lengthmatters.vim

Highlight the part of a line that doesn't fit into textwidth (or really, whatever width you like).

I've had this functionality in my .vimrc for a long time, and finally decided to extract it into a plugin. The idea is extremely simple, a gazillion examples of how to to this can be found online, but still... I like making plugins.

Maintenance

I had stopped maintaining this project but the superkind Francisco (@oblitum) stepped up and offered to take over maintenance, so he's the maintainer now. Thanks Francisco! 💟

Installation

I personally moved from Vundle to vim-plug a while ago and never looked back. Anyways, whatever floats your boat:

" vim-plug
Plug 'whatyouhide/vim-lengthmatters'
" NeoBundle
NeoBundle 'whatyouhide/vim-lengthmatters'
" Vundle
Plugin 'whatyouhide/vim-lengthmatters'

You pathogen dinosaurs can just clone the repo:

git clone https://github.com/whatyouhide/vim-lengthmatters.git ~/.vim/bundle

What's in it

The highlighting functionality operates always on a per-window basis, meaning you can keep it enabled on a window and disabled on another one at the same time.

By default, it's based on the value of the textwidth option (it feels right), but this can be changed in the options. See :h 'textwidth' for more infos.

The plugin provides a bunch of commands:

• :LengthmattersToggle: toggle the highlighting for the current window
• :LengthmattersEnable: enable the highlighting for the current window
• :LengthmattersDisable: disable the highlighting for the current window
• :LengthmattersReload: force reloading (useful if something goes wrong, or textwidth changes, or god knows what)
• :LengthmattersEnableAll: enable the highlighting for all open windows
• :LengthmattersDisableAll: disable the highlighting for all open windows

Configuration

To set a variable in vim (for example g:foo to the string foo), just do:

let g:foo = 'foo'

Most of the configuration for this plugin can be done through a handful of variables. The only thing you have to use functions for is highlighting. Read the relative section for how to do it.

g:lengthmatters_on_by_default

(defaults to !&diff)
If this variable is set to 0, no highlighting will be done when opening a new window. Highlighting can still be activated with one of the previously mentioned commands.

g:lengthmatters_start_at_column

(defaults to 81)
The value of this variable is the first character to be highlighted; the highlighting will continue until the end of the line. This means that if it's okay for lines to be 40 characters long (because you're from 1920 or something) you set this variable to 41.

g:lengthmatters_use_textwidth

(defaults to 1)
Whether to highlight based on the value of textwidth. If textwidth is not set, it will fall back to g:lengthmatters_start_at_column.

g:lengthmatters_excluded

(defaults to ['unite', 'tagbar', 'startify', 'gundo', 'vimshell', 'w3m', 'nerdtree', 'help', 'qf', 'dirvish'])

A list of filetypes for which the highlighting isn't (and can't be) enabled. They're regular expressions, so, for example, to disable highlighting in any helper debug window of vim-go, one can add 'godebug.*' to the list.

g:lengthmatters_exclude_readonly

(defaults to 1)
If this variable is set to 1, no highlighting will be done when opening a read-only file.

g:lengthmatters_match_name

(defaults to 'OverLength')
The name of the syntax element that will be used to highlight and match the overly long lines.

g:lengthmatters_highlight_one_column

(defaults to 0)
Only highlight one column instead of all columns up to EOL.

Highlighting

The plugin provides a default highlighting which is based on the current colorscheme. The foreground color is taken from the background color of the Normal highlight group, while the background color is taken from the foreground color of the Comment group. This should look decent on pretty much every colorscheme.

If you want to change that, you have two options.

lengthmatters#highlight

To change the actual colors, use the lengthmatters#highlight function:

call lengthmatters#highlight('ctermbg=3 ctermfg=10')

lengthmatters#highlight_link_to

To link the group to another highlight group, use the lengthmatters#highlight_link_to function:

call lengthmatters#highlight_link_to('ColorColumn')

Note that you have to use one of these two functions in order to manipulate the highlighting, since the plugin performs some dark magic behind the scenes in order to keep the highlighting (and you) happy.

The highlighting is reloaded when you call one of the functions, just as if you called :LengthmattersReload.

Adapt line length for different file types

Different line length in different file types can be achieved with the textwidth variable. For example, if the default line is 80 characters and we want to have a line length of 120 characters only in Java files, we can do it like this:

autocmd bufreadpre *.java setlocal textwidth=120

Testing

If you want to test this plugin, be sure you have vader.vim installed, then open tests/lengthmatters.vader and run :Vader.

License

© Andrea Leopardi