fix: treat a script tag as top-level if it's the first tag in file (#2886)

Author: jasonlyu123

.changeset/plenty-moments-grab.md

@@ -0,0 +1,5 @@
+---
+'svelte-language-server': patch
+---
+
+fix: always treat a script tag as top-level if it's the first tag in the file

packages/language-server/src/lib/documents/utils.ts

@@ -72,6 +72,15 @@ function extractTags(
      * If that is BEFORE `{#X`, we are inside a moustache tag.
      */
     function isNotInsideControlFlowTag(tag: Node) {
+        const tagIndex = rootNodes.indexOf(tag);
+        // Quick check: if the tag has nothing before it, it can't be inside a control flow tag
+        // This also works around a case where the tag is treated as under a control flow tag when vscode-html-languageservice parses something wrong
+        if (tagIndex === 0) {
+            const startContent = text.substring(0, tag.start);
+            if (startContent.trim() === '') {
+                return true;
+            }
+        }
         const nodes = rootNodes.slice(rootNodes.indexOf(tag));
         const rootContentAfterTag = nodes
             .map((node, idx) => {

packages/language-server/test/lib/documents/utils.test.ts

@@ -50,7 +50,7 @@ describe('document/utils', () => {
             assert.deepStrictEqual(extractStyleTag(text), null);
         });
 
-        it('is canse sensitive to style/script', () => {
+        it('is case sensitive to style/script', () => {
             const text = `
             <Style></Style>
             <Script></Script>
@@ -344,6 +344,20 @@ describe('document/utils', () => {
                 container: { start: 151, end: 181 }
             });
         });
+
+        it('extract tag correctly if nothing is before the tag', () => {
+            const text = `<script>let value = 2</script>
+                {/if}`;
+            assert.deepStrictEqual(extractScriptTags(text)?.script, {
+                content: 'let value = 2',
+                attributes: {},
+                start: 8,
+                end: 21,
+                startPos: Position.create(0, 8),
+                endPos: Position.create(0, 21),
+                container: { start: 0, end: 30 }
+            });
+        });
     });
 
     describe('#getLineAtPosition', () => {