diff --git a/test/parallel/test-whatwg-encoding-textdecoder-fatal.js b/test/parallel/test-whatwg-encoding-textdecoder-fatal.js
index be37f5097c504e..aa945b61b10e72 100644
--- a/test/parallel/test-whatwg-encoding-textdecoder-fatal.js
+++ b/test/parallel/test-whatwg-encoding-textdecoder-fatal.js
@@ -88,3 +88,15 @@ bad.forEach((t) => {
   assert(!new TextDecoder().fatal);
   assert(new TextDecoder('utf-8', { fatal: true }).fatal);
 }
+
+{
+  const notArrayBufferViewExamples = [false, {}, 1, '', new Error()];
+  notArrayBufferViewExamples.forEach((invalidInputType) => {
+    common.expectsError(() => {
+      new TextDecoder(undefined, null).decode(invalidInputType);
+    }, {
+      code: 'ERR_INVALID_ARG_TYPE',
+      type: TypeError
+    });
+  });
+}
diff --git a/test/parallel/test-whatwg-encoding-textdecoder.js b/test/parallel/test-whatwg-encoding-textdecoder.js
index 37fbe12757134e..6d1db2ec33faad 100644
--- a/test/parallel/test-whatwg-encoding-textdecoder.js
+++ b/test/parallel/test-whatwg-encoding-textdecoder.js
@@ -75,6 +75,14 @@ if (common.hasIntl) {
     });
 }
 
+// Test TextDecoder, label undefined, options null
+{
+  const dec = new TextDecoder(undefined, null);
+  assert.strictEqual(dec.encoding, 'utf-8');
+  assert.strictEqual(dec.fatal, false);
+  assert.strictEqual(dec.ignoreBOM, false);
+}
+
 // Test TextDecoder, UTF-16le
 {
   const dec = new TextDecoder('utf-16le');