diff --git a/lib/handlebars/compiler/compiler.js b/lib/handlebars/compiler/compiler.js
index 34ef5dd1..8374f031 100644
--- a/lib/handlebars/compiler/compiler.js
+++ b/lib/handlebars/compiler/compiler.js
@@ -66,10 +66,7 @@ Compiler.prototype = {
     };
     if (knownHelpers) {
       for (let name in knownHelpers) {
-        /* istanbul ignore else */
-        if (name in knownHelpers) {
           this.options.knownHelpers[name] = knownHelpers[name];
-        }
       }
     }