Report E704 for async def as well (#611)

Fix detection of 'async  def' (with multiple spaces) so that it also reports E704

Author: asottile

pycodestyle.py

@@ -121,6 +121,8 @@
 OPERATOR_REGEX = re.compile(r'(?:[^,\s])(\s*)(?:[-+*/|!<=>%&^]+)(\s*)')
 LAMBDA_REGEX = re.compile(r'\blambda\b')
 HUNK_REGEX = re.compile(r'^@@ -\d+(?:,\d+)? \+(\d+)(?:,(\d+))? @@.*$')
+STARTSWITH_DEF_REGEX = re.compile(r'^(async\s+def|def)')
+STARTSWITH_TOP_LEVEL_REGEX = re.compile(r'^(async\s+def|def|class|@)')
 
 # Work around Python < 2.6 behaviour, which does not generate NL after
 # a comment which is on a line by itself.
@@ -272,7 +274,7 @@ def blank_lines(logical_line, blank_lines, indent_level, line_number,
             yield 0, "E304 blank lines found after function decorator"
     elif blank_lines > 2 or (indent_level and blank_lines == 2):
         yield 0, "E303 too many blank lines (%d)" % blank_lines
-    elif logical_line.startswith(('def ', 'async def', 'class ', '@')):
+    elif STARTSWITH_TOP_LEVEL_REGEX.match(logical_line):
         if indent_level:
             if not (blank_before or previous_indent_level < indent_level or
                     DOCSTRING_REGEX.match(previous_logical)):
@@ -813,7 +815,7 @@ def whitespace_around_named_parameter_equals(logical_line, tokens):
     no_space = False
     prev_end = None
     annotated_func_arg = False
-    in_def = logical_line.startswith(('def', 'async def'))
+    in_def = bool(STARTSWITH_DEF_REGEX.match(logical_line))
     message = "E251 unexpected spaces around keyword / parameter equals"
     for token_type, text, start, end, line in tokens:
         if token_type == tokenize.NL:
@@ -1000,7 +1002,7 @@ def compound_statements(logical_line):
                     yield 0, ("E731 do not assign a lambda expression, use a "
                               "def")
                 break
-            if line.startswith('def '):
+            if STARTSWITH_DEF_REGEX.match(line):
                 yield 0, "E704 multiple statements on one line (def)"
             else:
                 yield found, "E701 multiple statements on one line (colon)"

testsuite/E25.py

@@ -38,3 +38,7 @@ def munge(input: AnyStr, sep: AnyStr = None, limit=1000,
 #: Okay
 async def add(a: int = 0, b: int = 0) -> int:
     return a + b
+# Previously E251 four times
+#: E272:1:6
+async  def add(a: int = 0, b: int = 0) -> int:
+    return a + b

testsuite/E30.py

@@ -156,3 +156,10 @@ def main():
 
 if __name__ == '__main__':
     main()
+# Previously just E272:1:6 E272:4:6
+#: E302:4:1 E272:1:6 E272:4:6
+async  def x():
+    pass
+
+async  def x(y: int = 1):
+    pass

testsuite/E70.py

@@ -12,6 +12,10 @@
 del a[:]; a.append(42);
 #: E704:1:1
 def f(x): return 2
+#: E704:1:1
+async def f(x): return 2
+#: E704:1:1 E272:1:6
+async  def f(x): return 2
 #: E704:1:1 E226:1:19
 def f(x): return 2*x
 #: E704:2:5 E226:2:23