rebrand to u.nvim

lua/u/state.lua

@@ -0,0 +1,90 @@
+---@class State
+---@field buf number
+---@field registers table
+---@field marks table
+---@field positions table
+---@field keymaps { mode: string; lhs: any, rhs: any, buffer?: number }[]
+---@field global_options table<string, any>
+---@field win_view vim.fn.winsaveview.ret|nil
+local State = {}
+
+---@param buf number
+---@return State
+function State.new(buf)
+  if buf == 0 then buf = vim.api.nvim_get_current_buf() end
+  local s = { buf = buf, registers = {}, marks = {}, positions = {}, keymaps = {}, global_options = {} }
+  setmetatable(s, { __index = State })
+  return s
+end
+
+---@generic T
+---@param buf number
+---@param f fun(s: State):T
+---@return T
+function State.run(buf, f)
+  local s = State.new(buf)
+  local ok, result = pcall(f, s)
+  s:restore()
+  if not ok then error(result) end
+  return result
+end
+
+---@param buf number
+---@param f fun(s: State, callback: fun(): any):any
+---@param callback fun():any
+function State.run_async(buf, f, callback)
+  local s = State.new(buf)
+  f(s, function()
+    s:restore()
+    callback()
+  end)
+end
+
+function State:track_keymap(mode, lhs)
+  local old =
+    -- Look up the mapping in buffer-local maps:
+    vim.iter(vim.api.nvim_buf_get_keymap(self.buf, mode)):find(function(map) return map.lhs == lhs end)
+    -- Look up the mapping in global maps:
+    or vim.iter(vim.api.nvim_get_keymap(mode)):find(function(map) return map.lhs == lhs end)
+
+  -- Did we find a mapping?
+  if old == nil then return end
+
+  -- Track it:
+  table.insert(self.keymaps, { mode = mode, lhs = lhs, rhs = old.rhs or old.callback, buffer = old.buffer })
+end
+
+---@param reg string
+function State:track_register(reg) self.registers[reg] = vim.fn.getreg(reg) end
+
+---@param mark string
+function State:track_mark(mark) self.marks[mark] = vim.api.nvim_buf_get_mark(self.buf, mark) end
+
+---@param pos string
+function State:track_pos(pos) self.positions[pos] = vim.fn.getpos(pos) end
+
+---@param nm string
+function State:track_global_option(nm) self.global_options[nm] = vim.g[nm] end
+
+function State:track_winview() self.win_view = vim.fn.winsaveview() end
+
+function State:restore()
+  for reg, val in pairs(self.registers) do
+    vim.fn.setreg(reg, val)
+  end
+  for mark, val in pairs(self.marks) do
+    vim.api.nvim_buf_set_mark(self.buf, mark, val[1], val[2], {})
+  end
+  for pos, val in pairs(self.positions) do
+    vim.fn.setpos(pos, val)
+  end
+  for _, map in ipairs(self.keymaps) do
+    vim.keymap.set(map.mode, map.lhs, map.rhs, { buffer = map.buffer })
+  end
+  for nm, val in pairs(self.global_options) do
+    vim.g[nm] = val
+  end
+  if self.win_view ~= nil then vim.fn.winrestview(self.win_view) end
+end
+
+return State