diff --git a/test/async-hooks/init-hooks.js b/test/async-hooks/init-hooks.js
index c99383204ffe03..a5f835cdff3aaa 100644
--- a/test/async-hooks/init-hooks.js
+++ b/test/async-hooks/init-hooks.js
@@ -67,7 +67,7 @@ class ActivityCollector {
     const violations = [];
     function v(msg) { violations.push(msg); }
     for (const a of this._activities.values()) {
-      if (types != null && types.indexOf(a.type) < 0) continue;
+      if (types != null && !types.includes(a.type)) continue;
 
       if (a.init && a.init.length > 1) {
         v('Activity inited twice\n' + activityString(a) +
@@ -131,7 +131,7 @@ class ActivityCollector {
 
   activitiesOfTypes(types) {
     if (!Array.isArray(types)) types = [ types ];
-    return this.activities.filter((x) => types.indexOf(x.type) >= 0);
+    return this.activities.filter((x) => types.includes(x.type));
   }
 
   get activities() {
diff --git a/test/parallel/test-repl-tab-complete.js b/test/parallel/test-repl-tab-complete.js
index 994421ffc58a6a..85bcaf9e618ebc 100644
--- a/test/parallel/test-repl-tab-complete.js
+++ b/test/parallel/test-repl-tab-complete.js
@@ -411,7 +411,7 @@ const warningRegEx = new RegExp(
     });
 
     // no `biu`
-    assert.strictEqual(data.indexOf('ele.biu'), -1);
+    assert.strictEqual(data.includes('ele.biu'), false);
   }));
 });