diff --git a/packages/color-diff-napi/src/index.ts b/packages/color-diff-napi/src/index.ts
index f8c0d70b2..afaf924ea 100644
--- a/packages/color-diff-napi/src/index.ts
+++ b/packages/color-diff-napi/src/index.ts
@@ -528,7 +528,7 @@ function highlightLine(
     // hljs throws on unknown language despite ignoreIllegals
     return [[defaultStyle(theme), code]]
   }
-  const emitter = result._emitter;
+  const emitter = result._emitter || {};
   if (!hasRootNode(emitter)) {
     if (!loggedEmitterShapeError) {
       loggedEmitterShapeError = true