ManyModelRelation: add cloneReduceToOne method

package.json

@@ -1,6 +1,6 @@
 {
   "name": "wms-core",
-  "version": "0.10.1",
+  "version": "0.10.2",
   "description": "Node web framework",
   "repository": "git@gitlab.com:ArisuOngaku/wms-core.git",
   "author": "Alice Gaudon <alice@gaudon.pro>",

src/auth/models/User.ts

@@ -22,7 +22,7 @@ export default class User extends Model {
         foreignKey: 'user_id'
     });
 
-    public readonly mainEmail = this.emails.clone().constraint(q => q.where('main', true));
+    public readonly mainEmail = this.emails.cloneReduceToOne().constraint(q => q.where('main', true));
 
     protected init(): void {
         this.addProperty<string>('name', new Validator().acceptUndefined().between(3, 64));

src/db/ModelRelation.ts

@@ -86,6 +86,10 @@ export class ManyModelRelation<S extends Model, O extends Model> extends ModelRe
         return new ManyModelRelation<S, O>(this.model, this.foreignModelClass, this.dbProperties);
     }
 
+    public cloneReduceToOne(): OneModelRelation<S, O> {
+        return new OneModelRelation<S, O>(this.model, this.foreignModelClass, this.dbProperties);
+    }
+
     public getModelID(): any {
         return this.model[this.dbProperties.localKey];
     }