add test

Author: eladkishon

lib/internal/repl/utils.js

@@ -394,7 +394,7 @@ function setupPreview(repl, contextSymbol, bufferSymbol, active) {
     }
 
     const inputPreviewCallback = (error, inspected) => {
-      if (inspected === null) {
+      if (inspected == null) {
         return;
       }
 

test/parallel/test-repl-history-navigation.js

@@ -68,6 +68,8 @@ const prev = process.features.inspector;
 
 let completions = 0;
 
+process.on('warning', common.mustNotCall());
+
 const tests = [
   { // Creates few history to navigate for
     env: { NODE_REPL_HISTORY: defaultHistoryPath },
@@ -554,6 +556,13 @@ const tests = [
     expected: [],
     clean: false
   },
+  {
+    env: { NODE_REPL_HISTORY: defaultHistoryPath },
+    test: [ 'const util = {}', ENTER,
+            'ut', RIGHT, ENTER],
+    expected: [],
+    clean: false
+  },
 ];
 const numtests = tests.length;