by Ingo Karkat
This plugin highlights whitespace at the end of each line (except when typing at the end of a line). It uses the matchadd()-function, therefore doesn't interfere with syntax highlighting and leaves the :match command for other uses. Highlighting can be switched on/off globally and for individual buffers. The plugin comes with exceptions for certain filetypes, where certain lines can / must include trailing whitespace; additional patterns can be configured.
Many plugins also come with a command to strip off the trailing whitespace; this plugin separates this into the companion DeleteTrailingWhitespace.vim plugin (vimscript #3967), which can even remove the trailing whitespace automatically on each write.
To quickly locate the occurrences of trailing whitespace, you can use the companion JumpToTrailingWhitespace.vim plugin (vimscript #3968).
There are already a number of plugins for this purpose, most based on this VimTip: http://vim.wikia.com/wiki/Highlight_unwanted_spaces However, most of them use the older :match command and are not as flexible.
- smartmatcheol.vim (vimscript #2635) highlights based on file extension or name.
- trailing-whitespace (vimscript #3201) uses :match.
- bad-whitespace (vimscript #3735) uses :match, allows on/off/toggling via commands.
- Trailer Trash (vimscript #3938) uses :match.
- DynamicSigns (vimscript #3965) can show whitespace errors (also mixed indent) in the sign column.
- better-whitespace (vimscript #4859) can use either :match or :syntax (with the option of excluding the current line), and has a :StripWhitespace command, also automatic triggering for some filetypes.
- ShowSpaces (vimscript #5148) highlights spaces inside indentation, per buffer / filetype.
By default, trailing whitespace is highlighted in all Vim buffers. Some users
may want to selectively enable / disable this for certain filetypes, or files
in a particular directory hierarchy, or toggle this on demand. Since it's
difficult to accommodate all these demands with short and easy mappings and
commands, this plugin does not define any of them, and leaves it to you to
tailor the plugin to your needs. See ShowTrailingWhitespace-configuration
below.
The code is hosted in a Git repo at https://github.com/inkarkat/vim-ShowTrailingWhitespace You can use your favorite plugin manager, or "git clone" into a directory used for Vim packages. Releases are on the "stable" branch, the latest unstable development snapshot on "master".
This script is also packaged as a vimball. If you have the "gunzip" decompressor in your PATH, simply edit the *.vmb.gz package in Vim; otherwise, decompress the archive first, e.g. using WinZip. Inside Vim, install by sourcing the vimball or via the :UseVimball command.
vim ShowTrailingWhitespace*.vmb.gz
:so %
To uninstall, use the :RmVimball command.
- Requires Vim 7.1 with "matchadd()", or Vim 7.2 or higher.
- Requires the ingo-library.vim plugin (vimscript #4433), version 1.043 or higher.
For a permanent configuration, put the following commands into your vimrc:
To change the highlighting colors (do this after any :colorscheme):
highlight ShowTrailingWhitespace ctermbg=Red guibg=Red
The default highlighting links to the "Error" highlight group.
As a background color is needed to highlight the whitespace, the plugin inspects the linked highlight group and switches to its foreground color if your chosen colorscheme does not define a background color there. You can turn off this logic via:
let g:ShowTrailingWhitespace_IsAutomaticBackground = 0
By default, highlighting is enabled for all buffers, and you can (selectively) disable it. To work from the opposite premise, launch Vim with highlighting disabled:
let g:ShowTrailingWhitespace = 0
With regards to exceptions, the plugin offers multiple approaches: The most generic is a filter function where your code tells the plugin whether it should check or ignore. By default, the plugin uses this to offer a file-based set of blacklists, one persisted and one only for the current session. Alternatively, you can use Vim's built-in functionality like :autocmd or filetype-plugins, and invoke plugin function to enable / disable it from there. These plugin functions can also be used to define custom toggle commands or mappings, allowing you to interactively control the plugin.
In addition to toggling the highlighting on/off via g:ShowTrailingWhitespace, the decision can also be influenced by buffer settings or the environment. By default, buffers that are not persisted to disk (unless they are explicitly marked as "[Scratch]" buffers) or not modifiable (like user interface windows from various plugins, but note that clearing the option is usually done too late) are skipped. You can disable this filtering:
let g:ShowTrailingWhitespace_FilterFunc = ''
or install your own custom filter function instead:
let g:ShowTrailingWhitespace_FilterFunc = function('MyFunc')
The default filter also checks two blacklists:
- *g:ShowTrailingWhitespace_Blacklist* (valid for the current Vim session)
- *g:SHOWTRAILINGWHITESPACE_BLACKLIST* (persisted across Vim sessions) You can define your own commands or mappings to add or remove the current file to that blacklist:
command! -bar ShowTrailingWhitespaceBlacklistForSession call ShowTrailingWhitespace#Filter#BlacklistFile(0)
command! -bar ShowTrailingWhitespaceBlacklistPermanently call ShowTrailingWhitespace#Filter#BlacklistFile(1)
command! -bar ShowTrailingWhitespaceBlacklistRemoveFile call ShowTrailingWhitespace#Filter#RemoveFileFromBlacklist()
Highlighting can be enabled / disabled globally and for individual buffers. Analog to the :set and :setlocal commands, you can define the following commands:
command! -bar ShowTrailingWhitespaceOn call ShowTrailingWhitespace#Set(1,1)
command! -bar ShowTrailingWhitespaceOff call ShowTrailingWhitespace#Set(0,1)
command! -bar ShowTrailingWhitespaceBufferOn call ShowTrailingWhitespace#Set(1,0)
command! -bar ShowTrailingWhitespaceBufferOff call ShowTrailingWhitespace#Set(0,0)
To set the local highlighting back to its global value (like :set {option}< does), the following command can be defined:
command! -bar ShowTrailingWhitespaceBufferClear call ShowTrailingWhitespace#Reset()
You can also define a quick mapping to toggle the highlighting (here, locally; for global toggling use ShowTrailingWhitespace#Toggle(1):
nnoremap <silent> <Leader>t$ :<C-u>call ShowTrailingWhitespace#Toggle(0)<Bar>
\ echo (ShowTrailingWhitespace#IsSet() ?
\ 'Show trailing whitespace' :
\ 'Not showing trailing whitespace')<CR>
For some filetypes, trailing whitespace is part of the syntax or even mandatory. To disable the plugin for a filetype, put the following in a file named e.g. ftplugin/{filetype}_ShowTrailingWhitespace.vim:
if ShowTrailingWhitespace#IsSet()
call ShowTrailingWhitespace#Set(0,0)
endif
The plugin already ships with some common exceptions; you can submit yours, too!
Some filetypes need trailing whitespace only in certain places. If you don't want to be bothered by these showing up as false positives, you may be able to augment the regular expression so that these places do not match. The ShowTrailingWhitespace#SetLocalExtraPattern() function takes a regular expression that is prepended to the pattern for the trailing whitespace ('\s\+\%#\@<!$' in insert mode, '\s\+$' otherwise). For a certain filetype, this is best set in a file ftplugin/{filetype}_ShowTrailingWhitespace.vim.
The ShowTrailingWhitespace#IsSet() function can be used to query the on/off status for the current buffer, e.g. for use in the statusline.
To obtain the pattern for matching trailing whitespace, including any ShowTrailingWhitespace-exceptions, you can use the function ShowTrailingWhitespace#Pattern(0).
Report any bugs, send patches, or suggest features via the issue tracker at https://github.com/inkarkat/vim-ShowTrailingWhitespace/issues or email (address below).
- More robust and efficient iteration through visible windows through win_execute() (where available).
- Add (hard, previously only optional) dependency to ingo-library (vimscript #4433).
- diff filetype: Exclude patch instructions that just consist of # + single space.
You need to separately install ingo-library (vimscript #4433) version 1.043 (or higher)!
- Neovim does not have the TerminalOpen event; don't use it then, to avoid startup errors. (Patch by subnut.)
- Exempt the "xxd" filetype used e.g. by the Hexman plugin (vimscript #666).
- ENH: The plugin now inspects the linked highlight group and switches to its foreground color if your chosen colorscheme does not define a background color there, to avoid that no trailing whitespace highlighting can be seen. This logic can be disabled through g:ShowTrailingWhitespace_IsAutomaticBackground. Thanks to subnut for raising this issue, providing a suggestion on how to fix that and a patch for Neovim compatibility.
- The default g:ShowTrailingWhitespace_FilterFunc now also skips highlighting in |terminal-window|s. Unfortunately, this requires a special hook, as the 'buftype' gets set too late.
- ENH: Make the default filter also consider session-local and persistent blacklists for files where highlighting should be off. Offer public functions to implement custom commands or mappings for blacklist management. See ShowTrailingWhitespace-blacklist for details.
- FIX: Avoid creating jump when enabling / setting a local extra pattern.
You need to separately install ingo-library (vimscript #4433) version 1.036 (or higher) in order to use the blacklist feature!
- Exempt the "unite" filetype used by the Unite plugin (vimscript #3396). Thanks to Fernando "Firef0x" G.P. da Silva for the patch.
- Add whitespace exception for the "markdown" filetype.
- Make ShowTrailingWhitespace#IsSet() also handle Vim 7.0/1 where the g:ShowTrailingWhitespace variable is not set. Return 0 instead of causing a function abort.
- ENH: Keep previous (last accessed) window on :windo.
- Minor: Also exclude quickfix and help buffers from detection.
- Add whitespace exception for the "dosbatch" filetype.
- First published version.
- Started development.
Copyright: (C) 2012-2022 Ingo Karkat - The VIM LICENSE applies to this plugin.
Maintainer: Ingo Karkat <ingo@karkat.de>