From 7f043db8b93a09f98c3307535df4b260f7b94c33 Mon Sep 17 00:00:00 2001
From: SerKo <serko.dev@gmail.com>
Date: Sat, 6 Dec 2025 02:21:09 +0800
Subject: [PATCH 1/2] feat: support tsdk path for Eclipse Theia

---
 extensions/vscode/index.ts | 27 ++++++++++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)

diff --git a/extensions/vscode/index.ts b/extensions/vscode/index.ts
index 5532b7512e..ca8e5e65f0 100644
--- a/extensions/vscode/index.ts
+++ b/extensions/vscode/index.ts
@@ -105,9 +105,15 @@ export = defineExtension(() => {
 			});
 		}
 
+		const tsdk = resolveTsdkPath();
+		if (tsdk === undefined) {
+			vscode.window.showErrorMessage('Cannot find TypeScript SDK.');
+			return;
+		}
+
 		client = launch(
 			serverPath ?? vscode.Uri.joinPath(context.extensionUri, 'dist', 'language-server.js').fsPath,
-			vscode.env.appRoot.replace(/\\/g, '/') + '/extensions/node_modules/typescript/lib',
+			tsdk,
 		);
 
 		volarLabs.addLanguageClient(client);
@@ -196,6 +202,25 @@ function launch(serverPath: string, tsdk: string) {
 	return client;
 }
 
+function resolveTsdkPath() {
+	const vscodeTsdk = vscode.env.appRoot.replace(/\\/g, '/') + '/extensions/node_modules/typescript/lib';
+	if (fs.existsSync(vscodeTsdk)) {
+		return vscodeTsdk;
+	}
+
+	const tsExt = vscode.extensions.getExtension('vscode.typescript-language-features');
+	if (tsExt) {
+		// Eclipse Theia
+		// see: https://github.com/eclipse-theia/vscode-builtin-extensions/blob/65c70ec636bd879ef9529d0a2da36f4b99139c40/src/package-vsix.js#L71
+		const theiaTsdk = path.join(tsExt.extensionPath, 'deps', 'typescript', 'lib');
+		if (fs.existsSync(theiaTsdk)) {
+			return theiaTsdk;
+		}
+	}
+
+	return undefined;
+}
+
 function resolveServerPath() {
 	const tsPluginPackPath = path.join(__dirname, '..', 'node_modules', 'vue-typescript-plugin-pack', 'index.js');
 

From dc6675213ebf9799c14d0cc67a412c72c37dfaee Mon Sep 17 00:00:00 2001
From: Johnson Chu <johnsoncodehk@gmail.com>
Date: Sat, 6 Dec 2025 02:39:11 +0800
Subject: [PATCH 2/2] Update index.ts

---
 extensions/vscode/index.ts | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/extensions/vscode/index.ts b/extensions/vscode/index.ts
index ca8e5e65f0..8e82270904 100644
--- a/extensions/vscode/index.ts
+++ b/extensions/vscode/index.ts
@@ -113,7 +113,7 @@ export = defineExtension(() => {
 
 		client = launch(
 			serverPath ?? vscode.Uri.joinPath(context.extensionUri, 'dist', 'language-server.js').fsPath,
-			tsdk,
+			tsdk.replace(/\\/g, '/'),
 		);
 
 		volarLabs.addLanguageClient(client);
@@ -203,7 +203,7 @@ function launch(serverPath: string, tsdk: string) {
 }
 
 function resolveTsdkPath() {
-	const vscodeTsdk = vscode.env.appRoot.replace(/\\/g, '/') + '/extensions/node_modules/typescript/lib';
+	const vscodeTsdk = path.join(vscode.env.appRoot, 'extensions', 'node_modules', 'typescript', 'lib');
 	if (fs.existsSync(vscodeTsdk)) {
 		return vscodeTsdk;
 	}
@@ -217,8 +217,6 @@ function resolveTsdkPath() {
 			return theiaTsdk;
 		}
 	}
-
-	return undefined;
 }
 
 function resolveServerPath() {