old_contents: import pytest
  import mock
  
  from datadog_checks.checks import AgentCheck
  from datadog_checks.ping import PingCheck
  from datadog_checks.errors import CheckException
  
  
  def mock_exec_ping():
      return """FAKEPING 127.0.0.1 (127.0.0.1): 56 data bytes
  64 bytes from 127.0.0.1: icmp_seq=0 ttl=64 time=0.093 ms
  
  --- 127.0.0.1 ping statistics ---
  1 packets transmitted, 1 packets received, 0.0% packet loss
  round-trip min/avg/max/stddev = 0.093/0.093/0.093/0.000 ms"""
  
  
  def test_check(aggregator, instance):
      c = PingCheck('ping', {}, {})
  
      # empty instance
      instance = {}
      with pytest.raises(CheckException):
          c.check(instance)
  
      # only name
      with pytest.raises(CheckException):
          c.check({'name': 'Datadog'})
  
      test_check
      # good check
      instance = {
          'host': '127.0.0.1',
          'name': "Localhost"
      }
  
      with mock.patch.object(c, "_exec_ping", return_value=mock_exec_ping()):
          c.check(instance)
      aggregator.assert_service_check('network.ping.can_connect', AgentCheck.OK)
  
new_contents: import pytest
  import mock
  
  from datadog_checks.checks import AgentCheck
  from datadog_checks.ping import PingCheck
  from datadog_checks.errors import CheckException
  
  
  def mock_exec_ping():
      return """FAKEPING 127.0.0.1 (127.0.0.1): 56 data bytes
  64 bytes from 127.0.0.1: icmp_seq=0 ttl=64 time=0.093 ms
  
  --- 127.0.0.1 ping statistics ---
  1 packets transmitted, 1 packets received, 0.0% packet loss
  round-trip min/avg/max/stddev = 0.093/0.093/0.093/0.000 ms"""
  
  
  def test_check(aggregator, instance):
      c = PingCheck('ping', {}, {})
  
      # empty instance
      instance = {}
      with pytest.raises(CheckException):
          c.check(instance)
  
      # only name
      with pytest.raises(CheckException):
          c.check({'name': 'Datadog'})
  
      test_check
      # good check
      instance = {
          'host': '127.0.0.1',
          'name': "Localhost"
      }
  
      with mock.patch.object(c, "_exec_ping", return_value=mock_exec_ping()):
          c.check(instance)
      aggregator.assert_service_check('network.ping.can_connect', AgentCheck.OK)
      aggregator.assert_metric('network.ping.can_connect', value=1)
  
subject: Update test to assert metric