From d361020f6dff25aa0e2a48b06b07b83555676c92 Mon Sep 17 00:00:00 2001
From: Keita Akutsu <kakts.git@gmail.com>
Date: Sat, 7 Jul 2018 02:27:33 +0900
Subject: [PATCH 1/2] test: add test for dns.promises.resolve .

---
 test/parallel/test-dns-promises-resolve.js | 43 ++++++++++++++++++++++
 1 file changed, 43 insertions(+)
 create mode 100644 test/parallel/test-dns-promises-resolve.js

diff --git a/test/parallel/test-dns-promises-resolve.js b/test/parallel/test-dns-promises-resolve.js
new file mode 100644
index 00000000000000..fb51baeab6a862
--- /dev/null
+++ b/test/parallel/test-dns-promises-resolve.js
@@ -0,0 +1,43 @@
+'use strict';
+const common = require('../common');
+const assert = require('assert');
+
+const dnsPromises = require('dns').promises;
+
+common.crashOnUnhandledRejection();
+
+// Error when rrtype is invalid.
+{
+  const rrtype = 'DUMMY';
+  common.expectsError(
+    () => dnsPromises.resolve('example.org', rrtype),
+    {
+      code: 'ERR_INVALID_OPT_VALUE',
+      type: TypeError,
+      message: `The value "${rrtype}" is invalid for option "rrtype"`
+    }
+  );
+}
+
+// Error when rrtype is a number.
+{
+  const rrtype = 0;
+  common.expectsError(
+    () => dnsPromises.resolve('example.org', rrtype),
+    {
+      code: 'ERR_INVALID_ARG_TYPE',
+      type: TypeError,
+      message: `The "rrtype" argument must be of type string. Received type ${typeof rrtype}`
+    }
+  );
+}
+
+// rrtype is undefined, it's same as resolve4
+{
+  (async function() {
+    const rrtype = undefined;
+    const result = await dnsPromises.resolve('example.org');
+    assert.ok(result !== undefined);
+    assert.ok(result.length > 0);
+  })();
+}

From b94eda2838e597bafde24d5c7b47bdc86c37e784 Mon Sep 17 00:00:00 2001
From: Keita Akutsu <kakts.git@gmail.com>
Date: Sat, 7 Jul 2018 03:02:40 +0900
Subject: [PATCH 2/2] test: refactor test-dns-promises-resolve.js

---
 test/parallel/test-dns-promises-resolve.js | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/test/parallel/test-dns-promises-resolve.js b/test/parallel/test-dns-promises-resolve.js
index fb51baeab6a862..fcaa8977a5ba18 100644
--- a/test/parallel/test-dns-promises-resolve.js
+++ b/test/parallel/test-dns-promises-resolve.js
@@ -27,7 +27,8 @@ common.crashOnUnhandledRejection();
     {
       code: 'ERR_INVALID_ARG_TYPE',
       type: TypeError,
-      message: `The "rrtype" argument must be of type string. Received type ${typeof rrtype}`
+      message: 'The "rrtype" argument must be of type string. ' +
+               `Received type ${typeof rrtype}`
     }
   );
 }
@@ -36,7 +37,7 @@ common.crashOnUnhandledRejection();
 {
   (async function() {
     const rrtype = undefined;
-    const result = await dnsPromises.resolve('example.org');
+    const result = await dnsPromises.resolve('example.org', rrtype);
     assert.ok(result !== undefined);
     assert.ok(result.length > 0);
   })();