feature: allow pick_win to ignore specific filetypes and buftypes

[jemag]

Did you check the docs?

• I have read all the snacks.nvim docs

Is your feature request related to a problem? Please describe.

snacks.picker.util.pick_win is extremely useful to my workflow. I use it countless times each day alongside other plugins.

The only remaining problem that I miss from nvim-window-picker is the possibility to ignore specific filetype and buftype.For example, I use snacks.picker.util.pick_win with neo-tree to pick and split pick windows to edit from. However, currently neo-tree itself will appear in the list of possible windows, as it cannot be excluded.
Here is an example workflow with pick_win

https://github.com/user-attachments/assets/a29a4798-2eba-4a24-9769-b356307c38c5
Here is the current equivalent with nvim-window-picker
https://github.com/user-attachments/assets/713aa272-4635-4a6a-a061-1d6f5ee42491

Currently, with nvim-window-picker the first split is instant given only 1 window is detected, and subsequent splits do not give neo-tree as a choice

Describe the solution you'd like

Provide configurable filetype and buftype exclusions, e.g.:

      filetype = { "notify", "neo-tree", "neo-tree-popup", "quickfix", "scrollview", "snacks_picker_preview"},

      -- if the buffer type is one of following, the window will be ignored
      buftype = {"nofile", "prompt"},

Describe alternatives you've considered

Not transition these specific workflows to snacks pick_win

Additional context

I think it would be really nice to publicize pick_win as a full fledged snacks rather than a utility function.

Although simple it is incredibly powerful for numerous workflows. For example:
Simple selection + splitting with snacks.picker:

          ["<c-v>"] = { { "pick_win", "edit_vsplit" }, mode = { "i", "n" } },
          ["<c-s>"] = { { "pick_win", "edit_split" }, mode = { "i", "n" } },
          ["<c-e>"] = { { "pick_win", "edit" }, mode = { "i", "n" } },

Moving, swapping, close windows with pick_win

local function switch_window()
  local window = snacks.picker.util.pick_win()
  if window ~= nil then
    vim.api.nvim_set_current_win(window)
  end
end
local function close_window()
  local window = snacks.picker.util.pick_win()
  if window ~= nil then
    vim.api.nvim_win_close(window, false)
  end
end
local function swap_window()
  local picked_window = snacks.picker.util.pick_win()
  if picked_window ~= nil then
    local picked_buffer = vim.api.nvim_win_get_buf(picked_window)
    local current_buffer = vim.api.nvim_get_current_buf()
    local current_window = vim.api.nvim_get_current_win()
    vim.api.nvim_win_set_buf(picked_window, current_buffer)
    vim.api.nvim_win_set_buf(current_window, picked_buffer)
  end
end

vim.keymap.set("n", "<c-w>S", swap_window, { desc = "Swap window by id" })
vim.keymap.set("n", "<c-w>m", switch_window, { desc = "Move to window by id" })
vim.keymap.set("n", "<c-w>Q", close_window, { desc = "Close window by id" })

Splitting with neo-tree and pick_win

    commands = {
      pick = function(state)
        local path = state.tree:get_node().path
        local win = require("snacks").picker.util.pick_win()
        if win ~= nil then
          vim.api.nvim_set_current_win(win)
          vim.cmd("edit " .. path)
        end
      end,
      pick_split = function(state)
        local path = state.tree:get_node().path
        local win = require("snacks").picker.util.pick_win()
        if win ~= nil then
          vim.api.nvim_set_current_win(win)
          vim.cmd("split " .. path)
        end
      end,
      pick_vsplit = function(state)
        local path = state.tree:get_node().path
        local win = require("snacks").picker.util.pick_win()
        if win ~= nil then
          vim.api.nvim_set_current_win(win)
          vim.cmd("vsplit " .. path)
        end
      end,   
    },

[folke]

I'm going to turn this in a separate module at some point.

For now, I just added some extra options:

---@param opts? {main?: number, float?:boolean, filter?: fun(win:number, buf:number):boolean?}
function M.pick_win(opts)

[jemag]

amazing thanks!

Whenever it does become a module, I think it could be nice to be able to configure the filter function globally (with possibility of local override when calling pick_win)

That way, no need to pass it on every pick_win call, and also it would still be possible to use the snacks.picker pick_win action with the default filtering applying.
For now, instead of the pick_win action, I am doing the following to filter out neo-tree and other buffers with snacks.picker:

    actions = {
      pick_vsplit = function(picker, item)
        picker:close()
        local win = snacks.picker.util.pick_win({ filter = filter_windows })
        if win ~= nil then
          vim.api.nvim_set_current_win(win)
          picker:action("edit_vsplit")
        end
      end,

[folke]

you can also just overide the pick_win action in your config to have it applied for all pickers.
But yes indeed a global filter is the better option when I get to it.