A neovim function that smartly indents the current line

smart_indent.lua

-- A neovim function that smartly indents the current line
-- By github.com/amekusa
-- Tested with neovim v0.10
-- 
-- # What it does
-- If the current line is empty,
-- copies the indentations of the previous or the next line. (The longer one is chosen)
--
-- If the current line is not empty,
-- simpy shift it to right.
--
function smart_indent()
	local _
	local line = vim.api.nvim_get_current_line()
	if line == '' then -- empty line
		vim.cmd.startinsert()
		local lnum     = vim.api.nvim_win_get_cursor(0)[1]
		local lnum_max = vim.api.nvim_buf_line_count(0)

		-- get indents in the prev line
		local indents_prev = ''
		if lnum > 1 then
			_,_,indents_prev = vim.api.nvim_buf_get_lines(0, lnum - 2, lnum - 1, true)[1]:find([[^(%s*)]])
		end

		-- get indents in the next line
		local indents_next = ''
		if lnum < lnum_max then
			_,_,indents_next = vim.api.nvim_buf_get_lines(0, lnum, lnum + 1, true)[1]:find([[^(%s*)]])
		end

		-- use longer one
		local len_prev = indents_prev:len()
		local len_next = indents_next:len()
		if len_prev > 0 or len_next > 0 then
			if len_prev > len_next
				then vim.api.nvim_set_current_line(indents_prev)
				else vim.api.nvim_set_current_line(indents_next)
			end
			vim.api.nvim_win_set_cursor(0, {lnum, 1000}) -- set cursor to EoL
		else
			vim.api.nvim_feedkeys(fn.key('<Tab>'), 'n', false) -- just type <Tab>
		end
	else
		vim.cmd('>') -- shift the current line to right
	end
end

A neovim function that smartly indents the current line

By github.com/amekusa
Tested with neovim v0.10

What it does

If the current line is empty,
copies the indentations of the previous or the next line. (The longer one is chosen)

If the current line is not empty,
simpy shift it to right.