test: should work with chained patch functions

src/signals/tests/immer-patch-state.jest.ts

@@ -1,18 +1,27 @@
-import { signalStore, withComputed, withState } from '@ngrx/signals';
+import {
+	PartialStateUpdater,
+	signalStore,
+	withComputed,
+	withState,
+} from '@ngrx/signals';
 import { immerPatchState } from 'ngrx-immer/signals';
 import { computed, effect } from '@angular/core';
 import { TestBed } from '@angular/core/testing';
 
-const UserState = signalStore(withState({
-	id: 1,
-	name: { firstname: 'Konrad', lastname: 'Schultz' },
-	address: { city: 'Vienna', zip: '1010' },
-}), withComputed(({ name }) => ({ prettyName: computed(() => `${name.firstname()} ${name.lastname()}`) })));
-
+const UserState = signalStore(
+	withState({
+		id: 1,
+		name: { firstname: 'Konrad', lastname: 'Schultz' },
+		address: { city: 'Vienna', zip: '1010' },
+	}),
+	withComputed(({ name }) => ({
+		prettyName: computed(() => `${name.firstname()} ${name.lastname()}`),
+	})),
+);
 
 describe('immerPatchState', () => {
 	const setup = () => {
-		return new UserState;
+		return new UserState();
 	};
 
 	it('should do a sanity check', () => {
@@ -27,20 +36,56 @@ describe('immerPatchState', () => {
 		immerPatchState(userState, { number: 1 });
 
 		//@ts-expect-error number is not a property
-		immerPatchState(userState, state => ({ number: 1 }));
+		immerPatchState(userState, (state) => ({ number: 1 }));
 	});
 
 	it('should allow patching with object literal', () => {
 		const userState = setup();
-		immerPatchState(userState, { name: { firstname: 'Lucy', lastname: 'Sanders' } });
+		immerPatchState(userState, {
+			name: { firstname: 'Lucy', lastname: 'Sanders' },
+		});
 		expect(userState.prettyName()).toBe('Lucy Sanders');
 	});
 
 	describe('update with return value', () => {
 		it('should work with the default patch function', () => {
 			const userState = setup();
-			immerPatchState(userState, ({ name }) => ({ name: { firstname: name.firstname, lastname: 'Sanders' } }));
+			immerPatchState(userState, ({ name }) => ({
+				name: { firstname: name.firstname, lastname: 'Sanders' },
+			}));
+			expect(userState.prettyName()).toBe('Konrad Sanders');
+		});
+
+		it('should work with chained patch functions', () => {
+			const userState = setup();
+
+			function updateNames<
+				T extends {
+					name: { firstname: string; lastname: string };
+				},
+			>(newState: T): PartialStateUpdater<T> {
+				return (state) => {
+					return {
+						...state,
+						...newState
+					};
+				};
+			}
+
+			immerPatchState(
+				userState,
+				updateNames({ name: { firstname: 'Konrad', lastname: 'Sanders' } }),
+				(state) => {
+					state.id = 2;
+				},
+				(state) => {
+					state.address = { city: 'Updated', zip: '1234' };
+				},
+			);
+
 			expect(userState.prettyName()).toBe('Konrad Sanders');
+			expect(userState.id()).toBe(2);
+			expect(userState.address()).toEqual({ city: 'Updated', zip: '1234' });
 		});
 
 		it('should not emit other signals', () => {
@@ -54,7 +99,9 @@ describe('immerPatchState', () => {
 				TestBed.flushEffects();
 
 				expect(effectCounter).toBe(1);
-				immerPatchState(userState, ({ name }) => ({ name: { firstname: name.firstname, lastname: 'Sanders' } }));
+				immerPatchState(userState, ({ name }) => ({
+					name: { firstname: name.firstname, lastname: 'Sanders' },
+				}));
 
 				TestBed.flushEffects();
 				expect(effectCounter).toBe(1);
@@ -68,16 +115,19 @@ describe('immerPatchState', () => {
 				immerPatchState(userState, (state) => {
 					state.name.lastname = 'Sanders';
 					return state;
-				})).toThrow('[Immer] An immer producer returned a new value *and* modified its draft.');
+				}),
+			).toThrow(
+				'[Immer] An immer producer returned a new value *and* modified its draft.',
+			);
 		});
 	});
 
 	describe('update without returning a value', () => {
 		it('should allow a mutable update', () => {
 			const userState = setup();
-			immerPatchState(userState, (state => {
+			immerPatchState(userState, (state) => {
 				state.name = { firstname: 'Lucy', lastname: 'Sanders' };
-			}));
+			});
 			expect(userState.prettyName()).toBe('Lucy Sanders');
 		});
 
@@ -92,9 +142,9 @@ describe('immerPatchState', () => {
 				TestBed.flushEffects();
 
 				expect(effectCounter).toBe(1);
-				immerPatchState(userState, (state => {
+				immerPatchState(userState, (state) => {
 					state.name = { firstname: 'Lucy', lastname: 'Sanders' };
-				}));
+				});
 
 				TestBed.flushEffects();
 				expect(effectCounter).toBe(1);
@@ -115,25 +165,24 @@ describe('immerPatchState', () => {
 			});
 			effect(() => {
 				userState.address();
-				addressEffectCounter++
+				addressEffectCounter++;
 			});
 			effect(() => {
 				userState.name();
-				nameEffectCounter++
+				nameEffectCounter++;
 			});
 
-
 			// first run
 			TestBed.flushEffects();
 			expect(idEffectCounter).toBe(1);
 			expect(addressEffectCounter).toBe(1);
 			expect(nameEffectCounter).toBe(1);
 
 			// change
-			immerPatchState(userState, (state => {
+			immerPatchState(userState, (state) => {
 				state.name = { firstname: 'Lucy', lastname: 'Sanders' };
-				state.address.zip = '1020'
-			}));
+				state.address.zip = '1020';
+			});
 
 			// second run
 			TestBed.flushEffects();