Fix #667 - Do not add extra blank lines for add_blank_lines_for_python_control_statements

autoload/ale/fixers/generic_python.vim

@@ -5,17 +5,20 @@
 function! ale#fixers#generic_python#AddLinesBeforeControlStatements(buffer, lines) abort
     let l:new_lines = []
     let l:last_indent_size = 0
+    let l:last_line_is_blank = 0
 
     for l:line in a:lines
         let l:indent_size = len(matchstr(l:line, '^ *'))
 
-        if l:indent_size <= l:last_indent_size
+        if !l:last_line_is_blank
+        \&& l:indent_size <= l:last_indent_size
         \&& match(l:line, '\v^ *(return|if|for|while|break|continue)') >= 0
             call add(l:new_lines, '')
         endif
 
         call add(l:new_lines, l:line)
         let l:last_indent_size = l:indent_size
+        let l:last_line_is_blank = empty(split(l:line))
     endfor
 
     return l:new_lines

test/fixers/test_python_add_blank_lines_fixer.vader

@@ -83,3 +83,29 @@ Expect python(Newlines should be added):
           pass
       else:
           pass
+
+Given python(A file with a main block):
+  import os
+
+
+  def main():
+      print('hello')
+
+
+  if __name__ == '__main__':
+      main()
+
+Execute(Fix the file):
+  let g:ale_fixers = {'python': ['add_blank_lines_for_python_control_statements']}
+  ALEFix
+
+Expect python(extra newlines shouldn't be added to the main block):
+  import os
+
+
+  def main():
+      print('hello')
+
+
+  if __name__ == '__main__':
+      main()