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 nodejs/node-v0.x-archive#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: #6709
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>

Author: Trott

test/common.js

@@ -160,7 +160,7 @@ Object.defineProperty(exports, 'opensslCli', {get: function() {
 opensslCli=false;
 }
 returnopensslCli;
-},enumerable: true});
+},enumerable: true});
 
 Object.defineProperty(exports,'hasCrypto',{
 get: function(){
@@ -395,55 +395,6 @@ exports.mustCall = function(fn, expected) {
 };
 };
 
-varetcServicesFileName=path.join('/etc','services');
-if(exports.isWindows){
-etcServicesFileName=path.join(process.env.SystemRoot,'System32','drivers',
-'etc','services');
-}
-
-/*
- * Returns a string that represents the service name associated
- * to the service bound to port "port" and using protocol "protocol".
- *
- * If the service is not defined in the services file, it returns
- * the port number as a string.
- *
- * Returns undefined if /etc/services (or its equivalent on non-UNIX
- * platforms) can't be read.
- */
-exports.getServiceName=functiongetServiceName(port,protocol){
-if(port==null){
-thrownewError('Missing port number');
-}
-
-if(typeofprotocol!=='string'){
-thrownewError('Protocol must be a string');
-}
-
-/*
- * By default, if a service can't be found in /etc/services,
- * its name is considered to be its port number.
- */
-varserviceName=port.toString();
-
-try{
-varservicesContent=fs.readFileSync(etcServicesFileName,
-{encoding: 'utf8'});
-varregexp=`^(\\w+)\\s+\\s${port}/${protocol}\\s`;
-varre=newRegExp(regexp,'m');
-
-varmatches=re.exec(servicesContent);
-if(matches&&matches.length>1){
-serviceName=matches[1];
-}
-}catch(e){
-console.error('Cannot read file: ',etcServicesFileName);
-returnundefined;
-}
-
-returnserviceName;
-};
-
 exports.hasMultiLocalhost=functionhasMultiLocalhost(){
 varTCP=process.binding('tcp_wrap').TCP;
 vart=newTCP();

test/internet/test-dns-ipv4.js

@@ -1,5 +1,5 @@
 'use strict';
-constcommon=require('../common');
+require('../common');
 constassert=require('assert');
 constdns=require('dns');
 constnet=require('net');
@@ -173,24 +173,7 @@ TEST(function test_lookupservice_ip_ipv4(done) {
 if(err)throwerr;
 assert.equal(typeofhost,'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.
- */
-varhttpServiceName=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();
 });
 

test/internet/test-dns-ipv6.js

@@ -182,24 +182,7 @@ TEST(function test_lookupservice_ip_ipv6(done) {
 if(err)throwerr;
 assert.equal(typeofhost,'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.
- */
-varhttpServiceName=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();
 });