Please help: pylint does not work with Emacs23

Question

Hi,

I am trying to use Pylint with Emacs on Windows XP. My Emacs version is EmacsW32 23.1, pylint is 0.21.3 with Python 2.5. After easy_install pylint, I added the following lines to Emacs init file, copied form Emacs Wiki.

When I invoke the flymake-mode on a .py file, I can see the flymake starting the syntax check, the mode status changed to flymake*, and then goes back to flymake after several seconds. But no error is reported, and no syntax error highlighting.

I tried to use pylint in command line, and it works with command "pylint test.py", reporting syntax errors on the same file.

I even tried to clear out my .emacs file, but it doesn't help.

Could someone help me on this? Thanks a lot.

(when (load "flymake" t)
  (defun flymake-pylint-init ()
    (let* ((temp-file (flymake-init-create-temp-buffer-copy
                       'flymake-create-temp-inplace))
       (local-file (file-relative-name
                    temp-file
                    (file-name-directory buffer-file-name))))
      (list "epylint" (list local-file))))

  (add-to-list 'flymake-allowed-file-name-masks
           '("\\.py\\'" flymake-pylint-init)))

Question Update: I tried the following at command line prompt with "pylint" and "epylint". Does this mean epylint has a problem?

C:\Projects>pylint test_lib.py
No config file found, using default configuration
************* Module test_lib
E: 13: invalid syntax

C:\Projects>epylint test_lib.py
'test_lib.py':1: [F] No module named 'test_lib.py'

C:\Projects>epylint
Traceback (most recent call last):
  File "C:\Python25\Scripts\epylint", line 5, in <module>
    pkg_resources.run_script('pylint==0.21.3', 'epylint')
  File "C:\Python25\Lib\site-packages\pkg_resources.py", line 489, in run_script

    self.require(requires)[0].run_script(script_name, ns)
  File "C:\Python25\Lib\site-packages\pkg_resources.py", line 1207, in run_script
    execfile(script_filename, namespace, namespace)
  File "c:\python25\lib\site-packages\pylint-0.21.3-py2.5.egg\EGG-INFO\scripts\epylint", line 3, in <module>
    epylint.Run()
  File "c:\python25\lib\site-packages\pylint-0.21.3-py2.5.egg\pylint\epylint.py", line 93, in Run
    lint(sys.argv[1])
IndexError: list index out of range

Answer 1

I use emacs22-nox on linux so you may need to google "font-lock-mode" to figure out how to do it on your computer. First enter the emacs command line by pressing Esc+x. Now you can type font-lock-mode and hit enter (the command line is at the bottom of the screen). I had the same problem on one my clients servers. Their emacs didn't turn font-lock-mode on by default. Hope that helps.

Answer 2

The program called by flymake should return 0 errorlevel or else flymake thinks there have been problems calling subprocesses.

Reading this answer and those patches, I have managed to run flymake with pylint :

On Windows, but you could do the same kind of thing on Un*x, I have created a batch file pycheckers.bat (accessible in your PATH) :

pylint -f parseable -r n --disable=C,R,I %1 %2 %3 %4 %5 %6 %7 %8 %9
exit /b 0

In my .emacs, I have put those lines :

(when (load "flymake" t)
  (defun flymake-pyflakes-init ()
    (let* ((temp-file (flymake-init-create-temp-buffer-copy
                       'flymake-create-temp-inplace))
           (local-file (file-relative-name
                        temp-file
                        (file-name-directory buffer-file-name))))
      (list "pycheckers"  (list local-file))))
  (add-to-list 'flymake-allowed-file-name-masks
               '("\\.py\\'" flymake-pyflakes-init)))

Now, when I open a .py file, I do a M-x flymake-mode to activate it. Flymake finds my python errors and warnings without problem.

Note that you can add other tools in the pycheckers.bat file.

Answer 3

I tried Jerome's answer on Ergoemacs and it works. The problem is as he said: Pylint returns non 0 errorlevel as it uses the errorlevel to give information about problems. I wanted to vote up Jerome's answer but I don't have any reputation.