text: // Copyright Joyent, Inc. and other Node contributors.
  //
  // Permission is hereby granted, free of charge, to any person obtaining a
  // copy of this software and associated documentation files (the
  // "Software"), to deal in the Software without restriction, including
  // without limitation the rights to use, copy, modify, merge, publish,
  // distribute, sublicense, and/or sell copies of the Software, and to permit
  // persons to whom the Software is furnished to do so, subject to the
  // following conditions:
  //
  // The above copyright notice and this permission notice shall be included
  // in all copies or substantial portions of the Software.
  //
  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  // OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
  // NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
  // DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  // USE OR OTHER DEALINGS IN THE SOFTWARE.
  
  var common = require('../common');
  var assert = require('assert');
  
  var dns = require('dns');
  
  
  // Try resolution without callback
  
  dns.lookup(null, function(error, result, addressType) {
    assert.equal(null, result);
    assert.equal(4, addressType);
  });
  
  dns.lookup('127.0.0.1', function(error, result, addressType) {
    assert.equal('127.0.0.1', result);
    assert.equal(4, addressType);
  });
  
  dns.lookup('::1', function(error, result, addressType) {
    assert.equal('::1', result);
    assert.equal(6, addressType);
  });
  
  // Try calling resolve with an unsupported type.
  assert.throws(function() {
    dns.resolve('www.google.com', 'HI');
  }, /Unknown type/);
  
  // Windows doesn't usually have an entry for localhost 127.0.0.1 in
  // C:\Windows\System32\drivers\etc\hosts
  // so we disable this test on Windows.
  if (process.platform != 'win32') {
    dns.resolve('127.0.0.1', 'PTR', function(error, domains) {
      if (error) throw error;
      assert.ok(Array.isArray(domains));
    });
  }
  