# vis-editorconfig

A [vis][vis] plugin for [editorconfig][ec].

[vis]: https://github.com/martanne/vis
[ec]: http://editorconfig.org/

## Installation

You'll need the Lua wrapper for editorconfig-core installed. This can
be done through luarocks: `luarocks install editorconfig-core`

```shell
git clone https://github.com/seifferth/vis-editorconfig "$HOME/.config/vis/edconf"
```

Then add `require('edconf')` to your `visrc.lua`.

You may use a different name for the local repository, if you like.
You could, for instance, use `$HOME/.config/vis/vis-editorconfig` and
`require('vis-editorconfig')`.  Note, however, that the repository **must
not** be called `editorconfig`.  Since the editorconfig-core lua library
is also called `editorconfig`, naming the repository `editorconfig`
will cause name conflicts that result in infinite recursion.

## Functionality

Not all editorconfig functionality is supported by vis and hence by this
plugin. At this moment, there is full support for the following settings:

- indent_style
- indent_size
- tab_width
- insert_final_newline

The following settings are implemented partially and / or support is
turned off by default:

- spell_language: This is not yet part of the editorconfig specification
  (cf. <https://github.com/editorconfig/editorconfig/issues/315>), but
  it is implemented anyway. Since vis does not support spellchecking
  natively, this plugin will only set `vis.win.file.spell_language` to
  the specified value. It is then up to the spellchecking plugin to
  respect that variable.
- trim_trailing_whitespace: Turned off by default, can be enabled
  via `:set edconfhooks on`.
- end_of_line: Turned off by default, partial support can be enabled
  via `:set edconfhooks on`. Only `crlf` and `lf` are supported, plain
  `cr` is not. The implementation is also very basic. If end_of_line
  is set to `crlf`, a return character will be inserted at the end of
  each line that does not yet end with `crlf`. If end_of_line is set
  to `lf`, return characters at the end of a line will be stripped.
  While I would encourage every vis user to stick to `lf` terminated
  files, this might be convenient if, for some reason, they do need
  to compose `crlf` terminated files.
- max_line_length: Turned off by default, partial support can be
  enabled via `:set edconfhooks on`. There is no straightforward way
  to automatically wrap content that might be written in arbitrary
  programming (or non-programming) languages. For that reason,
  vis-editorconfig doesn't even try. If max_line_length is enabled,
  vis-editorconfig issues a warning, however, indicating which lines
  are longer than the specified length. Note that you will miss this
  warning if you write your file with `:wq`, so if you care about it,
  write it with `:w<RETURN>:q`.

The reason those last three settings are optional and turned off by
default is their scalability. Each of those operations is implemented
as a pre-save-hook with a complexity of O(n), where n is the filesize.
Since vis is incredibly good at editing huge files efficiently, there
seems to be a very real danger that those hooks could cause the editor
to freeze just before a user's valuable changes are written to disk.

You can turn support for those pre-save-hooks on or off at any time
by running

    :set edconfhooks on

or

    :set edconfhooks off

If `edconfhooks` are enabled, they will be executed as configured in
`.editorconfig`. If you want to take a less cautious approach and enable
these hooks by default, simply add an additional line below the module
import in `visrc.lua`:

    require('editorconfig/edconf')
    vis:command('set edconfhooks on')   -- supposing you did previously
                                        -- require('vis')