nvim: Add snippets with luasnip

1 files changed, 202 insertions, 3 deletions

diff --git a/.config/nvim/after/plugin/luasnip.lua b/.config/nvim/after/plugin/luasnip.lua
index 8216615..6d9d662 100644
--- a/.config/nvim/after/plugin/luasnip.lua
+++ b/.config/nvim/after/plugin/luasnip.lua
@@ -1,4 +1,203 @@
-local luasnip = require('luasnip')
+local ls = require('luasnip')
+local ts_utils = require('nvim-treesitter.ts_utils')
+local ts_locals = require('nvim-treesitter.locals')
 
-vim.keymap.set('i', '<C-l>', function() luasnip.jump(1) end)
-vim.keymap.set('i', '<C-h>', function() luasnip.jump(-1) end)
+local c = ls.choice_node
+local d = ls.dynamic_node
+local f = ls.function_node
+local i = ls.insert_node
+local s = ls.s
+local sn = ls.snippet_node
+local t = ls.text_node
+local fmt = require('luasnip.extras.fmt').fmt
+
+ls.config.set_config {
+	history = true,
+	updateevents = 'TextChanged,TextChangedI',
+}
+
+ls.add_snippets('lua', {
+	s('req', fmt([[local {} = require('{}')]], {
+		f(function(name)
+			local xs = vim.split(name[1][1], '.', { plain = true })
+			return xs[#xs] or ''
+		end, { 1 }),
+		i(1),
+	})),
+})
+
+local function is_ptr(str)
+	return string.find(str, '*', 1, true) ~= nil
+end
+
+local function is_num(str)
+	return vim.regex(
+		'\\v^('
+		.. 'u?int(8|16|32|64)?'
+		.. '|byte'
+		.. '|complex(64|128)'
+		.. '|float(32|64)'
+		.. '|rune'
+		.. '|uintptr'
+		.. ')$'
+	):match_str(str) ~= nil
+end
+
+local transforms = {
+	bool = 'false',
+	string = '""',
+	error = 'err',
+	[is_num] = '0',
+	[is_ptr] = 'nil',
+}
+
+local transform = function(text)
+	local condition_matches = function(condition, ...)
+		if type(condition) == 'string' then
+			return condition == text
+		else
+			return condition(...)
+		end
+	end
+
+	for condition, result in pairs(transforms) do
+		if condition_matches(condition, text) then
+			return t(result)
+		end
+	end
+
+	return t(text .. '{}')
+end
+
+local handlers = {
+	parameter_list = function(node)
+		local result = {}
+
+		local count = node:named_child_count()
+		for idx = 0, count - 1 do
+			local matching_node = node:named_child(idx)
+			local type_node = matching_node:field('type')[1]
+			table.insert(result, transform(
+				vim.treesitter.get_node_text(type_node, 0)
+			))
+			if idx ~= count - 1 then
+				table.insert(result, t({ ', ' }))
+			end
+		end
+
+		return result
+	end,
+
+	type_identifier = function(node)
+		local text = vim.treesitter.get_node_text(node, 0)
+		return { transform(text) }
+	end,
+}
+
+local function_node_types = {
+	function_declaration = true,
+	method_declaration = true,
+	func_literal = true,
+}
+
+local function go_result_type()
+	local cursor_node = ts_utils.get_node_at_cursor()
+	if cursor_node == nil then
+		print('Unable to find position')
+		return t('')
+	end
+	local scope = ts_locals.get_scope_tree(cursor_node, 0)
+
+	local function_node
+	for _, v in ipairs(scope) do
+		if function_node_types[v:type()] then
+			function_node = v
+			break
+		end
+	end
+
+	if not function_node then
+		print('Not inside of a function')
+		return t('')
+	end
+
+	local query = vim.treesitter.query.parse('go', [[
+		[
+			(method_declaration result: (_) @id)
+			(function_declaration result: (_) @id)
+			(func_literal result: (_) @id)
+		]
+	]])
+	for _, node in query:iter_captures(function_node, 0) do
+		if handlers[node:type()] then
+			return handlers[node:type()](node)
+		end
+	end
+end
+
+ls.add_snippets('go', {
+	s(
+		'f',
+		fmt(
+			[[
+				func <><>() <>{
+					<>
+				}
+			]],
+			{
+				c(1, {
+					t(''),
+					t('() '),
+				}),
+				i(2, 'name'),
+				c(3, {
+					t(''),
+					t('() '),
+				}),
+				i(0),
+			},
+			{
+				delimiters = '<>',
+			}
+		)
+	),
+	s(
+		'ife',
+		fmt(
+			[[
+				if err != nil {
+					return <>
+				}
+			]],
+			{
+				d(1, function()
+					return sn(nil, go_result_type())
+				end),
+			},
+			{
+				delimiters = '<>',
+			}
+		)
+	),
+})
+
+vim.keymap.set({ 'i', 's' }, '<C-l>', function()
+	if ls.expand_or_jumpable() then
+		ls.expand_or_jump()
+	end
+end)
+vim.keymap.set('i', '<C-h>', function()
+	if ls.jumpable(-1) then
+		ls.jump(-1)
+	end
+end)
+vim.keymap.set('i', '<C-k>', function()
+	if ls.choice_active() then
+		ls.change_choice(-1)
+	end
+end)
+vim.keymap.set('i', '<C-j>', function()
+	if ls.choice_active() then
+		ls.change_choice(1)
+	end
+end)