adds ClientSession to SaveOptions mongoose (#28880)

* adds session to SaveOptions

* removes redundant create method

types/mongoose/index.d.ts

@@ -2705,6 +2705,7 @@ declare module "mongoose" {
      * Triggers the save() hook.
      */
     create(docs: any[], callback?: (err: any, res: T[]) => void): Promise<T[]>;
+    create(docs: any[], options?: SaveOptions, callback?: (err: any, res: T[]) => void): Promise<T[]>;
     create(...docs: any[]): Promise<T>;
     create(...docsWithCallback: any[]): Promise<T>;
 
@@ -2992,6 +2993,7 @@ declare module "mongoose" {
   interface SaveOptions {
     safe?: boolean | WriteConcern;
     validateBeforeSave?: boolean;
+    session?: ClientSession;
   }
 
   interface WriteConcern {
@@ -3034,7 +3036,7 @@ declare module "mongoose" {
   interface ModelOptions {
     session?: ClientSession | null;
   }
-  
+
   interface ModelFindByIdAndUpdateOptions extends ModelOptions {
     /** true to return the modified document rather than the original. defaults to false */
     new?: boolean;

types/mongoose/mongoose-tests.ts

@@ -1960,4 +1960,30 @@ db.createCollection('users').
   ]).session(session).exec()).
   then((res: any) => {
     session.commitTransaction();
-  });
+  });
+
+/** https://mongoosejs.com/docs/transactions.html */
+
+const Customer = db.model('Customer', new mongoose.Schema({ name: String }));
+
+db.createCollection('customers').
+  then(() => db.startSession()).
+  then(_session => {
+    session = _session;
+    // Start a transaction
+    session.startTransaction();
+    // This `create()` is part of the transaction because of the `session`
+    // option.
+    return Customer.create([{ name: 'Test' }], { session: session });
+  }).
+  // Transactions execute in isolation, so unless you pass a `session`
+  // to `findOne()` you won't see the document until the transaction
+  // is committed.
+  then((customer: mongoose.Document[]) => Customer.findOne({ name: 'Test' }).exec()).
+  // This `findOne()` will return the doc, because passing the `session`
+  // means this `findOne()` will run as part of the transaction.
+  then(() => Customer.findOne({ name: 'Test' }).session(session).exec()).
+  // Once the transaction is committed, the write operation becomes
+  // visible outside of the transaction.
+  then(() => session.commitTransaction()).
+  then(() => Customer.findOne({ name: 'Test' }).exec())