fix: ensure is_pure takes into account runes (#14333)

* fix: ensure is_pure takes into account runes

* feedback

Author: trueadm

.changeset/slimy-islands-cry.md

@@ -0,0 +1,5 @@
+---
+'svelte': patch
+---
+
+fix: ensure is_pure takes into account $effect.tracking()

packages/svelte/src/compiler/phases/2-analyze/visitors/shared/utils.js

@@ -4,8 +4,10 @@
 /** @import { Scope } from '../../../scope' */
 /** @import { NodeLike } from '../../../../errors.js' */
 import * as e from '../../../../errors.js';
-import { extract_identifiers, object } from '../../../../utils/ast.js';
+import { extract_identifiers } from '../../../../utils/ast.js';
 import * as w from '../../../../warnings.js';
+import * as b from '../../../../utils/builders.js';
+import { get_rune } from '../../../scope.js';
 
 /**
  * @param {AssignmentExpression | UpdateExpression} node
@@ -184,6 +186,7 @@ export function is_pure(node, context) {
 	if (node.type === 'Literal') {
 		return true;
 	}
+
 	if (node.type === 'CallExpression') {
 		if (!is_pure(node.callee, context)) {
 			return false;
@@ -195,10 +198,15 @@ export function is_pure(node, context) {
 		}
 		return true;
 	}
+
 	if (node.type !== 'Identifier' && node.type !== 'MemberExpression') {
 		return false;
 	}
 
+	if (get_rune(b.call(node), context.state.scope) === '$effect.tracking') {
+		return false;
+	}
+
 	/** @type {Expression | Super | null} */
 	let left = node;
 	while (left.type === 'MemberExpression') {

packages/svelte/tests/runtime-legacy/samples/inline-expressions-2/_config.js

@@ -0,0 +1,21 @@
+import { test } from '../../test';
+
+export default test({
+	html: `
+		<p>Without text expression: 7.36</p>
+		<p>With text expression: 7.36</p>
+		<p>With text expression and function call: 7.36</p>
+		<p>With text expression and property access: 4</p>
+		<h1>Hello name!</h1>
+		<p>4</p>
+		<h1>Tracking: true</h1>`,
+
+	ssrHtml: `
+		<p>Without text expression: 7.36</p>
+		<p>With text expression: 7.36</p>
+		<p>With text expression and function call: 7.36</p>
+		<p>With text expression and property access: 4</p>
+		<h1>Hello name!</h1>
+		<p>4</p>
+		<h1>Tracking: false</h1>`
+});

packages/svelte/tests/runtime-runes/samples/inline-expressions/_config.js

@@ -4,3 +4,4 @@
 <p>With text expression and property access: {"test".length}</p>
 <h1>Hello {('name').toUpperCase().toLowerCase()}!</h1>
 <p>{"test".length}</p>
+<h1>Tracking: {$effect.tracking()}</h1>