Re-enable pid_mode checks for API < 1.24

Signed-off-by: Joffrey F <joffrey@docker.com>

docker/utils/utils.py

@@ -736,6 +736,8 @@ def create_host_config(binds=None, port_bindings=None, lxc_conf=None,
         host_config['ShmSize'] = shm_size
 
     if pid_mode:
+        if version_lt(version, '1.24') and pid_mode != 'host':
+            raise host_config_value_error('pid_mode', pid_mode)
         host_config['PidMode'] = pid_mode
 
     if ipc_mode:

tests/integration/api_container_test.py

@@ -361,10 +361,6 @@ class CreateContainerTest(BaseAPIIntegrationTest):
         host_config = inspect['HostConfig']
         self.assertIn('MemorySwappiness', host_config)
 
-    def test_create_host_config_exception_raising(self):
-        self.assertRaises(TypeError,
-                          self.client.create_host_config, mem_swappiness='40')
-
     def test_create_with_environment_variable_no_value(self):
         container = self.client.create_container(
             BUSYBOX,

tests/unit/utils_test.py

@@ -205,6 +205,19 @@ class HostConfigTest(unittest.TestCase):
                 version='1.24', isolation={'isolation': 'hyperv'}
             )
 
+    def test_create_host_config_pid_mode(self):
+        with pytest.raises(ValueError):
+            create_host_config(version='1.23', pid_mode='baccab125')
+
+        config = create_host_config(version='1.23', pid_mode='host')
+        assert config.get('PidMode') == 'host'
+        config = create_host_config(version='1.24', pid_mode='baccab125')
+        assert config.get('PidMode') == 'baccab125'
+
+    def test_create_host_config_invalid_mem_swappiness(self):
+        with pytest.raises(TypeError):
+            create_host_config(version='1.24', mem_swappiness='40')
+
 
 class UlimitTest(unittest.TestCase):
     def test_create_host_config_dict_ulimit(self):