sveltejs · baseballyama · Apr 3, 2025 · Apr 3, 2025 · Apr 3, 2025
diff --git a/.changeset/gold-planes-retire.md b/.changeset/gold-planes-retire.md
@@ -0,0 +1,5 @@
+---
+"svelte-eslint-parser": patch
+---
+
+fix: crash with `$derived()` in template using ts
diff --git a/src/parser/typescript/analyze/index.ts b/src/parser/typescript/analyze/index.ts
@@ -73,15 +73,26 @@ export function analyzeTypeScriptInSvelte(
 
   analyzeRuneVariables(result, ctx, context.svelteParseContext);
 
-  applyTransforms(
-    [
-      ...analyzeReactiveScopes(result),
-      ...analyzeDollarDerivedScopes(result, context.svelteParseContext),
-    ],
-    ctx,
-  );
+  const scriptTransformers: TransformInfo[] = [
+    ...analyzeReactiveScopes(result),
+  ];
+  const templateTransformers: TransformInfo[] = [];
+  for (const transform of analyzeDollarDerivedScopes(
+    result,
+    context.svelteParseContext,
+  )) {
+    if (transform.node.range[0] < code.script.length) {
+      scriptTransformers.push(transform);
+    } else {
+      templateTransformers.push(transform);
+    }
+  }
 
-  analyzeRenderScopes(code, ctx);
+  applyTransforms(scriptTransformers, ctx);
+
+  analyzeRenderScopes(code, ctx, () =>
+    applyTransforms(templateTransformers, ctx),
+  );
 
   // When performing type checking on TypeScript code that is not a module, the error `Cannot redeclare block-scoped variable 'xxx'`. occurs. To fix this, add an `export`.
   // see: https://github.com/sveltejs/svelte-eslint-parser/issues/557
@@ -625,10 +636,12 @@ function* analyzeDollarDerivedScopes(
 function analyzeRenderScopes(
   code: { script: string; render: string; rootScope: string },
   ctx: VirtualTypeScriptContext,
+  analyzeInTemplate: () => void,
 ) {
   ctx.appendOriginal(code.script.length);
   const renderFunctionName = ctx.generateUniqueId("render");
   ctx.appendVirtualScript(`export function ${renderFunctionName}(){`);
+  analyzeInTemplate();
   ctx.appendOriginal(code.script.length + code.render.length);
   ctx.appendVirtualScript(`}`);
   ctx.restoreContext.addRestoreStatementProcess((node, result) => {

diff --git a/tests/fixtures/parser/ast/svelte5/$derived-in-template-with-ts01-input.svelte b/tests/fixtures/parser/ast/svelte5/$derived-in-template-with-ts01-input.svelte
@@ -0,0 +1,5 @@
+<script lang="ts">
+    import MyComponent from './MyComponent.svelte';
+</script>
+
+<MyComponent :foo={() => $derived(0)} />
diff --git a/src/parser/template.ts b/src/parser/template.ts
 import type {} from "svelte"; // FIXME: Workaround to get type information for "svelte/compiler"
 import { parse } from "svelte/compiler";
 import type * as Compiler from "./svelte-ast-types-for-v5.js";
 import type * as SvAST from "./svelte-ast-types.js";
diff --git a/src/parser/converts/const.ts b/src/parser/converts/const.ts
  };

  // Link declaration and declarations for backward compatibility.
  // TODO Remove in v2 and later.
  Object.defineProperty(mustache, "declaration", {
    get() {
      return mustache.declarations[0];
diff --git a/src/parser/converts/attr.ts b/src/parser/converts/attr.ts
    (key as any).parent = sAttr;
    ctx.scriptLet.addObjectShorthandProperty(attribute.key, sAttr, (es) => {
      if (
        // FIXME: Older parsers may use the same node. In that case, do not replace.
        // We will drop support for ESLint v7 in the next major version and remove this branch.
        es.key !== es.value
      ) {
diff --git a/src/ast/html.ts b/src/ast/html.ts
  /**
   * @deprecated Use `declarations` instead.
   */
  declaration: ESTree.VariableDeclarator; // TODO Remove in v2 and later.
  declarations: [ESTree.VariableDeclarator];
  parent:
    | SvelteProgram
	import type {} from "svelte"; // FIXME: Workaround to get type information for "svelte/compiler"
Check warning on line 1 in src/parser/template.ts GitHub Actions / lint `Unexpected 'fixme' comment: 'FIXME: Workaround to get type...'`
	import { parse } from "svelte/compiler";
	import type * as Compiler from "./svelte-ast-types-for-v5.js";
	import type * as SvAST from "./svelte-ast-types.js";
	};

	// Link declaration and declarations for backward compatibility.
	// TODO Remove in v2 and later.
Check warning on line 22 in src/parser/converts/const.ts GitHub Actions / lint `Unexpected 'todo' comment: 'TODO Remove in v2 and later.'`
	Object.defineProperty(mustache, "declaration", {
	get() {
	return mustache.declarations[0];
	(key as any).parent = sAttr;
	ctx.scriptLet.addObjectShorthandProperty(attribute.key, sAttr, (es) => {
	if (
	// FIXME: Older parsers may use the same node. In that case, do not replace.
Check warning on line 174 in src/parser/converts/attr.ts GitHub Actions / lint `Unexpected 'fixme' comment: 'FIXME: Older parsers may use the same...'`
	// We will drop support for ESLint v7 in the next major version and remove this branch.
	es.key !== es.value
	) {
	/**
	* @deprecated Use `declarations` instead.
	*/
	declaration: ESTree.VariableDeclarator; // TODO Remove in v2 and later.
Check warning on line 269 in src/ast/html.ts GitHub Actions / lint `Unexpected 'todo' comment: 'TODO Remove in v2 and later.'`
	declarations: [ESTree.VariableDeclarator];
	parent:
	\| SvelteProgram