fix(signal-slice): typing for Subject with union type (#169)

ngxtension · Nov 21, 2023 · 746c0fc · 746c0fc
1 parent e4ffaee
commit 746c0fc
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Showing 2 changed files with 36 additions and 9 deletions.
diff --git a/libs/ngxtension/signal-slice/src/signal-slice.spec.ts b/libs/ngxtension/signal-slice/src/signal-slice.spec.ts
@@ -10,6 +10,7 @@ describe(signalSlice.name, () => {
 			lastName: 'morony',
 		},
 		age: 30,
+		powerLevel: 50 as number | null,
 		likes: ['angular', 'typescript'],
 	};
 
@@ -167,6 +168,27 @@ describe(signalSlice.name, () => {
 			});
 		});
 
+		it('should accept an external subject with arguments as an action', () => {
+			TestBed.runInInjectionContext(() => {
+				const testAge = 50;
+
+				const triggerWithAmount$ = new Subject<number>();
+				const state = signalSlice({
+					initialState,
+					sources: [
+						triggerWithAmount$.pipe(map((amount) => ({ age: amount }))),
+					],
+					actionSources: {
+						triggerWithAmount: triggerWithAmount$,
+					},
+				});
+
+				state.triggerWithAmount(testAge);
+
+				expect(state().age).toEqual(testAge);
+			});
+		});
+
 		it('should create action that updates signal asynchronously', () => {
 			TestBed.runInInjectionContext(() => {
 				const testAge = 35;

diff --git a/libs/ngxtension/signal-slice/src/signal-slice.ts b/libs/ngxtension/signal-slice/src/signal-slice.ts
@@ -40,21 +40,26 @@ type Effects<TEffects extends NamedEffects> = {
 	[K in keyof TEffects]: EffectRef;
 };
 
-type Action<TSignalValue, TValue> = TValue extends void
+type Action<TSignalValue, TValue> = TValue extends [void]
 	? () => Promise<TSignalValue>
-	: unknown extends TValue
+	: [unknown] extends TValue
 	? () => Promise<TSignalValue>
-	: (value: TValue | Observable<TValue>) => Promise<TSignalValue>;
+	: (
+			value: TValue extends [infer TInferred]
+				? TInferred | Observable<TInferred>
+				: TValue | Observable<TValue>
+	  ) => Promise<TSignalValue>;
 
 type ActionMethod<
 	TSignalValue,
 	TActionSource extends NamedActionSources<TSignalValue>[string]
-> = TActionSource extends
-	| ((state: Signal<TSignalValue>, value: infer TValue) => any)
-	| Subject<infer TValue>
-	? TValue extends Observable<infer TObservableValue>
-		? Action<TSignalValue, TObservableValue>
-		: Action<TSignalValue, TValue>
+> = TActionSource extends (
+	state: Signal<TSignalValue>,
+	value: Observable<infer TObservableValue>
+) => any
+	? Action<TSignalValue, [TObservableValue]>
+	: TActionSource extends Subject<infer TSubjectValue>
+	? Action<TSignalValue, [TSubjectValue]>
 	: never;
 
 type ActionMethods<