Merge pull request #9680 from orgads/aggregate

fix(index.d.ts): Fix return type of Model#aggregate()

Author: vkarpov15

index.d.ts

@@ -578,8 +578,8 @@ declare module "mongoose" {
   interface Model<T extends Document> extends NodeJS.EventEmitter {
     new(doc?: any): T;
 
-    aggregate<R>(pipeline?: any[]): Aggregate<Array<R>>;
-    aggregate<R>(pipeline: any[], cb: Function): Promise<Array<R>>;
+    aggregate<R = any>(pipeline?: any[]): Aggregate<Array<R>>;
+    aggregate<R = any>(pipeline: any[], cb: Function): Promise<Array<R>>;
 
     /** Base Mongoose instance the model uses. */
     base: typeof mongoose;

test/typescript/models.ts

@@ -21,3 +21,5 @@ const ExpiresSchema = new Schema({
     expires: 3600,
   },
 });
+
+const aggregated: Promise<Document> = Test.aggregate([]).then(res => res[0]);