feat(typings): model.count with group by (#10763)

types/lib/model.d.ts

@@ -527,6 +527,18 @@ export interface CountOptions extends Logging, Transactionable, Filterable, Proj
   col?: string;
 }
 
+/**
+ * Options for Model.count when GROUP BY is used
+ */
+export interface CountWithOptions extends CountOptions {
+  /**
+   * GROUP BY in sql
+   * Used in conjunction with `attributes`.
+   * @see Projectable
+   */
+  group: GroupOption;
+}
+
 export interface FindAndCountOptions extends CountOptions, FindOptions {}
 
 /**
@@ -1743,6 +1755,11 @@ export abstract class Model<T = any, T2 = any> extends Hooks {
     options?: AggregateOptions<T>
   ): Promise<T>;
 
+  /**
+   * Count number of records if group by is used
+   */
+  public static count(options: CountWithOptions): Promise<{ [key: string]: number }>;
+
   /**
    * Count the number of records matching the provided where clause.
    *

types/test/count.ts

@@ -0,0 +1,7 @@
+import { Model, Promise } from 'sequelize';
+
+class MyModel extends Model {}
+
+const grouped: Promise<{ [key: string]: number }> = MyModel.count({ group: 'tag' });
+const counted: Promise<number> = MyModel.count();
+const countedDistinct: Promise<number> = MyModel.count({ col: 'tag', distinct: true });