From 0738f368ca9529eebd84a6ea56d94d5ff7d257db Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 11 Jan 2021 15:00:18 -0500
Subject: [PATCH] fix: add back fix for #8883 for 6.0

---
 lib/schema.js | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/lib/schema.js b/lib/schema.js
index 9c462c1f914..64a35286c06 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -938,6 +938,11 @@ Schema.prototype.interpretAsType = function(path, obj, options) {
         if (options.hasOwnProperty('strict')) {
           childSchemaOptions.strict = options.strict;
         }
+        if (this._userProvidedOptions.hasOwnProperty('_id')) {
+          childSchemaOptions._id = this._userProvidedOptions._id;
+        } else if (Schema.Types.DocumentArray.defaultOptions._id != null) {
+          childSchemaOptions._id = Schema.Types.DocumentArray.defaultOptions._id;
+        }
         const childSchema = new Schema(cast, childSchemaOptions);
         childSchema.$implicitlyCreated = true;
         return new MongooseTypes.DocumentArray(path, childSchema, obj);