Handle mismatched network formats in config files

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

tests/acceptance/cli_test.py

@@ -185,7 +185,7 @@ class CLITestCase(DockerClientTestCase):
                     'build': {
                         'context': os.path.abspath(self.base_dir),
                     },
-                    'networks': ['front', 'default'],
+                    'networks': {'front': None, 'default': None},
                     'volumes_from': ['service:other:rw'],
                 },
                 'other': {

tests/integration/project_test.py

@@ -565,7 +565,7 @@ class ProjectTest(DockerClientTestCase):
                 'name': 'web',
                 'image': 'busybox:latest',
                 'command': 'top',
-                'networks': ['foo', 'bar', 'baz'],
+                'networks': {'foo': None, 'bar': None, 'baz': None},
             }],
             volumes={},
             networks={
@@ -598,7 +598,7 @@ class ProjectTest(DockerClientTestCase):
             services=[{
                 'name': 'web',
                 'image': 'busybox:latest',
-                'networks': ['front'],
+                'networks': {'front': None},
             }],
             volumes={},
             networks={

tests/unit/config/config_test.py

@@ -649,6 +649,42 @@ class ConfigTest(unittest.TestCase):
         assert service['build']['args']['opt1'] == '42'
         assert service['build']['args']['opt2'] == 'foobar'
 
+    def test_load_with_multiple_files_mismatched_networks_format(self):
+        base_file = config.ConfigFile(
+            'base.yaml',
+            {
+                'version': '2',
+                'services': {
+                    'web': {
+                        'image': 'example/web',
+                        'networks': {
+                            'foobar': {'aliases': ['foo', 'bar']}
+                        }
+                    }
+                },
+                'networks': {'foobar': {}, 'baz': {}}
+            }
+        )
+
+        override_file = config.ConfigFile(
+            'override.yaml',
+            {
+                'version': '2',
+                'services': {
+                    'web': {
+                        'networks': ['baz']
+                    }
+                }
+            }
+        )
+
+        details = config.ConfigDetails('.', [base_file, override_file])
+        web_service = config.load(details).services[0]
+        assert web_service['networks'] == {
+            'foobar': {'aliases': ['foo', 'bar']},
+            'baz': None
+        }
+
     def test_load_with_multiple_files_v2(self):
         base_file = config.ConfigFile(
             'base.yaml',

tests/unit/project_test.py

@@ -438,7 +438,7 @@ class ProjectTest(unittest.TestCase):
                     {
                         'name': 'foo',
                         'image': 'busybox:latest',
-                        'networks': ['custom']
+                        'networks': {'custom': None}
                     },
                 ],
                 networks={'custom': {}},