Update to send previous value as well

Author: HLXII

src/ig-template/features/settings/Setting.ts

@@ -15,7 +15,7 @@ export abstract class Setting {
 
     requirement: Requirement;
 
-    protected _onChange = new SimpleEventDispatcher<SettingsValue>();
+    protected _onChange = new SimpleEventDispatcher<SettingsValue[]>();
 
     protected constructor(id: SettingId, displayName: string, options: SettingOption[], defaultValue: SettingsValue, requirement: Requirement = new NoRequirement()) {
         this.id = id;
@@ -31,7 +31,7 @@ export abstract class Setting {
    /**
      * Emitted whenever the setting is changed.
      */
-    public get onChange(): ISimpleEvent<SettingsValue> {
+    public get onChange(): ISimpleEvent<SettingsValue[]> {
         return this._onChange.asEvent();
     }
 
@@ -40,8 +40,9 @@ export abstract class Setting {
             return;
         }
         if (this.validValue(value)) {
+            const prevValue = this.value;
             this.value = value;
-            this._onChange.dispatch(value);
+            this._onChange.dispatch([prevValue, value]);
         } else {
             console.warn(`${value} is not a valid value for setting ${this.id}. It could be that the option is not yet unlocked.`);
         }

tests/unit/ig-template/features/settings/Settings.spec.ts

@@ -63,17 +63,18 @@ describe('Settings', () => {
     });
 
     test('test change event', () => {
-        expect.assertions(3);
+        expect.assertions(4);
 
         const setting = settings.getSetting(id);
-        setting?.onChange.subscribe(value => {
-            expect(value).toBe(2);
+        setting?.onChange.subscribe(([prevValue, value]) => {
+            expect(prevValue).toBe(2);
+            expect(value).toBe(3);
         });
 
-        settings.setSetting(id, 2);
+        settings.setSetting(id, 3);
 
         expect(setting).toBeDefined();
-        expect(setting?.value).toBe(2);
+        expect(setting?.value).toBe(3);
     });
 
     test('save empty', () => {