Correct lint errors and silence W504

mypy/binder.py

@@ -110,10 +110,10 @@ def push_frame(self) -> Frame:
         self.options_on_return.append([])
         return f
 
-    def _put(self, key: Key, type: Type, index: int=-1) -> None:
+    def _put(self, key: Key, type: Type, index: int = -1) -> None:
         self.frames[index].types[key] = type
 
-    def _get(self, key: Key, index: int=-1) -> Optional[Type]:
+    def _get(self, key: Key, index: int = -1) -> Optional[Type]:
         if index < 0:
             index += len(self.frames)
         for i in range(index, -1, -1):

mypy/build.py

@@ -865,7 +865,7 @@ def atomic_write(filename: str, line1: str, line2: str) -> bool:
             for line in lines:
                 f.write(line)
         os.replace(tmp_filename, filename)
-    except os.error as err:
+    except os.error:
         return False
     return True
 

mypy/dmypy.py

@@ -151,7 +151,7 @@ def do_start(args: argparse.Namespace) -> None:
     """
     try:
         get_status()
-    except BadStatus as err:
+    except BadStatus:
         # Bad or missing status file or dead process; good to start.
         pass
     else:
@@ -435,7 +435,7 @@ def check_status(data: Dict[str, Any]) -> Tuple[int, str]:
         raise BadStatus("pid field is not an int")
     try:
         os.kill(pid, 0)
-    except OSError as err:
+    except OSError:
         raise BadStatus("Daemon has died")
     if 'sockname' not in data:
         raise BadStatus("Invalid status file (no sockname field)")
@@ -456,7 +456,7 @@ def read_status() -> Dict[str, object]:
     with open(STATUS_FILE) as f:
         try:
             data = json.load(f)
-        except Exception as err:
+        except Exception:
             raise BadStatus("Malformed status file (not JSON)")
     if not isinstance(data, dict):
         raise BadStatus("Invalid status file (not a dict)")
@@ -467,7 +467,7 @@ def is_running() -> bool:
     """Check if the server is running cleanly"""
     try:
         get_status()
-    except BadStatus as err:
+    except BadStatus:
         return False
     return True
 

mypy/dmypy_server.py

@@ -170,7 +170,7 @@ def serve(self) -> None:
                         sys.exit(0)
                     try:
                         data = receive(conn)
-                    except OSError as err:
+                    except OSError:
                         conn.close()  # Maybe the client hung up
                         continue
                     resp = {}  # type: Dict[str, Any]
@@ -192,7 +192,7 @@ def serve(self) -> None:
                                 raise
                     try:
                         conn.sendall(json.dumps(resp).encode('utf8'))
-                    except OSError as err:
+                    except OSError:
                         pass  # Maybe the client hung up
                     conn.close()
                     if command == 'stop':

mypy/nodes.py

@@ -1917,7 +1917,7 @@ class TypeVarExpr(SymbolNode, Expression):
     def __init__(self, name: str, fullname: str,
                  values: List['mypy.types.Type'],
                  upper_bound: 'mypy.types.Type',
-                 variance: int=INVARIANT) -> None:
+                 variance: int = INVARIANT) -> None:
         super().__init__()
         self._name = name
         self._fullname = fullname

mypy/solve.py

@@ -11,7 +11,7 @@
 
 
 def solve_constraints(vars: List[TypeVarId], constraints: List[Constraint],
-                      strict: bool =True) -> List[Optional[Type]]:
+                      strict: bool = True) -> List[Optional[Type]]:
     """Solve type constraints.
 
     Return the best type(s) for type variables; each type can be None if the value of the variable

mypy/stubgen.py

@@ -348,7 +348,7 @@ def add_import_from(self, module: str, names: List[Tuple[str, Optional[str]]]) -
             if alias:
                 self.reverse_alias[alias] = name
 
-    def add_import(self, module: str, alias: Optional[str]=None) -> None:
+    def add_import(self, module: str, alias: Optional[str] = None) -> None:
         name = module.split('.')[0]
         self.module_for[alias or name] = None
         self.direct_imports[name] = module
@@ -625,7 +625,7 @@ def process_namedtuple(self, lvalue: NameExpr, rvalue: CallExpr) -> None:
         self.add('%s = namedtuple(%s, %s)\n' % (lvalue.name, name, items))
         self._state = CLASS
 
-    def is_type_expression(self, expr: Expression, top_level: bool=True) -> bool:
+    def is_type_expression(self, expr: Expression, top_level: bool = True) -> bool:
         """Return True for things that look like type expressions
 
         Used to know if assignments look like typealiases
@@ -994,7 +994,7 @@ def default_python2_interpreter() -> str:
     raise SystemExit("Can't find a Python 2 interpreter -- please use the -p option")
 
 
-def usage(exit_nonzero: bool=True) -> None:
+def usage(exit_nonzero: bool = True) -> None:
     usage = textwrap.dedent("""\
         usage: stubgen [--py2] [--no-import] [--doc-dir PATH]
                        [--search-path PATH] [-p PATH] [-o PATH]

mypy/test/data.py

@@ -479,7 +479,7 @@ def expand_errors(input: List[str], output: List[str], fnam: str) -> None:
         # The first in the split things isn't a comment
         for possible_err_comment in input[i].split(' # ')[1:]:
             m = re.search(
-                '^([ENW]):((?P<col>\d+):)? (?P<message>.*)$',
+                r'^([ENW]):((?P<col>\d+):)? (?P<message>.*)$',
                 possible_err_comment.strip())
             if m:
                 if m.group(1) == 'E':
@@ -572,11 +572,11 @@ def split_test_cases(parent: 'DataSuiteCollector', suite: 'DataSuite',
     """
     with open(file, encoding='utf-8') as f:
         data = f.read()
-    cases = re.split('^\[case ([a-zA-Z_0-9]+)'
-                     '(-writescache)?'
-                     '(-only_when_cache|-only_when_nocache)?'
-                     '(-skip)?'
-                     '\][ \t]*$\n', data,
+    cases = re.split(r'^\[case ([a-zA-Z_0-9]+)'
+                     r'(-writescache)?'
+                     r'(-only_when_cache|-only_when_nocache)?'
+                     r'(-skip)?'
+                     r'\][ \t]*$\n', data,
                      flags=re.DOTALL | re.MULTILINE)
     line_no = cases[0].count('\n') + 1
     for i in range(1, len(cases), 5):

mypy/test/testmerge.py

@@ -114,7 +114,7 @@ def build(self, source: str) -> Optional[BuildResult]:
             result = build.build(sources=[BuildSource(main_path, None, None)],
                                  options=options,
                                  alt_lib_path=test_temp_dir)
-        except CompileError as e:
+        except CompileError:
             # TODO: Is it okay to return None?
             return None
         return result

mypy/test/typefixture.py

@@ -20,7 +20,7 @@ class TypeFixture:
     The members are initialized to contain various type-related values.
     """
 
-    def __init__(self, variance: int=COVARIANT) -> None:
+    def __init__(self, variance: int = COVARIANT) -> None:
         # The 'object' class
         self.oi = self.make_type_info('builtins.object')               # class object
         self.o = Instance(self.oi, [])                        # object

mypy/util.py

@@ -209,7 +209,7 @@ def get_class_descriptors(cls: 'Type[object]') -> Sequence[str]:
     return fields_cache[cls]
 
 
-def replace_object_state(new: object, old: object, copy_dict: bool=False) -> None:
+def replace_object_state(new: object, old: object, copy_dict: bool = False) -> None:
     """Copy state of old node to the new node.
 
     This handles cases where there is __dict__ and/or attribute descriptors

setup.cfg

@@ -35,12 +35,13 @@ exclude =
 #   W601: has_key() deprecated (false positives)
 #   E701: multiple statements on one line (colon) (we use this for classes with empty body)
 #   W503: line break before binary operator
+#   W504: line break after binary operator
 #   E704: multiple statements on one line (def)
 #   E402: module level import not at top of file
 #   B3??: Python 3 compatibility warnings
 #   B006: use of mutable defaults in function signatures
 #   B007: Loop control variable not used within the loop body.
-ignore = E251,E128,F401,W601,E701,W503,E704,E402,B3,B006,B007
+ignore = E251,E128,F401,W601,E701,W503,W504,E704,E402,B3,B006,B007
 
 [coverage:run]
 branch = true