Can't Configure it Correctly

[husainaloos]

Hi,
I tried to install the package, and I added the python file in /usr/local/bin/. I added the following in my .emacs

(eval-after-load 'flycheck
    '(progn
       (require 'flycheck-google-cpplint)
       ;; Add Google C++ Style checker.
       ;; In default, syntax checked by Clang and Cppcheck.
       (flycheck-add-next-checker 'c/c++-cppcheck
                                  '(warnings-only . c/c++-googlelint))))
  (custom-set-variables
   '(flycheck-googlelint-verbose "3")
   '(flycheck-google-cpplint-command "/usr/local/bin/cpplint.py")
   '(flycheck-googlelint-filter "-whitespace,+whitespace/braces")
   '(flycheck-googlelint-root "project/src")
   '(flycheck-googlelint-linelength "120"))

and hooked it with my c++-mode-hook. All I get when I activate flycheck-mode is this:

Checker c/c++-googlelint returned non-zero exit code 1, but no errors from output: 
Checker definition probably flawed.

Any idea what's going on?

First:
I do not provide flycheck-google-cpplint-command option in flycheck version. That means, you have need to add /usr/local/bin to PATH environment. (see also: EmacsWiki: Exec Path)

Second:
If you not use cppcheck. You have need to change flycheck-add-next-checker.

(flycheck-add-next-checker 'c/c++-clang
                           '(warnings-only . c/c++-googlelint))

Please try above two points.

[swsnr]

@senda-akiha flycheck-google-cpplint-command is automatically declared by Flycheck. Changing this variable is sufficient to make Flycheck find cpplint.

Besides, the error message indicates that Flycheck actually runs cpplint, but is unable to parse it's output.

@husainaloos Can you try M-x flycheck-select-checker RET c/c++-googlelint and then C-c ! C-c in a C++ buffer? Flycheck should pop up a buffer which shows the entire output of googlelint. Can you paste that here?

[husainaloos]

@lunaryorn This is what I get

-*- mode: compilation; default-directory: "~/" -*-
Compilation started at Sun Mar 23 12:14:00

cpplint.py --verbose\=3 --filter\=-whitespace\,\+whitespace/braces --root\=project/src --linelength\=120 /home/husainaloos/test.cpp

Compilation exited abnormally with code 1 at Sun Mar 23 12:14:00

[swsnr]

@husainaloos Do you get the same result when your run this command on the terminal?

[husainaloos]

@lunaryorn Yes I do.

[husainaloos]

Hmm. I tried to update PATH, change the path in flycheck-google-cpplint.el file, change my configurations, but with no success.
Cppcheck works fine, but google-cpplint doesn't :/ I am still puzzled what's going on.

[husainaloos]

Update:

(1) I noticed that cpplint.py does not work. When I do cpplint.py test.cpp I do get nothing. So I downloaded cpplint from the repository directly instead. Now cpplint test.cpp outputs the error in test.cpp.

(2) I changed my .emacs and instead I added this:

  (flycheck-mode 1)                                                                                                                                           
  (eval-after-load 'flycheck                                                                                                                                  
    '(progn                                                                                                                                                   
       (require 'flycheck-google-cpplint)                                                                                                                     
       (flycheck-add-next-checker 'c/c++-cppcheck                                                                                                             
                                  'c/c++-googlelint 'append))) 

Which is what I found in my flycheck-google-cpplint.el file. I changed the cpplint.py to cpplint in my flycheck-google-cpplint.el as well.

Now when I run flycheck on test.cpp file I get the following error:

Error: (user-error "Configured syntax checker c/c++-googlelint cannot be used") 

Not sure where to go now...

[swsnr]

@husainaloos The value of flycheck-c/c++-cpplint-executable? Use C-h v to find out.

(custom-set-variables
 '(flycheck-c/c++-googlelint-executable "/usr/local/bin/cpplint.py"))

I did not know it would be able this.
I will add it to README.

[husainaloos]

@senda-akiha @lunaryorn Finally works! It seems that the value was set to nil for some reason.
Thanks!

Q: cpplint is applied to the .cpp file only when I save (it does not update the errors unless I save). is there a way to change that, to make it work as I type just like it does in flymake?

[swsnr]

@husainaloos Flycheck will automatically check the buffer after changes, i.e. work like Flymake. If it doesn't in your case, you've disabled it. Check the value of flycheck-check-syntax-automatically.

[husainaloos]

@lunaryorn The value is (save idle-change new-line mode-enabled), so that is fine.

cppcheck checks fine. It updates the errors and warning while editing the buffer. cpplint doesn't; i have to save the buffer in order for it to update. :/

[swsnr]

@husainaloos Indeed, this syntax checker uses source-original.

@senda-akiha Is there a reason why you use source-original instead of source or source-inplace in this syntax checker?

@lunaryorn
Reason that I use a source-original, because depends on the location of the file.

Examples:
Assuing that src/.git exists, the header guard CPP variables for
src/chrome/browser/ui/browser.h are:

    No flag => CHROME_BROWSER_UI_BROWSER_H_
    --root=chrome => BROWSER_UI_BROWSER_H_
    --root=chrome/browser => UI_BROWSER_H_