test: improve dns lookup coverage

Adding tests covering promises-related code paths. PR-URL: #30777 Reviewed-By: Rich Trott <[email protected]> Reviewed-By: Ben Coe <[email protected]> Reviewed-By: Ruben Bridgewater <[email protected]>

Author: KeeReal

test/parallel/test-dns-lookup-promises.js

@@ -0,0 +1,139 @@
+// Flags: --expose-internals
+'use strict';
+constcommon=require('../common');
+constassert=require('assert');
+const{ internalBinding }=require('internal/test/binding');
+constcares=internalBinding('cares_wrap');
+
+// Stub `getaddrinfo` to proxy its call dynamic stub. This has to be done before
+// we load the `dns` module to guarantee that the `dns` module uses the stub.
+letgetaddrinfoStub=null;
+cares.getaddrinfo=(req)=>getaddrinfoStub(req);
+
+constdnsPromises=require('dns').promises;
+
+functiongetaddrinfoNegative(){
+returnfunctiongetaddrinfoNegativeHandler(req){
+constoriginalReject=req.reject;
+req.resolve=common.mustNotCall();
+req.reject=common.mustCall(originalReject);
+req.oncomplete(internalBinding('uv').UV_ENOMEM);
+};
+}
+
+functiongetaddrinfoPositive(addresses){
+returnfunctiongetaddrinfo_positive(req){
+constoriginalResolve=req.resolve;
+req.reject=common.mustNotCall();
+req.resolve=common.mustCall(originalResolve);
+req.oncomplete(null,addresses);
+};
+}
+
+asyncfunctionlookupPositive(){
+[
+{
+stub: getaddrinfoPositive(['::1']),
+factory: ()=>dnsPromises.lookup('example.com'),
+expectation: {address: '::1',family: 6}
+},
+{
+stub: getaddrinfoPositive(['127.0.0.1']),
+factory: ()=>dnsPromises.lookup('example.com'),
+expectation: {address: '127.0.0.1',family: 4}
+},
+{
+stub: getaddrinfoPositive(['127.0.0.1'],{family: 4}),
+factory: ()=>dnsPromises.lookup('example.com'),
+expectation: {address: '127.0.0.1',family: 4}
+},
+{
+stub: getaddrinfoPositive(['some-address']),
+factory: ()=>dnsPromises.lookup('example.com'),
+expectation: {address: 'some-address',family: 0}
+},
+{
+stub: getaddrinfoPositive(['some-address2']),
+factory: ()=>dnsPromises.lookup('example.com',{family: 6}),
+expectation: {address: 'some-address2',family: 6}
+}
+].forEach(async({ stub, factory, expectation })=>{
+getaddrinfoStub=stub;
+assert.deepStrictEqual(awaitfactory(),expectation);
+});
+}
+
+asyncfunctionlookupNegative(){
+getaddrinfoStub=getaddrinfoNegative();
+constexpected={
+code: 'ENOMEM',
+hostname: 'example.com',
+syscall: 'getaddrinfo'
+};
+returnassert.rejects(dnsPromises.lookup('example.com'),expected);
+}
+
+asyncfunctionlookupallPositive(){
+[
+{
+stub: getaddrinfoPositive(['::1','::2']),
+factory: ()=>dnsPromises.lookup('example',{all: true}),
+expectation: [
+{address: '::1',family: 6},
+{address: '::2',family: 6}
+]
+},
+{
+stub: getaddrinfoPositive(['::1','::2']),
+factory: ()=>dnsPromises.lookup('example',{all: true,family: 4}),
+expectation: [
+{address: '::1',family: 4},
+{address: '::2',family: 4}
+]
+},
+{
+stub: getaddrinfoPositive(['127.0.0.1','some-address']),
+factory: ()=>dnsPromises.lookup('example',{all: true}),
+expectation: [
+{address: '127.0.0.1',family: 4},
+{address: 'some-address',family: 0}
+]
+},
+{
+stub: getaddrinfoPositive(['127.0.0.1','some-address']),
+factory: ()=>dnsPromises.lookup('example',{all: true,family: 6}),
+expectation: [
+{address: '127.0.0.1',family: 6},
+{address: 'some-address',family: 6}
+]
+},
+{
+stub: getaddrinfoPositive([]),
+factory: ()=>dnsPromises.lookup('example',{all: true}),
+expectation: []
+}
+].forEach(async({ stub, factory, expectation })=>{
+getaddrinfoStub=stub;
+assert.deepStrictEqual(awaitfactory(),expectation);
+});
+}
+
+asyncfunctionlookupallNegative(){
+getaddrinfoStub=getaddrinfoNegative();
+constexpected={
+code: 'ENOMEM',
+hostname: 'example.com',
+syscall: 'getaddrinfo'
+};
+returnassert.rejects(dnsPromises.lookup('example.com',{all: true}),
+expected);
+}
+
+(async()=>{
+awaitPromise.all([
+lookupPositive(),
+lookupNegative(),
+lookupallPositive(),
+lookupallNegative()
+]).then(common.mustCall());
+})();