never ? A : Omit<A, keyof B> & B;
+
   type UnpackedIntersection<T, U> = T extends null ? null : T extends (infer A)[]
     ? (Omit<A, keyof U> & U)[]
-    : keyof U extends never
-      ? T
-      : Omit<T, keyof U> & U;
-
-  type MergeType<A, B> = Omit<A, keyof B> & B;
+    : MergeUnlessEmpty<T, U>;
 
   /**
    * @summary Converts Unions to one record "object".