diff --git a/packages/tailwindcss-language-service/src/util/getLanguageBoundaries.ts b/packages/tailwindcss-language-service/src/util/getLanguageBoundaries.ts
index bbe36ba68d407ebe4460cbf9095b9d689d148d17..d4bb4a0f93c7707248e5cf423040c03e0669dfa4 100644
--- a/packages/tailwindcss-language-service/src/util/getLanguageBoundaries.ts
+++ b/packages/tailwindcss-language-service/src/util/getLanguageBoundaries.ts
@@ -96,10 +96,8 @@   doc: TextDocument,
   text: string = doc.getText()
 ): LanguageBoundary[] | null {
   let cacheKey = `${doc.languageId}:${text}`
-
-  let cachedBoundaries = cache.get(cacheKey)
-  if (cachedBoundaries !== undefined) {
-    return cachedBoundaries
+  if (cache.has(cacheKey)) {
+    return cache.get(cacheKey)
   }
 
   let defaultType = isVueDoc(doc)