internet/test-dns fails on v6.x

[gibfahn]

• Version: 6.13.0
• Platform: macOS High Sierra (suspected to be all platforms though)
• Subsystem: test

Reproduction:

# Inside a clone of node:
git checkout v6.13.0
nvm install 6.13.0
node test/internet/test-dns.js

Error:

▶▶▶ node test/internet/test-dns.js                                                                                                                                      ~/wrk/com/node (!tags/v6.13.0^0✦)
test_reverse_bogus
test_resolve4_ttl
looking up nodejs.org...
test_resolve6_ttl
nodejs.org =  [ '104.20.22.46', '104.20.23.46' ]
test_resolveMx
test_resolveMx_failure
test_resolveNs
test_resolveNs_failure
test_resolveSrv
test_resolveSrv_failure
test_resolvePtr
test_resolvePtr_failure
test_resolveNaptr
test_resolveNaptr_failure
test_resolveSoa
test_resolveSoa_failure
test_resolveCname
test_resolveCname_failure
test_resolveTxt
test_resolveTxt_failure
17 tests completed

assert.js:84
  throw new assert.AssertionError({
  ^
AssertionError: 2 === 1
    at /Users/gib/wrk/com/node/test/internet/test-dns.js:361:12
    at QueryReqWrap.asyncCallback [as callback] (dns.js:62:16)
    at QueryReqWrap.onresolve [as oncomplete] (dns.js:221:10)

[gibfahn]

This doesn't fail on 8.x, so I suspect a change was made to the tests that hasn't been backported yet.

[gibfahn]

Problem is in this function:

node/test/internet/test-dns.js

Lines 369 to 372 in 4eb45b8

	TEST(function test_resolveTxt(done) {
	const req = dns.resolveTxt(addresses.TXT_HOST, function(err, records) {
	assert.ifError(err);
	assert.strictEqual(records.length, 1);

On v6.x we expect 'google.com' to have records.length == 1, but it is now two:

▶▶▶ node -p "require('dns').resolveTxt('google.com', (err, records) => { console.log(records.length) } )"                                                               ~/wrk/com/node (!tags/v6.13.0^0✦)
QueryReqWrap {
  bindingName: 'queryTxt',
  callback: { [Function: asyncCallback] immediately: true },
  hostname: 'google.com',
  oncomplete: [Function: onresolve],
  ttl: false }
2

On master we check TXT_HOST instead, which is set to:

node/test/common/internet.js

Line 38 in 4eb45b8

TXT_HOST: 'nodejs.org',

[gibfahn]

Basically we need to backport #16390 to v6.x.

@joyeecheung is that something you'd be willing to do?

[joyeecheung]

@gibfahn I can do that, just have not found the time recently. I'll try to backport #16390 and #18547 (actual fix to the the TXT record test) this week

[apapirovski]

@joyeecheung would you still like to follow up on this?

[joyeecheung]

@apapirovski Probably not going to need it now that 6.x is near end of life.