Vim - Troubleshooting


in my case problem was with invalid .rubocop.yml file. this can be easily checked by running rubocop in the project root: if rubocop starts analyzing your project then all is fine otherwise it complains about invalid syntax - in that case just follow on-screen instructions and fix .rubocop.yml.

to debug inside Vim turn on syntastic debugging messages in command-line mode:

:let g:syntastic_debug = 1 " or 3 or 33

run syntastic checkers:

:SyntasticCheck mri rubocop

view syntastic debugging messages in Vim messages:


in my case rubocop returned status code 2 which means running rubocop checker failed on rubocop side.

BTW always set path to ruby and rubocop executables manually so as not to rely on correct PATH inside Vim (it can be messed up for a million reasons):

let g:syntastic_ruby_mri_exec = '~/.rbenv/shims/ruby'
let g:syntastic_ruby_rubocop_exec = '~/.rbenv/shims/rubocop'

[MacVim] blank screen on macOS Sierra and above

the problem didn’t exist in El Capitan - it first appeared in Sierra: the whole screen went blank when starting to move a cursor around.


# ~/.zlogin

defaults write org.vim.MacVim MMUseCGLayerAlways 1

UPDATE (2018-11-29)

this fix seems to be no longer required on macOS Mojave and MacVim 8.1-151_2 (maybe previous MacVim versions work too or maybe it’s all about new macOS).

…Mojave change that made all NSView automatically become layer-backed

iTerm2 and MacVim hang when running ALE

this happens only when file is saved several times in quick succession AND htop is opened in iTerm2 (or another terminal) - it freezes both iTerm2 and MacVim somehow.


this is a known bug in htop, macOS High Sierra or both:

UPDATE 2018-02-26

htop 2.0.2 is back in brew even though the issue is still open.

location list becomes blank after opening Markdown file

this happens when trying to open some Markdown files from location list with search results.


the problem is not Markdown-specific and is caused by ALE linting first opened files (g:ale_lint_on_enter option is enabled by default): after running linters ALE populates location list of current window with found issues (or just clears it if no issues are found) - anyway the previous contents of location list (search results) are gone.

to circumvent this problem it’s possible:

when using mouse, cursor is positioned with noticeable lag

this might be caused by source code tooltips (balloons) - disable them:

" ~/.vim/vimrc

set noballooneval

for Ruby it’s also necessary to unset balloonexpr ftplugin file:

" ftplugin/ruby.vim

setlocal balloonexpr=

creating alternate file doesn’t work

after running :AV command (same as :confirm A) there is no prompt to create alternate file if it’s missing:

E345: Can't find file "/Users/tap/dev/sith/spec/controllers/webhooks_controller_spec.rb" in path



I created new Rails project with --no-skip-test => test directory was created instead of spec one and vim-rails plugin couldn’t find or create alternate file. so just rename directory to fix the issue.

incorrect folding of lines with equal indent

" ~/.vim/vimrc

set foldmethod=indent

lines with equal indent don’t form a fold - folding stops at blank line.


If I’ve reproduced the problem and run :set shiftwidth=2 after the text has already been input, it works as expected but not if i do :set shiftwidth=2 before the text has been input. Similarly if the file has been saved and reopened, the shiftwidth=2 in .vimrc works and the fold works as expected.

all in all if folding is somehow broken, just reload file with :e command.

poor performance of Vim in the terminal on macOS

scrolling, moving cursor around - everything feels very slow.



macOS + tmux + vim is slow! I thought this was supposed to be fast!

This appears to be an issue outside of terminal emulators; either macOS has an IPC performance issue, or either tmux or vim (or both) have a bug. This same issue can be seen in iTerm2 and I’ve found that if tmux is running on another machine which is connected to Alacritty via SSH, this issue disappears. Actual throughput and rendering performance are still better in Alacritty.

P.S. MacVim’s version of Vim (mvim -v) runs a little bit faster.