text: // Test the behavior when two users from the same database are authenticated serially on a single
  // connection.  Expected behavior is that the first user is implicitly logged out by the second
  // authentication.
  //
  // Regression test for SERVER-8144.
  var conn = MongoRunner.runMongod({auth: "", smallfiles: ""});
  var admin = conn.getDB("admin");
  var test = conn.getDB("test");
  
  admin.createUser({user: 'admin', pwd: 'a', roles: jsTest.adminUserRoles});
  assert(admin.auth('admin', 'a'));
  test.createUser({user: 'reader', pwd: 'a', roles: ["read"]});
  test.createUser({user: 'writer', pwd: 'a', roles: ["readWrite"]});
  admin.logout();
  
  // Nothing logged in, can neither read nor write.
  assert.writeError(test.docs.insert({value: 0}));
  assert.throws(function() {
      test.foo.findOne();
  });
  
  // Writer logged in, can read and write.
  test.auth('writer', 'a');
  assert.writeOK(test.docs.insert({value: 1}));
  test.foo.findOne();
  
  // Reader logged in, replacing writer, can only read.
  test.auth('reader', 'a');
  assert.writeError(test.docs.insert({value: 2}));
  test.foo.findOne();
  