Format project with black (#467)

Format with line length 110 to match flake8

make black part of linting check

Update travis spec for updated black requirements

Add diff output for black on failure

update changelog

vcr/migration.py

@@ -38,55 +38,46 @@ def preprocess_yaml(cassette):
     # versions.  So this just strips the tags before deserializing.
 
     STRINGS_TO_NUKE = [
-        '!!python/object:vcr.request.Request',
-        '!!python/object/apply:__builtin__.frozenset',
-        '!!python/object/apply:builtins.frozenset',
+        "!!python/object:vcr.request.Request",
+        "!!python/object/apply:__builtin__.frozenset",
+        "!!python/object/apply:builtins.frozenset",
     ]
     for s in STRINGS_TO_NUKE:
-        cassette = cassette.replace(s, '')
+        cassette = cassette.replace(s, "")
     return cassette
 
 
-PARTS = [
-    'protocol',
-    'host',
-    'port',
-    'path',
-]
+PARTS = ["protocol", "host", "port", "path"]
 
 
 def build_uri(**parts):
-    port = parts['port']
-    scheme = parts['protocol']
-    default_port = {'https': 443, 'http': 80}[scheme]
-    parts['port'] = ':{}'.format(port) if port != default_port else ''
+    port = parts["port"]
+    scheme = parts["protocol"]
+    default_port = {"https": 443, "http": 80}[scheme]
+    parts["port"] = ":{}".format(port) if port != default_port else ""
     return "{protocol}://{host}{port}{path}".format(**parts)
 
 
 def _migrate(data):
     interactions = []
     for item in data:
-        req = item['request']
-        res = item['response']
+        req = item["request"]
+        res = item["response"]
         uri = {k: req.pop(k) for k in PARTS}
-        req['uri'] = build_uri(**uri)
+        req["uri"] = build_uri(**uri)
         # convert headers to dict of lists
-        headers = req['headers']
+        headers = req["headers"]
         for k in headers:
             headers[k] = [headers[k]]
         response_headers = {}
-        for k, v in get_httpmessage(
-            b"".join(h.encode('utf-8') for h in res['headers'])
-        ).items():
+        for k, v in get_httpmessage(b"".join(h.encode("utf-8") for h in res["headers"])).items():
             response_headers.setdefault(k, [])
             response_headers[k].append(v)
-        res['headers'] = response_headers
-        interactions.append({'request': req, 'response': res})
+        res["headers"] = response_headers
+        interactions.append({"request": req, "response": res})
     return {
-        'requests': [
-            request.Request._from_dict(i['request']) for i in interactions
-        ],
-        'responses': [i['response'] for i in interactions],
+        "requests": [request.Request._from_dict(i["request"]) for i in interactions],
+        "responses": [i["response"] for i in interactions],
     }
 
 
@@ -105,7 +96,7 @@ def _list_of_tuples_to_dict(fs):
 
 def _already_migrated(data):
     try:
-        if data.get('version') == 1:
+        if data.get("version") == 1:
             return True
     except AttributeError:
         return False
@@ -116,9 +107,7 @@ def migrate_yml(in_fp, out_fp):
     if _already_migrated(data):
         return False
     for i in range(len(data)):
-        data[i]['request']['headers'] = _list_of_tuples_to_dict(
-            data[i]['request']['headers']
-        )
+        data[i]["request"]["headers"] = _list_of_tuples_to_dict(data[i]["request"]["headers"])
     interactions = _migrate(data)
     out_fp.write(serialize(interactions, yamlserializer))
     return True
@@ -127,43 +116,42 @@ def migrate_yml(in_fp, out_fp):
 def migrate(file_path, migration_fn):
     # because we assume that original files can be reverted
     # we will try to copy the content. (os.rename not needed)
-    with tempfile.TemporaryFile(mode='w+') as out_fp:
-        with open(file_path, 'r') as in_fp:
+    with tempfile.TemporaryFile(mode="w+") as out_fp:
+        with open(file_path, "r") as in_fp:
             if not migration_fn(in_fp, out_fp):
                 return False
-        with open(file_path, 'w') as in_fp:
+        with open(file_path, "w") as in_fp:
             out_fp.seek(0)
             shutil.copyfileobj(out_fp, in_fp)
         return True
 
 
 def try_migrate(path):
-    if path.endswith('.json'):
+    if path.endswith(".json"):
         return migrate(path, migrate_json)
-    elif path.endswith('.yaml') or path.endswith('.yml'):
+    elif path.endswith(".yaml") or path.endswith(".yml"):
         return migrate(path, migrate_yml)
     return False
 
 
 def main():
     if len(sys.argv) != 2:
-        raise SystemExit("Please provide path to cassettes directory or file. "
-                         "Usage: python -m vcr.migration PATH")
+        raise SystemExit(
+            "Please provide path to cassettes directory or file. " "Usage: python -m vcr.migration PATH"
+        )
 
     path = sys.argv[1]
     if not os.path.isabs(path):
         path = os.path.abspath(path)
     files = [path]
     if os.path.isdir(path):
-        files = (os.path.join(root, name)
-                 for (root, dirs, files) in os.walk(path)
-                 for name in files)
+        files = (os.path.join(root, name) for (root, dirs, files) in os.walk(path) for name in files)
     for file_path in files:
         migrated = try_migrate(file_path)
-        status = 'OK' if migrated else 'FAIL'
+        status = "OK" if migrated else "FAIL"
         sys.stderr.write("[{}] {}\n".format(status, file_path))
     sys.stderr.write("Done.\n")
 
 
-if __name__ == '__main__':
+if __name__ == "__main__":
     main()