How to differentiate between style and syntax errors?

[pstahlhofen]

I am new to ALE and my main goal for using this plugin is that I want to see syntax and name errors (such as undefined variables) in my Python code before actually running it. Adjusting my code according to style guides is not my main priority. In fact, some style recommendations (like the insertion of blank lines at many locations) might even hinder me because I have a visual impairment, hence I have to use a magnifier and only small portions of code fit on my screen at once.
I would like to find a way to fix ONLY the real errors and to make ALE showing me only those. This leads me to the following questions:

1. Is there a linter for Python that shows only syntax errors? If yes, how would I set up ALE to use this linter only.
2. If no such linter exists, could I navigate the error list of ALE and navigate automatically only to the places in my code where real errors occurred?
   Any answers would be very appreciated

[w0rp]

ALE linters can add a subtype key value for style to indicate if errors are warnings are for style or not. Wherever you see they don't, open issues for them or create pull requests. Check out :help ALEStyleError.

For disabling particular errors or warnings, configure the tool itself to do that with its own project files.

[pstahlhofen]

Alright, tank you!

[pstahlhofen]

@w0rp Could you tell me how to make ALE only highlight the errors that are not ALEStyleErrors? Is it possible to add only those errors to the loc-list?

[pstahlhofen]

@w0rp Okay, it seems like I found a solution now, so I'll write it down here for anyone else who is also looking for a linter only showing "real errors" for Python. Here's a step by step guide:

1. Install pylint (e.g. via conda install pylint)
2. Go to your ~/.vimrc and add the following lines:

let g:ale_linters={'python': ['pylint']}
let g:ale_linters_explicit=1

Those will make sure that ALE uses pylint and nothing else
3. Go to the place where you installed ale (in my case ~/.vim/pack/my_plugins/start). Navigate to ale/ale_linters/python and edit the file pylint.vim. Change the line

call ale#Set('python_pylint_options', '')

to

call ale#Set('python_pylint_options', '-E')

From now on, pylint will always be called with the -E option, making it only show real errors.