Vertical window splits by default, with exceptions

The below pairing of autocommands sets Neovim to open all new window splits as vertical splits. Two autocommands are needed as there are some windows which are nicer to have as their intended / original horizontal splits, such as the quick fix list.

-- Open all new windows as vertical splits
auto({ "WinNew" }, {
	group = "windows",
	pattern = "*", -- apply to all
	callback = function()
		vim.cmd("wincmd L")
	end,
})

wincmd L is the same as <C-w> L. See :help wincmd. It sets the new window to be a vertical split on the left side. If you’d prefer to open your new windows to the right, set vim.cmd("wincmd R").

The WinNew event executes as the window is created, but (and I could be wrong here) at this point we can’t retrieve the file type of the buffer within that window. However, after the new window is created, the cursor jumps to it. The BufEnter event is therefore triggered, which means that we can query the file type of the buffer and act upon it.

So, if the file type is qf (quick fix list) or trouble (trouble.nvim 🙌), the split will be set to horizontal.

-- If the entered buffer is one of horizontal_ftypes, move to bottom
-- horizontal window.
local horizontal_ftypes = { "qf", "trouble" }
auto({ "BufEnter" }, {
	group = "windows",
	callback = function()
		local ft = vim.bo.filetype
		if vim.tbl_contains(horizontal_ftypes, ft) then
			vim.cmd("wincmd J")
		end
	end,
})

As mentioned, in the case of the quick fix list and trouble, both open as horizontal splits by default. Despite them being effectively moved from a horizontal split, to a vertical and then back to horizontal again, the changes appear ‘instantaneous’. So, based on that, this solution feels acceptable for me at least.

But if anyone has an solution to achieve the file type query logic within the WinNew event, shoot me an email!