From 2f800d4c1ab6827d8ab157eeabb0f5c5c01f83ed Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 28 Mar 2025 12:09:44 -0400
Subject: [PATCH] Revert "Revert "types: make `init` hooks types accurately
 reflect runtime behavior""

---
 test/types/middleware.preposttypes.test.ts | 146 +++++----------------
 test/types/schema.test.ts                  |  31 +++++
 types/index.d.ts                           |   1 +
 types/middlewares.d.ts                     |   2 +-
 4 files changed, 63 insertions(+), 117 deletions(-)

diff --git a/test/types/middleware.preposttypes.test.ts b/test/types/middleware.preposttypes.test.ts
index 052df875c0f..238059ee372 100644
--- a/test/types/middleware.preposttypes.test.ts
+++ b/test/types/middleware.preposttypes.test.ts
@@ -67,47 +67,6 @@ schema.pre('init', function() {
   expectType<HydratedDocument<IDocument>>(this);
 });
 
-schema.post('init', function(res) {
-  expectType<HydratedDocument<IDocument>>(this);
-  expectNotType<Query<any, any>>(res);
-});
-
-schema.pre('init', { document: true, query: false }, function() {
-  expectType<HydratedDocument<IDocument>>(this);
-});
-
-schema.post('init', { document: true, query: false }, function(res) {
-  expectType<HydratedDocument<IDocument>>(this);
-  expectNotType<Query<any, any>>(res);
-});
-
-schema.pre('init', { document: true, query: true }, function() {
-  expectType<HydratedDocument<IDocument>>(this);
-});
-
-schema.post('init', { document: true, query: true }, function(res) {
-  expectType<HydratedDocument<IDocument>>(this);
-  expectNotType<Query<any, any>>(res);
-});
-
-schema.pre('init', { document: false, query: true }, function() {
-  expectType<never>(this);
-});
-
-schema.post('init', { document: false, query: true }, function(res) {
-  expectType<never>(this);
-  expectNotType<Query<any, any>>(res);
-});
-
-schema.pre('init', { document: false, query: false }, function() {
-  expectType<never>(this);
-});
-
-schema.post('init', { document: false, query: false }, function(res) {
-  expectType<never>(this);
-  expectNotType<Query<any, any>>(res);
-});
-
 schema.pre('estimatedDocumentCount', function() {
   expectType<Query<any, any>>(this);
 });
@@ -693,51 +652,6 @@ schema.post('deleteOne', { document: false, query: false }, function(res) {
   expectNotType<Query<any, any>>(res);
 });
 
-schema.pre(['save', 'init'], function() {
-  expectType<HydratedDocument<IDocument>>(this);
-});
-
-schema.post(['save', 'init'], function(res) {
-  expectType<HydratedDocument<IDocument>>(this);
-  expectNotType<Query<any, any>>(res);
-});
-
-schema.pre(['save', 'init'], { document: true, query: false }, function() {
-  expectType<HydratedDocument<IDocument>>(this);
-});
-
-schema.post(['save', 'init'], { document: true, query: false }, function(res) {
-  expectType<HydratedDocument<IDocument>>(this);
-  expectNotType<Query<any, any>>(res);
-});
-
-schema.pre(['save', 'init'], { document: true, query: true }, function() {
-  expectType<HydratedDocument<IDocument>>(this);
-});
-
-schema.post(['save', 'init'], { document: true, query: true }, function(res) {
-  expectType<HydratedDocument<IDocument>>(this);
-  expectNotType<Query<any, any>>(res);
-});
-
-schema.pre(['save', 'init'], { document: false, query: true }, function() {
-  expectType<never>(this);
-});
-
-schema.post(['save', 'init'], { document: false, query: true }, function(res) {
-  expectType<never>(this);
-  expectNotType<Query<any, any>>(res);
-});
-
-schema.pre(['save', 'init'], { document: false, query: false }, function() {
-  expectType<never>(this);
-});
-
-schema.post(['save', 'init'], { document: false, query: false }, function(res) {
-  expectType<never>(this);
-  expectNotType<Query<any, any>>(res);
-});
-
 schema.pre(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany'], function() {
   expectType<Query<any, any>>(this);
 });
@@ -828,137 +742,137 @@ schema.post(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct
   expectNotType<Query<any, any>>(res);
 });
 
-schema.pre(['save', 'init', 'updateOne', 'deleteOne', 'validate'], function() {
+schema.pre(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'updateOne', 'deleteOne', 'validate'], function() {
   expectType<Query<any, any>|HydratedDocument<IDocument>>(this);
 });
 
-schema.post(['save', 'init', 'updateOne', 'deleteOne', 'validate'], function(res) {
+schema.post(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'updateOne', 'deleteOne', 'validate'], function(res) {
   expectType<Query<any, any>|HydratedDocument<IDocument>>(this);
   expectNotType<Query<any, any>>(res);
 });
 
-schema.pre(['save', 'init', 'updateOne', 'deleteOne', 'validate'], { document: false, query: true }, function() {
+schema.pre(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'updateOne', 'deleteOne', 'validate'], { document: false, query: true }, function() {
   expectType<Query<any, any>>(this);
 });
 
-schema.post(['save', 'init', 'updateOne', 'deleteOne', 'validate'], { document: false, query: true }, function(res) {
+schema.post(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'updateOne', 'deleteOne', 'validate'], { document: false, query: true }, function(res) {
   expectType<Query<any, any>>(this);
   expectNotType<Query<any, any>>(res);
 });
 
-schema.pre(['save', 'init', 'updateOne', 'deleteOne', 'validate'], { document: true, query: false }, function() {
+schema.pre(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'updateOne', 'deleteOne', 'validate'], { document: true, query: false }, function() {
   expectType<HydratedDocument<IDocument>>(this);
 });
 
-schema.post(['save', 'init', 'updateOne', 'deleteOne', 'validate'], { document: true, query: false }, function(res) {
+schema.post(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'updateOne', 'deleteOne', 'validate'], { document: true, query: false }, function(res) {
   expectType<HydratedDocument<IDocument>>(this);
   expectNotType<Query<any, any>>(res);
 });
 
-schema.pre(['save', 'init', 'updateOne', 'deleteOne', 'validate'], { document: true, query: true }, function() {
+schema.pre(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'updateOne', 'deleteOne', 'validate'], { document: true, query: true }, function() {
   expectType<Query<any, any>|HydratedDocument<IDocument>>(this);
 });
 
-schema.post(['save', 'init', 'updateOne', 'deleteOne', 'validate'], { document: true, query: true }, function(res) {
+schema.post(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'updateOne', 'deleteOne', 'validate'], { document: true, query: true }, function(res) {
   expectType<Query<any, any>|HydratedDocument<IDocument>>(this);
   expectNotType<Query<any, any>>(res);
 });
 
-schema.pre(['save', 'init', 'updateOne', 'deleteOne', 'validate'], { document: false, query: false }, function() {
+schema.pre(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'updateOne', 'deleteOne', 'validate'], { document: false, query: false }, function() {
   expectType<never>(this);
 });
 
-schema.post(['save', 'init', 'updateOne', 'deleteOne', 'validate'], { document: false, query: false }, function(res) {
+schema.post(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'updateOne', 'deleteOne', 'validate'], { document: false, query: false }, function(res) {
   expectType<never>(this);
   expectNotType<Query<any, any>>(res);
 });
 
-schema.pre(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'updateOne', 'deleteOne', 'validate'], function() {
+schema.pre(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'save', 'updateOne', 'deleteOne', 'validate'], function() {
   expectType<Query<any, any>|HydratedDocument<IDocument>>(this);
 });
 
-schema.post(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'updateOne', 'deleteOne', 'validate'], function(res) {
+schema.post(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'save', 'updateOne', 'deleteOne', 'validate'], function(res) {
   expectType<Query<any, any>|HydratedDocument<IDocument>>(this);
   expectNotType<Query<any, any>>(res);
 });
 
-schema.pre(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'updateOne', 'deleteOne', 'validate'], { document: false, query: true }, function() {
+schema.pre(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'save', 'updateOne', 'deleteOne', 'validate'], { document: false, query: true }, function() {
   expectType<Query<any, any>>(this);
 });
 
-schema.post(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'updateOne', 'deleteOne', 'validate'], { document: false, query: true }, function(res) {
+schema.post(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'save', 'updateOne', 'deleteOne', 'validate'], { document: false, query: true }, function(res) {
   expectType<Query<any, any>>(this);
   expectNotType<Query<any, any>>(res);
 });
 
-schema.pre(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'updateOne', 'deleteOne', 'validate'], { document: true, query: false }, function() {
+schema.pre(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'save', 'updateOne', 'deleteOne', 'validate'], { document: true, query: false }, function() {
   expectType<HydratedDocument<IDocument>>(this);
 });
 
-schema.post(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'updateOne', 'deleteOne', 'validate'], { document: true, query: false }, function(res) {
+schema.post(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'save', 'updateOne', 'deleteOne', 'validate'], { document: true, query: false }, function(res) {
   expectType<HydratedDocument<IDocument>>(this);
   expectNotType<Query<any, any>>(res);
 });
 
-schema.pre(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'updateOne', 'deleteOne', 'validate'], { document: true, query: true }, function() {
+schema.pre(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'save', 'updateOne', 'deleteOne', 'validate'], { document: true, query: true }, function() {
   expectType<Query<any, any>|HydratedDocument<IDocument>>(this);
 });
 
-schema.post(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'updateOne', 'deleteOne', 'validate'], { document: true, query: true }, function(res) {
+schema.post(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'save', 'updateOne', 'deleteOne', 'validate'], { document: true, query: true }, function(res) {
   expectType<Query<any, any>|HydratedDocument<IDocument>>(this);
   expectNotType<Query<any, any>>(res);
 });
 
-schema.pre(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'updateOne', 'deleteOne', 'validate'], { document: false, query: false }, function() {
+schema.pre(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'save', 'updateOne', 'deleteOne', 'validate'], { document: false, query: false }, function() {
   expectType<never>(this);
 });
 
-schema.post(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'updateOne', 'deleteOne', 'validate'], { document: false, query: false }, function(res) {
+schema.post(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'save', 'updateOne', 'deleteOne', 'validate'], { document: false, query: false }, function(res) {
   expectType<never>(this);
   expectNotType<Query<any, any>>(res);
 });
 
-schema.pre(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'save', 'init', 'updateOne', 'deleteOne', 'validate'], function() {
+schema.pre(['save', 'updateOne', 'deleteOne', 'validate'], function() {
   expectType<Query<any, any>|HydratedDocument<IDocument>>(this);
 });
 
-schema.post(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'save', 'init', 'updateOne', 'deleteOne', 'validate'], function(res) {
+schema.post(['save', 'updateOne', 'deleteOne', 'validate'], function(res) {
   expectType<Query<any, any>|HydratedDocument<IDocument>>(this);
   expectNotType<Query<any, any>>(res);
 });
 
-schema.pre(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'save', 'init', 'updateOne', 'deleteOne', 'validate'], { document: false, query: true }, function() {
+schema.pre(['save', 'updateOne', 'deleteOne', 'validate'], { document: false, query: true }, function() {
   expectType<Query<any, any>>(this);
 });
 
-schema.post(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'save', 'init', 'updateOne', 'deleteOne', 'validate'], { document: false, query: true }, function(res) {
+schema.post(['save', 'updateOne', 'deleteOne', 'validate'], { document: false, query: true }, function(res) {
   expectType<Query<any, any>>(this);
   expectNotType<Query<any, any>>(res);
 });
 
-schema.pre(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'save', 'init', 'updateOne', 'deleteOne', 'validate'], { document: true, query: false }, function() {
+schema.pre(['save', 'updateOne', 'deleteOne', 'validate'], { document: true, query: false }, function() {
   expectType<HydratedDocument<IDocument>>(this);
 });
 
-schema.post(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'save', 'init', 'updateOne', 'deleteOne', 'validate'], { document: true, query: false }, function(res) {
+schema.post(['save', 'updateOne', 'deleteOne', 'validate'], { document: true, query: false }, function(res) {
   expectType<HydratedDocument<IDocument>>(this);
   expectNotType<Query<any, any>>(res);
 });
 
-schema.pre(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'save', 'init', 'updateOne', 'deleteOne', 'validate'], { document: true, query: true }, function() {
+schema.pre(['save', 'updateOne', 'deleteOne', 'validate'], { document: true, query: true }, function() {
   expectType<Query<any, any>|HydratedDocument<IDocument>>(this);
 });
 
-schema.post(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'save', 'init', 'updateOne', 'deleteOne', 'validate'], { document: true, query: true }, function(res) {
+schema.post(['save', 'updateOne', 'deleteOne', 'validate'], { document: true, query: true }, function(res) {
   expectType<Query<any, any>|HydratedDocument<IDocument>>(this);
   expectNotType<Query<any, any>>(res);
 });
 
-schema.pre(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'save', 'init', 'updateOne', 'deleteOne', 'validate'], { document: false, query: false }, function() {
+schema.pre(['save', 'updateOne', 'deleteOne', 'validate'], { document: false, query: false }, function() {
   expectType<never>(this);
 });
 
-schema.post(['estimatedDocumentCount', 'countDocuments', 'deleteMany', 'distinct', 'find', 'findOne', 'findOneAndDelete', 'findOneAndReplace', 'findOneAndUpdate', 'replaceOne', 'updateMany', 'save', 'init', 'updateOne', 'deleteOne', 'validate'], { document: false, query: false }, function(res) {
+schema.post(['save', 'updateOne', 'deleteOne', 'validate'], { document: false, query: false }, function(res) {
   expectType<never>(this);
   expectNotType<Query<any, any>>(res);
 });
diff --git a/test/types/schema.test.ts b/test/types/schema.test.ts
index 20ecc9c0584..ee11e1f4e6f 100644
--- a/test/types/schema.test.ts
+++ b/test/types/schema.test.ts
@@ -1747,6 +1747,37 @@ async function schemaDouble() {
   expectType<Types.Double | null | undefined>(doc.balance);
 }
 
+function gh15301() {
+  interface IUser {
+    time: { hours: number, minutes: number }
+  }
+  const userSchema = new Schema<IUser>({
+    time: {
+      type: new Schema(
+        {
+          hours: { type: Number, required: true },
+          minutes: { type: Number, required: true }
+        },
+        { _id: false }
+      ),
+      required: true
+    }
+  });
+
+  const timeStringToObject = (time) => {
+    if (typeof time !== 'string') return time;
+    const [hours, minutes] = time.split(':');
+    return { hours: parseInt(hours), minutes: parseInt(minutes) };
+  };
+
+  userSchema.pre('init', function(rawDoc) {
+    expectType<IUser>(rawDoc);
+    if (typeof rawDoc.time === 'string') {
+      rawDoc.time = timeStringToObject(rawDoc.time);
+    }
+  });
+}
+
 function defaultReturnsUndefined() {
   const schema = new Schema<{ arr: number[] }>({
     arr: {
diff --git a/types/index.d.ts b/types/index.d.ts
index 1c3879d476f..ca951b4cf2d 100644
--- a/types/index.d.ts
+++ b/types/index.d.ts
@@ -436,6 +436,7 @@ declare module 'mongoose' {
     ): this;
     // this = Document
     pre<T = THydratedDocumentType>(method: 'save', fn: PreSaveMiddlewareFunction<T>): this;
+    pre<T = THydratedDocumentType, U = RawDocType>(method: 'init', fn: (this: T, doc: U) => void): this;
     pre<T = THydratedDocumentType>(method: MongooseDistinctDocumentMiddleware|MongooseDistinctDocumentMiddleware[], fn: PreMiddlewareFunction<T>): this;
     pre<T = THydratedDocumentType>(method: MongooseDistinctDocumentMiddleware|MongooseDistinctDocumentMiddleware[], options: SchemaPreOptions, fn: PreMiddlewareFunction<T>): this;
     pre<T = THydratedDocumentType>(
diff --git a/types/middlewares.d.ts b/types/middlewares.d.ts
index 8d380ed69d1..64d8ca620bb 100644
--- a/types/middlewares.d.ts
+++ b/types/middlewares.d.ts
@@ -3,7 +3,7 @@ declare module 'mongoose' {
 
   type MongooseQueryAndDocumentMiddleware = 'updateOne' | 'deleteOne';
 
-  type MongooseDistinctDocumentMiddleware = 'save' | 'init' | 'validate';
+  type MongooseDistinctDocumentMiddleware = 'save' | 'validate';
   type MongooseDocumentMiddleware = MongooseDistinctDocumentMiddleware | MongooseQueryAndDocumentMiddleware;
 
   type MongooseRawResultQueryMiddleware = 'findOneAndUpdate' | 'findOneAndReplace' | 'findOneAndDelete';