feat: add $state.eager

Author: baseballyama

.changeset/green-keys-clap.md

@@ -0,0 +1,5 @@
+---
+"svelte-eslint-parser": minor
+---
+
+feat: add `$state.eager`

package.json

@@ -107,8 +107,8 @@
     "prettier-plugin-svelte": "^3.4.0",
     "rimraf": "^6.0.1",
     "semver": "^7.7.2",
-    "svelte": "^5.38.8",
-    "svelte2tsx": "^0.7.42",
+    "svelte": "^5.41.0",
+    "svelte2tsx": "^0.7.45",
     "tsx": "^4.20.5",
     "typescript": "~5.9.2",
     "typescript-eslint": "^8.43.0",

src/parser/typescript/analyze/index.ts

@@ -399,12 +399,15 @@ function analyzeRuneVariables(
       continue;
     }
     switch (globalName) {
-      // See https://github.com/sveltejs/svelte/blob/3fa3dd78a1cbaa88a1571977b76bf6f02ed4231d/packages/svelte/types/index.d.ts#L3093
+      // See https://github.com/sveltejs/svelte/blob/bd2d3db6d0d7a931c2e84c38a5c537e30dda1dbe/packages/svelte/types/index.d.ts#L3124
       case "$state": {
         appendDeclareFunctionVirtualScripts(globalName, [
           "<T>(initial: T): T",
           "<T>(): T | undefined",
         ]);
+        appendDeclareNamespaceVirtualScripts(globalName, [
+          "export function eager<T>(value: T): T",
+        ]);
         appendDeclareNamespaceVirtualScripts(globalName, [
           "export function raw<T>(initial: T): T;",
           "export function raw<T>(): T | undefined;",

tests/fixtures/parser/ast/svelte5/$state-eager-config.json

@@ -0,0 +1,5 @@
+{
+	"svelteFeatures": {
+		"runes": true
+	}
+}

tests/fixtures/parser/ast/svelte5/$state-eager-input.svelte

@@ -0,0 +1,18 @@
+<script>
+	let a = $state(1);
+	let b = $state(2);
+
+	async function add(a, b) {
+		await new Promise((f) => setTimeout(f, 500)); // artificial delay
+		return a + b;
+	}
+</script>
+
+<button onclick={() => a++}>a++</button>
+<button onclick={() => b++}>b++</button>
+
+<p>{$state.eager(a)} + {$state.eager(b)} = {await add(a, b)}</p>
+
+{#if $effect.pending()}
+	<p>pending promises: {$effect.pending()}</p>
+{/if}