dressing.nvim/README.md

# Dressing.nvim

With the release of Neovim 0.6 we were given the start of extensible core UI
hooks ([vim.ui.select](https://github.com/neovim/neovim/pull/15771) and
[vim.ui.input](https://github.com/neovim/neovim/pull/15959)). They exist to
allow plugin authors to override them with improvements upon the default
behavior, so that's exactly what we're going to do.

It is a goal to match and not extend the core Neovim API. All options that core
respects will be respected, and we will not accept any custom parameters or
options in the functions. Customization will be done entirely using a separate
[configuration](#configuration) method.

- [Requirements](#requirements)
- [Screenshots](#screenshots)
- [Installation](#installation)
- [Configuration](#configuration)
- [Advanced configuration](#advanced-configuration)
- [Notes for plugin authors](#notes-for-plugin-authors)
- [Alternative and related projects](#alternative-and-related-projects)

## Requirements

Neovim 0.5+

On versions prior to 0.6, this plugin will act as a polyfill for `vim.ui`

## Screenshots

`vim.input` replacement (handling a LSP rename)

![Screenshot from 2021-12-09 17-36-16](https://user-images.githubusercontent.com/506791/145502533-3dc2f87d-95ea-422d-a318-12c0092f1bdf.png)

`vim.select` (telescope)

![Screenshot from 2021-12-02 19-46-01](https://user-images.githubusercontent.com/506791/144541916-4fa60c50-cadc-4f0f-b3c1-6307310e6e99.png)

`vim.select` (fzf)

![Screenshot from 2021-12-02 19-46-54](https://user-images.githubusercontent.com/506791/144541986-6081b4f8-b3b2-418d-9265-b9dabec2c4c4.png)

`vim.select` (nui)

![Screenshot from 2021-12-02 19-47-56](https://user-images.githubusercontent.com/506791/144542071-1aa66f81-b07c-492e-9884-fdafed1006df.png)

`vim.select` (built-in)

![Screenshot from 2021-12-04 17-14-32](https://user-images.githubusercontent.com/506791/144729527-ede0d7ba-a6e6-41e0-be5a-1a5f16d35b05.png)

## Installation

dressing.nvim supports all the usual plugin managers

<details>
  <summary>Packer</summary>

```lua
require('packer').startup(function()
    use {'stevearc/dressing.nvim'}
end)
```

</details>

<details>
  <summary>Paq</summary>

```lua
require "paq" {
    {'stevearc/dressing.nvim'};
}
```

</details>

<details>
  <summary>vim-plug</summary>

```vim
Plug 'stevearc/dressing.nvim'
```

</details>

<details>
  <summary>dein</summary>

```vim
call dein#add('stevearc/dressing.nvim')
```

</details>

<details>
  <summary>Pathogen</summary>

```sh
git clone --depth=1 https://github.com/stevearc/dressing.nvim.git ~/.vim/bundle/
```

</details>

<details>
  <summary>Neovim native package</summary>

```sh
git clone --depth=1 https://github.com/stevearc/dressing.nvim.git \
  "${XDG_DATA_HOME:-$HOME/.local/share}"/nvim/site/pack/dressing.nvim/start/dressing.nvim
```

</details>

## Configuration

If you're fine with the defaults, you're good to go after installation. If you
want to tweak, call this function:

```lua
require('dressing').setup({
  input = {
    -- Set to false to disable the vim.ui.input implementation
    enabled = true,

    -- Default prompt string
    default_prompt = "Input:",

    -- Can be 'left', 'right', or 'center'
    prompt_align = "left",

    -- When true, <Esc> will close the modal
    insert_only = true,

    -- These are passed to nvim_open_win
    anchor = "SW",
    border = "rounded",
    -- 'editor' and 'win' will default to being centered
    relative = "cursor",

    -- These can be integers or a float between 0 and 1 (e.g. 0.4 for 40%)
    prefer_width = 40,
    width = nil,
    -- min_width and max_width can be a list of mixed types.
    -- min_width = {20, 0.2} means "the greater of 20 columns or 20% of total"
    max_width = { 140, 0.9 },
    min_width = { 20, 0.2 },

    -- Window transparency (0-100)
    winblend = 10,
    -- Change default highlight groups (see :help winhl)
    winhighlight = "",

    override = function(conf)
      -- This is the config that will be passed to nvim_open_win.
      -- Change values here to customize the layout
      return conf
    end,

    -- see :help dressing_get_config
    get_config = nil,
  },
  select = {
    -- Set to false to disable the vim.ui.select implementation
    enabled = true,

    -- Priority list of preferred vim.select implementations
    backend = { "telescope", "fzf_lua", "fzf", "builtin", "nui" },

    -- Options for telescope selector
    -- These are passed into the telescope picker directly. Can be used like:
    -- telescope = require('telescope.themes').get_ivy({...})
    telescope = nil,

    -- Options for fzf selector
    fzf = {
      window = {
        width = 0.5,
        height = 0.4,
      },
    },

    -- Options for fzf_lua selector
    fzf_lua = {
      winopts = {
        width = 0.5,
        height = 0.4,
      },
    },

    -- Options for nui Menu
    nui = {
      position = "50%",
      size = nil,
      relative = "editor",
      border = {
        style = "rounded",
      },
      max_width = 80,
      max_height = 40,
    },

    -- Options for built-in selector
    builtin = {
      -- These are passed to nvim_open_win
      anchor = "NW",
      border = "rounded",
      -- 'editor' and 'win' will default to being centered
      relative = "editor",

      -- Window transparency (0-100)
      winblend = 10,
      -- Change default highlight groups (see :help winhl)
      winhighlight = "",

      -- These can be integers or a float between 0 and 1 (e.g. 0.4 for 40%)
      -- the min_ and max_ options can be a list of mixed types.
      -- max_width = {140, 0.8} means "the lesser of 140 columns or 80% of total"
      width = nil,
      max_width = { 140, 0.8 },
      min_width = { 40, 0.2 },
      height = nil,
      max_height = 0.9,
      min_height = { 10, 0.2 },

      override = function(conf)
        -- This is the config that will be passed to nvim_open_win.
        -- Change values here to customize the layout
        return conf
      end,
    },

    -- Used to override format_item. See :help dressing-format
    format_item_override = {},

    -- see :help dressing_get_config
    get_config = nil,
  },
})
```

## Advanced configuration

For each of the `input` and `select` configs, there is an option
`get_config`. This can be a function that accepts the `opts` parameter that
is passed in to `vim.select` or `vim.input`. It must return either `nil` (to
no-op) or config values to use in place of the global config values for that
module.

For example, if you want to use a specific configuration for code actions:

```lua
require('dressing').setup({
  select = {
    get_config = function(opts)
      if opts.kind == 'codeaction' then
        return {
          backend = 'nui',
          nui = {
            relative = 'cursor',
            max_width = 40,
          }
        }
      end
    end
  }
})

```

## Notes for plugin authors

TL;DR: you can customize the telescope `vim.ui.select` implementation by passing `telescope` into `opts`.

The `vim.ui` hooks are a great boon for us because we can now assume that users
will have a reasonable UI available for simple input operations. We no longer
have to build separate implementations for each of fzf, telescope, ctrlp, etc.
The tradeoff is that `vim.ui.select` is less customizable than any of these
options, so if you wanted to have a preview window (like telescope supports), it
is no longer an option.

My solution to this is extending the `opts` that are passed to `vim.ui.select`.
You can add a `telescope` field that will be passed directly into the picker,
allowing you to customize any part of the UI. If a user has both dressing and
telescope installed, they will get your custom picker UI. If either of those
are not true, the selection UI will gracefully degrade to whatever the user has
configured for `vim.ui.select`.

An example of usage:

```lua
vim.ui.select({'apple', 'banana', 'mango'}, {
  prompt = "Title",
  telescope = require("telescope.themes").get_cursor(),
}, function(selected) end)
```

For now this is available only for the telescope backend, but feel free to request additions.

## Alternative and related projects

- [telescope-ui-select](https://github.com/nvim-telescope/telescope-ui-select.nvim) - provides a `vim.ui.select` implementation for telescope
- [nvim-fzy](https://github.com/mfussenegger/nvim-fzy) - fzf alternative that also provides a `vim.ui.select` implementation ([#13](https://github.com/mfussenegger/nvim-fzy/pull/13))
- [guihua.lua](https://github.com/ray-x/guihua.lua) - multipurpose GUI library that provides `vim.ui.select` and `vim.ui.input` implementations
- [nvim-notify](https://github.com/rcarriga/nvim-notify) - doing pretty much the
  same thing but for `vim.notify`
- [nui.nvim](https://github.com/MunifTanjim/nui.nvim) - provides common UI
  components for plugin authors