test: remove common.getServiceName()

Replace lightly-used services file parsing in favor of
confirming one of a small number of allowable values in service name
lookup tests.

In https://github.com/nodejs/node-v0.x-archive/issues/8047, it was
decided that this sort of service file parsing was superior to
hardcoding acceptable values, but I'm not convinced:

* No guarantee that the host uses /etc/services before, e.g., nscd.
* Increases complexity of tests without guaranteeing robustness.

I think that simply checking against a small set of expected values
may be a better solution. Ideally, there would also be a unit test that
used a test double for the appropriate `cares` function and confirms
that it is called with the correct parameters, but now we're getting way
ahead of ourselves.

PR-URL: https://github.com/nodejs/node/pull/6709
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>

2 files changed, 3 insertions, 37 deletions

diff --git a/test/internet/test-dns-ipv4.js b/test/internet/test-dns-ipv4.js
index 0781496392..06c1056a26 100644
--- a/test/internet/test-dns-ipv4.js
+++ b/test/internet/test-dns-ipv4.js
@@ -1,5 +1,5 @@
 'use strict';
-const common = require('../common');
+require('../common');
 const assert = require('assert');
 const dns = require('dns');
 const net = require('net');
@@ -173,24 +173,7 @@ TEST(function test_lookupservice_ip_ipv4(done) {
     if (err) throw err;
     assert.equal(typeof host, 'string');
     assert(host);
-
-    /*
-     * Retrieve the actual HTTP service name as setup on the host currently
-     * running the test by reading it from /etc/services. This is not ideal,
-     * as the service name lookup could use another mechanism (e.g nscd), but
-     * it's already better than hardcoding it.
-     */
-    var httpServiceName = common.getServiceName(80, 'tcp');
-    if (!httpServiceName) {
-      /*
-       * Couldn't find service name, reverting to the most sensible default
-       * for port 80.
-       */
-      httpServiceName = 'http';
-    }
-
-    assert.strictEqual(service, httpServiceName);
-
+    assert(['http', 'www', '80'].includes(service));
     done();
   });
 
diff --git a/test/internet/test-dns-ipv6.js b/test/internet/test-dns-ipv6.js
index 2929361f16..a9e46c8478 100644
--- a/test/internet/test-dns-ipv6.js
+++ b/test/internet/test-dns-ipv6.js
@@ -182,24 +182,7 @@ TEST(function test_lookupservice_ip_ipv6(done) {
     if (err) throw err;
     assert.equal(typeof host, 'string');
     assert(host);
-
-    /*
-     * Retrieve the actual HTTP service name as setup on the host currently
-     * running the test by reading it from /etc/services. This is not ideal,
-     * as the service name lookup could use another mechanism (e.g nscd), but
-     * it's already better than hardcoding it.
-     */
-    var httpServiceName = common.getServiceName(80, 'tcp');
-    if (!httpServiceName) {
-      /*
-       * Couldn't find service name, reverting to the most sensible default
-       * for port 80.
-       */
-      httpServiceName = 'http';
-    }
-
-    assert.strictEqual(service, httpServiceName);
-
+    assert(['http', 'www', '80'].includes(service));
     done();
   });