chore: fix signals test suite

now simulates a component environment more correctly

packages/svelte/tests/signals/test.ts

@@ -1,14 +1,28 @@
 import { describe, assert, it } from 'vitest';
 import * as $ from '../../src/internal/client/runtime';
 
-function run_test(runes: boolean, fn: () => void) {
+/**
+ * @param runes runes mode
+ * @param fn A function that returns a function because we first need to setup all the signals
+ * 			 and then execute the test in order to simulate a real component
+ */
+function run_test(runes: boolean, fn: () => () => void) {
 	return () => {
 		// Create a component context to test runes vs legacy mode
 		$.push({}, runes);
 		// Create a render context so that effect validations etc don't fail
-		const signal = $.render_effect(fn, null, true, true);
-		$.destroy_signal(signal);
+		let execute: any;
+		const signal = $.render_effect(
+			() => {
+				execute = fn();
+			},
+			null,
+			true,
+			true
+		);
 		$.pop();
+		execute();
+		$.destroy_signal(signal);
 	};
 }
 
@@ -23,14 +37,16 @@ describe('signals', () => {
 
 		let count = $.source(0);
 		let double = $.derived(() => $.get(count) * 2);
-
 		$.effect(() => {
 			log.push(`${$.get(count)}:${$.get(double)}`);
 		});
-		$.flushSync(() => $.set(count, 1));
-		$.flushSync(() => $.set(count, 2));
 
-		assert.deepEqual(log, ['0:0', '1:2', '2:4']);
+		return () => {
+			$.flushSync(() => $.set(count, 1));
+			$.flushSync(() => $.set(count, 2));
+
+			assert.deepEqual(log, ['0:0', '1:2', '2:4']);
+		};
 	});
 
 	test('multiple effects with state and derived in it#1', () => {
@@ -46,10 +62,12 @@ describe('signals', () => {
 			log.push(`B:${$.get(double)}`);
 		});
 
-		$.flushSync(() => $.set(count, 1));
-		$.flushSync(() => $.set(count, 2));
+		return () => {
+			$.flushSync(() => $.set(count, 1));
+			$.flushSync(() => $.set(count, 2));
 
-		assert.deepEqual(log, ['A:0:0', 'B:0', 'A:1:2', 'B:2', 'A:2:4', 'B:4']);
+			assert.deepEqual(log, ['A:0:0', 'B:0', 'A:1:2', 'B:2', 'A:2:4', 'B:4']);
+		};
 	});
 
 	test('multiple effects with state and derived in it#2', () => {
@@ -65,10 +83,12 @@ describe('signals', () => {
 			log.push(`B:${$.get(count)}:${$.get(double)}`);
 		});
 
-		$.flushSync(() => $.set(count, 1));
-		$.flushSync(() => $.set(count, 2));
+		return () => {
+			$.flushSync(() => $.set(count, 1));
+			$.flushSync(() => $.set(count, 2));
 
-		assert.deepEqual(log, ['A:0', 'B:0:0', 'A:2', 'B:1:2', 'A:4', 'B:2:4']);
+			assert.deepEqual(log, ['A:0', 'B:0:0', 'A:2', 'B:1:2', 'A:4', 'B:2:4']);
+		};
 	});
 
 	test('derived from state', () => {
@@ -80,10 +100,13 @@ describe('signals', () => {
 		$.effect(() => {
 			log.push($.get(double));
 		});
-		$.flushSync(() => $.set(count, 1));
-		$.flushSync(() => $.set(count, 2));
 
-		assert.deepEqual(log, [0, 2, 4]);
+		return () => {
+			$.flushSync(() => $.set(count, 1));
+			$.flushSync(() => $.set(count, 2));
+
+			assert.deepEqual(log, [0, 2, 4]);
+		};
 	});
 
 	test('derived from derived', () => {
@@ -96,10 +119,13 @@ describe('signals', () => {
 		$.effect(() => {
 			log.push($.get(quadruple));
 		});
-		$.flushSync(() => $.set(count, 1));
-		$.flushSync(() => $.set(count, 2));
 
-		assert.deepEqual(log, [0, 4, 8]);
+		return () => {
+			$.flushSync(() => $.set(count, 1));
+			$.flushSync(() => $.set(count, 2));
+
+			assert.deepEqual(log, [0, 4, 8]);
+		};
 	});
 
 	test('https://perf.js.hyoo.ru/#!bench=9h2as6_u0mfnn', () => {
@@ -116,31 +142,33 @@ describe('signals', () => {
 		const E = $.derived(() => hard($.get(C) + $.get(A) + $.get(D)[0]!, 'E'));
 		const F = $.derived(() => hard($.get(D)[0]! && $.get(B), 'F'));
 		const G = $.derived(() => $.get(C) + ($.get(C) || $.get(E) % 2) + $.get(D)[0]! + $.get(F));
-		let H = $.effect(() => {
+		$.effect(() => {
 			res.push(hard($.get(G), 'H'));
 		});
-		let I = $.effect(() => {
+		$.effect(() => {
 			res.push($.get(G));
 		});
-		let J = $.effect(() => {
+		$.effect(() => {
 			res.push(hard($.get(F), 'J'));
 		});
 
-		$.flushSync();
-
-		let i = 2;
-		while (--i) {
-			res.length = 0;
-			$.set(B, 1);
-			$.set(A, 1 + i * 2);
-			$.flushSync();
-
-			$.set(A, 2 + i * 2);
-			$.set(B, 2);
+		return () => {
 			$.flushSync();
 
-			assert.equal(res.length, 4);
-			assert.deepEqual(res, [3198, 1601, 3195, 1598]);
-		}
+			let i = 2;
+			while (--i) {
+				res.length = 0;
+				$.set(B, 1);
+				$.set(A, 1 + i * 2);
+				$.flushSync();
+
+				$.set(A, 2 + i * 2);
+				$.set(B, 2);
+				$.flushSync();
+
+				assert.equal(res.length, 4);
+				assert.deepEqual(res, [3198, 1601, 3195, 1598]);
+			}
+		};
 	});
 });