Fix E302 false negative in presence of decorators.

pycodestyle.py

@@ -358,14 +358,15 @@ def blank_lines(logical_line, blank_lines, indent_level, line_number,
           ):
         yield 0, "E303 too many blank lines (%d)" % blank_lines
     elif STARTSWITH_TOP_LEVEL_REGEX.match(logical_line):
-        # If this is a one-liner (i.e. the next line is not more
-        # indented), and the previous line is also not deeper
-        # (it would be better to check if the previous line is part
-        # of another def/class at the same level), don't require blank
-        # lines around this.
+        # If this is a one-liner (i.e. this is not a decorator and the
+        # next line is not more indented), and the previous line is also
+        # not deeper (it would be better to check if the previous line
+        # is part of another def/class at the same level), don't require
+        # blank lines around this.
         prev_line = lines[line_number - 2] if line_number >= 2 else ''
         next_line = lines[line_number] if line_number < len(lines) else ''
-        if (expand_indent(prev_line) <= indent_level and
+        if (not logical_line.startswith("@") and
+                expand_indent(prev_line) <= indent_level and
                 expand_indent(next_line) <= indent_level):
             return
         if indent_level:

testsuite/E30.py

@@ -181,3 +181,11 @@ def foo():
     def bar(): pass
     def baz():
         pass
+#: E302:5:1
+def f():
+    pass
+
+# wat
+@hi
+def g():
+    pass