Fix assert_hostname logic in tls_config_from_options

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

tests/unit/cli/docker_client_test.py

@@ -103,3 +103,31 @@ class TLSConfigTestCase(unittest.TestCase):
         options = {'--tlskey': self.key}
         with pytest.raises(docker.errors.TLSParameterError):
             tls_config_from_options(options)
+
+    def test_assert_hostname_explicit_host(self):
+        options = {
+            '--tlscacert': self.ca_cert, '--host': 'tcp://foobar.co.uk:1254'
+        }
+        result = tls_config_from_options(options)
+        assert isinstance(result, docker.tls.TLSConfig)
+        assert result.assert_hostname == 'foobar.co.uk'
+
+    def test_assert_hostname_explicit_host_no_proto(self):
+        options = {
+            '--tlscacert': self.ca_cert, '--host': 'foobar.co.uk:1254'
+        }
+        result = tls_config_from_options(options)
+        assert isinstance(result, docker.tls.TLSConfig)
+        assert result.assert_hostname == 'foobar.co.uk'
+
+    def test_assert_hostname_implicit_host(self):
+        options = {'--tlscacert': self.ca_cert}
+        result = tls_config_from_options(options)
+        assert isinstance(result, docker.tls.TLSConfig)
+        assert result.assert_hostname is None
+
+    def test_assert_hostname_explicit_skip(self):
+        options = {'--tlscacert': self.ca_cert, '--skip-hostname-check': True}
+        result = tls_config_from_options(options)
+        assert isinstance(result, docker.tls.TLSConfig)
+        assert result.assert_hostname is False