Require two blank lines after toplevel def/class; issue PyCQA#400

Author: benesch

pep8.py

@@ -234,7 +234,8 @@ def maximum_line_length(physical_line, max_line_length, multiline):
 
 
 def blank_lines(logical_line, blank_lines, indent_level, line_number,
-                blank_before, previous_logical, previous_indent_level):
+                blank_before, previous_logical, previous_logical_toplevel,
+                previous_indent_level):
     r"""Separate top-level function and class definitions with two blank lines.
 
     Method definitions inside a class are separated by a single blank line.
@@ -253,6 +254,7 @@ def blank_lines(logical_line, blank_lines, indent_level, line_number,
     E303: def a():\n    pass\n\n\n\ndef b(n):\n    pass
     E303: def a():\n\n\n\n    pass
     E304: @decorator\n\ndef a():\n    pass
+    E305: def a():\n    pass\na()
     """
     if line_number < 3 and not previous_logical:
         return  # Don't expect blank lines before the first line
@@ -268,6 +270,9 @@ def blank_lines(logical_line, blank_lines, indent_level, line_number,
                 yield 0, "E301 expected 1 blank line, found 0"
         elif blank_before != 2:
             yield 0, "E302 expected 2 blank lines, found %d" % blank_before
+    elif (logical_line and not indent_level and blank_before != 2 and
+          previous_logical_toplevel.startswith(('def', 'class'))):
+        yield 0, "E305 expected 2 blank lines before, found %d" % blank_before
 
 
 def extraneous_whitespace(logical_line):
@@ -1497,6 +1502,8 @@ def check_logical(self):
         if self.logical_line:
             self.previous_indent_level = self.indent_level
             self.previous_logical = self.logical_line
+            if not self.indent_level:
+                self.previous_logical_toplevel = self.logical_line
         self.blank_lines = 0
         self.tokens = []
 
@@ -1566,6 +1573,7 @@ def check_all(self, expected=None, line_offset=0):
         self.indent_char = None
         self.indent_level = self.previous_indent_level = 0
         self.previous_logical = ''
+        self.previous_logical_toplevel = ''
         self.tokens = []
         self.blank_lines = self.blank_before = 0
         parens = 0

testsuite/E30.py

@@ -88,3 +88,32 @@ def function():
 It gives error E303: too many blank lines (3)
 """
 #:
+
+#: E305:7:1
+def a():
+    print
+
+    # comment
+
+    # another comment
+a()
+#: E305:8:1
+def a():
+    print
+
+    # comment
+
+    # another comment
+
+try:
+    a()
+except:
+    pass
+#: E305:5:1
+def a():
+    print
+
+# Two spaces before comments, too.
+if a():
+    a()
+#: