From 0ee889391bb82fe117d1209c75c38e444e068ddf Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 23 Nov 2022 16:08:21 -0500
Subject: [PATCH 1/2] fix(types): correctly infer ReadonlyArray types in schema
 definitions

Fix #12611
---
 test/types/schema.test.ts  | 19 ++++++++++++++
 types/inferschematype.d.ts | 53 +++++++++++++++++++-------------------
 2 files changed, 46 insertions(+), 26 deletions(-)

diff --git a/test/types/schema.test.ts b/test/types/schema.test.ts
index 7bd00a8d4b8..2a9f66b4d63 100644
--- a/test/types/schema.test.ts
+++ b/test/types/schema.test.ts
@@ -938,3 +938,22 @@ function gh12590() {
   });
 
 }
+
+function gh12611() {
+  const reusableFields = {
+    description: { type: String, required: true },
+    skills: { type: [Schema.Types.ObjectId], ref: "Skill", default: [] }
+  } as const;
+  
+  const firstSchema = new Schema({
+    ...reusableFields,
+    anotherField: String
+  });
+  
+  type Props = InferSchemaType<typeof firstSchema>;
+  expectType<{
+    description: string;
+    skills: Types.ObjectId[];
+    anotherField?: string;
+  }>({} as Props);
+}
diff --git a/types/inferschematype.d.ts b/types/inferschematype.d.ts
index e8c345fc707..c4dc62f7502 100644
--- a/types/inferschematype.d.ts
+++ b/types/inferschematype.d.ts
@@ -161,29 +161,30 @@ type PathEnumOrString<T extends SchemaTypeOptions<string>['enum']> = T extends (
 type ResolvePathType<PathValueType, Options extends SchemaTypeOptions<PathValueType> = {}, TypeKey extends TypeKeyBaseType = DefaultTypeKey> =
   PathValueType extends Schema ? InferSchemaType<PathValueType> :
     PathValueType extends (infer Item)[] ? IfEquals<Item, never, any[], Item extends Schema ? Types.DocumentArray<ObtainDocumentPathType<Item, TypeKey>> : ObtainDocumentPathType<Item, TypeKey>[]> :
-      PathValueType extends StringSchemaDefinition ? PathEnumOrString<Options['enum']> :
-        IfEquals<PathValueType, Schema.Types.String> extends true ? PathEnumOrString<Options['enum']> :
-          IfEquals<PathValueType, String> extends true ? PathEnumOrString<Options['enum']> :
-            PathValueType extends NumberSchemaDefinition ? Options['enum'] extends ReadonlyArray<any> ? Options['enum'][number] : number :
-              IfEquals<PathValueType, Schema.Types.Number> extends true ? number :
-                PathValueType extends DateSchemaDefinition ? Date :
-                  IfEquals<PathValueType, Schema.Types.Date> extends true ? Date :
-                    PathValueType extends typeof Buffer | 'buffer' | 'Buffer' | typeof Schema.Types.Buffer ? Buffer :
-                      PathValueType extends BooleanSchemaDefinition ? boolean :
-                        IfEquals<PathValueType, Schema.Types.Boolean> extends true ? boolean :
-                          PathValueType extends ObjectIdSchemaDefinition ? Types.ObjectId :
-                            IfEquals<PathValueType, Types.ObjectId> extends true ? Types.ObjectId :
-                              IfEquals<PathValueType, Schema.Types.ObjectId> extends true ? Types.ObjectId :
-                                PathValueType extends 'decimal128' | 'Decimal128' | typeof Schema.Types.Decimal128 ? Types.Decimal128 :
-                                  IfEquals<PathValueType, Schema.Types.Decimal128> extends true ? Types.Decimal128 :
-                                    IfEquals<PathValueType, Types.Decimal128> extends true ? Types.Decimal128 :
-                                      PathValueType extends 'uuid' | 'UUID' | typeof Schema.Types.UUID ? Buffer :
-                                        IfEquals<PathValueType, Schema.Types.UUID> extends true ? Buffer :
-                                          PathValueType extends MapConstructor ? Map<string, ResolvePathType<Options['of']>> :
-                                            PathValueType extends ArrayConstructor ? any[] :
-                                              PathValueType extends typeof Schema.Types.Mixed ? any:
-                                                IfEquals<PathValueType, ObjectConstructor> extends true ? any:
-                                                  IfEquals<PathValueType, {}> extends true ? any:
-                                                    PathValueType extends typeof SchemaType ? PathValueType['prototype'] :
-                                                      PathValueType extends Record<string, any> ? ObtainDocumentType<PathValueType, any, TypeKey> :
-                                                        unknown;
+      PathValueType extends ReadonlyArray<infer Item> ? IfEquals<Item, never, any[], Item extends Schema ? Types.DocumentArray<ObtainDocumentPathType<Item, TypeKey>> : ObtainDocumentPathType<Item, TypeKey>[]> :
+        PathValueType extends StringSchemaDefinition ? PathEnumOrString<Options['enum']> :
+          IfEquals<PathValueType, Schema.Types.String> extends true ? PathEnumOrString<Options['enum']> :
+            IfEquals<PathValueType, String> extends true ? PathEnumOrString<Options['enum']> :
+              PathValueType extends NumberSchemaDefinition ? Options['enum'] extends ReadonlyArray<any> ? Options['enum'][number] : number :
+                IfEquals<PathValueType, Schema.Types.Number> extends true ? number :
+                  PathValueType extends DateSchemaDefinition ? Date :
+                    IfEquals<PathValueType, Schema.Types.Date> extends true ? Date :
+                      PathValueType extends typeof Buffer | 'buffer' | 'Buffer' | typeof Schema.Types.Buffer ? Buffer :
+                        PathValueType extends BooleanSchemaDefinition ? boolean :
+                          IfEquals<PathValueType, Schema.Types.Boolean> extends true ? boolean :
+                            PathValueType extends ObjectIdSchemaDefinition ? Types.ObjectId :
+                              IfEquals<PathValueType, Types.ObjectId> extends true ? Types.ObjectId :
+                                IfEquals<PathValueType, Schema.Types.ObjectId> extends true ? Types.ObjectId :
+                                  PathValueType extends 'decimal128' | 'Decimal128' | typeof Schema.Types.Decimal128 ? Types.Decimal128 :
+                                    IfEquals<PathValueType, Schema.Types.Decimal128> extends true ? Types.Decimal128 :
+                                      IfEquals<PathValueType, Types.Decimal128> extends true ? Types.Decimal128 :
+                                        PathValueType extends 'uuid' | 'UUID' | typeof Schema.Types.UUID ? Buffer :
+                                          IfEquals<PathValueType, Schema.Types.UUID> extends true ? Buffer :
+                                            PathValueType extends MapConstructor ? Map<string, ResolvePathType<Options['of']>> :
+                                              PathValueType extends ArrayConstructor ? any[] :
+                                                PathValueType extends typeof Schema.Types.Mixed ? any:
+                                                  IfEquals<PathValueType, ObjectConstructor> extends true ? any:
+                                                    IfEquals<PathValueType, {}> extends true ? any:
+                                                      PathValueType extends typeof SchemaType ? PathValueType['prototype'] :
+                                                        PathValueType extends Record<string, any> ? ObtainDocumentType<PathValueType, any, TypeKey> :
+                                                          unknown;

From 12706ebdd0ea039103636ef9ea4d25f7a0282f00 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 23 Nov 2022 16:14:05 -0500
Subject: [PATCH 2/2] style: fix lint

---
 test/types/schema.test.ts | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/test/types/schema.test.ts b/test/types/schema.test.ts
index 2a9f66b4d63..a531247e183 100644
--- a/test/types/schema.test.ts
+++ b/test/types/schema.test.ts
@@ -942,14 +942,14 @@ function gh12590() {
 function gh12611() {
   const reusableFields = {
     description: { type: String, required: true },
-    skills: { type: [Schema.Types.ObjectId], ref: "Skill", default: [] }
+    skills: { type: [Schema.Types.ObjectId], ref: 'Skill', default: [] }
   } as const;
-  
+
   const firstSchema = new Schema({
     ...reusableFields,
     anotherField: String
   });
-  
+
   type Props = InferSchemaType<typeof firstSchema>;
   expectType<{
     description: string;