diff --git a/packages/plugin-ext/src/plugin/languages/selection-range.ts b/packages/plugin-ext/src/plugin/languages/selection-range.ts
index 6d469570bd9e1..6f668b5c8d5df 100644
--- a/packages/plugin-ext/src/plugin/languages/selection-range.ts
+++ b/packages/plugin-ext/src/plugin/languages/selection-range.ts
@@ -63,7 +63,7 @@ export class SelectionRangeProviderAdapter {
 
                 while (true) {
                     if (!selectionRange.range.contains(last)) {
-                        return Promise.reject('INVALID selection range, must contain the previous range');
+                        return Promise.reject(new Error('INVALID selection range, must contain the previous range'));
                     }
                     oneResult.push(Converter.fromSelectionRange(selectionRange));
                     if (!selectionRange.parent) {