refactor: rename _meta.lua to _options.lua

1 files changed, 575 insertions, 0 deletions

diff --git a/runtime/lua/vim/_options.lua b/runtime/lua/vim/_options.lua
new file mode 100644
index 0000000000..41e6e8be86
--- /dev/null
+++ b/runtime/lua/vim/_options.lua
@@ -0,0 +1,575 @@
+local api = vim.api
+
+-- TODO(tjdevries): Improve option metadata so that this doesn't have to be hardcoded.
+--                  Can be done in a separate PR.
+local key_value_options = {
+  fillchars = true,
+  fcs = true,
+  listchars = true,
+  lcs = true,
+  winhighlight = true,
+  winhl = true,
+}
+
+--- Convert a vimoption_T style dictionary to the correct OptionType associated with it.
+---@return string
+local function get_option_metatype(name, info)
+  if info.type == 'string' then
+    if info.flaglist then
+      return 'set'
+    elseif info.commalist then
+      if key_value_options[name] then
+        return 'map'
+      end
+      return 'array'
+    end
+    return 'string'
+  end
+  return info.type
+end
+
+local options_info = setmetatable({}, {
+  __index = function(t, k)
+    local info = api.nvim_get_option_info(k)
+    info.metatype = get_option_metatype(k, info)
+    rawset(t, k, info)
+    return rawget(t, k)
+  end,
+})
+
+vim.env = setmetatable({}, {
+  __index = function(_, k)
+    local v = vim.fn.getenv(k)
+    if v == vim.NIL then
+      return nil
+    end
+    return v
+  end,
+
+  __newindex = function(_, k, v)
+    vim.fn.setenv(k, v)
+  end,
+})
+
+local function opt_validate(option_name, target_scope)
+  local scope = options_info[option_name].scope
+  if scope ~= target_scope then
+    local scope_to_string = { buf = 'buffer', win = 'window' }
+    error(
+      string.format(
+        [['%s' is a %s option, not a %s option. See ":help %s"]],
+        option_name,
+        scope_to_string[scope] or scope,
+        scope_to_string[target_scope] or target_scope,
+        option_name
+      )
+    )
+  end
+end
+
+local function new_buf_opt_accessor(bufnr)
+  return setmetatable({}, {
+    __index = function(_, k)
+      if bufnr == nil and type(k) == 'number' then
+        return new_buf_opt_accessor(k)
+      end
+      opt_validate(k, 'buf')
+      return api.nvim_get_option_value(k, { buf = bufnr or 0 })
+    end,
+
+    __newindex = function(_, k, v)
+      opt_validate(k, 'buf')
+      return api.nvim_set_option_value(k, v, { buf = bufnr or 0 })
+    end,
+  })
+end
+
+vim.bo = new_buf_opt_accessor()
+
+local function new_win_opt_accessor(winid, bufnr)
+  return setmetatable({}, {
+    __index = function(_, k)
+      if bufnr == nil and type(k) == 'number' then
+        if winid == nil then
+          return new_win_opt_accessor(k)
+        else
+          return new_win_opt_accessor(winid, k)
+        end
+      end
+
+      if bufnr ~= nil and bufnr ~= 0 then
+        error('only bufnr=0 is supported')
+      end
+
+      opt_validate(k, 'win')
+      -- TODO(lewis6991): allow passing both buf and win to nvim_get_option_value
+      return api.nvim_get_option_value(k, {
+        scope = bufnr and 'local' or nil,
+        win = winid or 0,
+      })
+    end,
+
+    __newindex = function(_, k, v)
+      opt_validate(k, 'win')
+      -- TODO(lewis6991): allow passing both buf and win to nvim_set_option_value
+      return api.nvim_set_option_value(k, v, {
+        scope = bufnr and 'local' or nil,
+        win = winid or 0,
+      })
+    end,
+  })
+end
+
+vim.wo = new_win_opt_accessor()
+
+-- vim global option
+--  this ONLY sets the global option. like `setglobal`
+vim.go = setmetatable({}, {
+  __index = function(_, k)
+    return api.nvim_get_option_value(k, { scope = 'global' })
+  end,
+  __newindex = function(_, k, v)
+    return api.nvim_set_option_value(k, v, { scope = 'global' })
+  end,
+})
+
+-- vim `set` style options.
+--  it has no additional metamethod magic.
+vim.o = setmetatable({}, {
+  __index = function(_, k)
+    return api.nvim_get_option_value(k, {})
+  end,
+  __newindex = function(_, k, v)
+    return api.nvim_set_option_value(k, v, {})
+  end,
+})
+
+---@brief [[
+--- vim.opt, vim.opt_local and vim.opt_global implementation
+---
+--- To be used as helpers for working with options within neovim.
+--- For information on how to use, see :help vim.opt
+---
+---@brief ]]
+
+--- Preserves the order and does not mutate the original list
+local function remove_duplicate_values(t)
+  local result, seen = {}, {}
+  for _, v in ipairs(t) do
+    if not seen[v] then
+      table.insert(result, v)
+    end
+
+    seen[v] = true
+  end
+
+  return result
+end
+
+-- Check whether the OptionTypes is allowed for vim.opt
+-- If it does not match, throw an error which indicates which option causes the error.
+local function assert_valid_value(name, value, types)
+  local type_of_value = type(value)
+  for _, valid_type in ipairs(types) do
+    if valid_type == type_of_value then
+      return
+    end
+  end
+
+  error(
+    string.format(
+      "Invalid option type '%s' for '%s', should be %s",
+      type_of_value,
+      name,
+      table.concat(types, ' or ')
+    )
+  )
+end
+
+local function passthrough(_, x)
+  return x
+end
+
+local function tbl_merge(left, right)
+  return vim.tbl_extend('force', left, right)
+end
+
+local function tbl_remove(t, value)
+  if type(value) == 'string' then
+    t[value] = nil
+  else
+    for _, v in ipairs(value) do
+      t[v] = nil
+    end
+  end
+
+  return t
+end
+
+local valid_types = {
+  boolean = { 'boolean' },
+  number = { 'number' },
+  string = { 'string' },
+  set = { 'string', 'table' },
+  array = { 'string', 'table' },
+  map = { 'string', 'table' },
+}
+
+-- Map of functions to take a Lua style value and convert to vimoption_T style value.
+-- Each function takes (info, lua_value) -> vim_value
+local to_vim_value = {
+  boolean = passthrough,
+  number = passthrough,
+  string = passthrough,
+
+  set = function(info, value)
+    if type(value) == 'string' then
+      return value
+    end
+
+    if info.flaglist and info.commalist then
+      local keys = {}
+      for k, v in pairs(value) do
+        if v then
+          table.insert(keys, k)
+        end
+      end
+
+      table.sort(keys)
+      return table.concat(keys, ',')
+    else
+      local result = ''
+      for k, v in pairs(value) do
+        if v then
+          result = result .. k
+        end
+      end
+
+      return result
+    end
+  end,
+
+  array = function(info, value)
+    if type(value) == 'string' then
+      return value
+    end
+    if not info.allows_duplicates then
+      value = remove_duplicate_values(value)
+    end
+    return table.concat(value, ',')
+  end,
+
+  map = function(_, value)
+    if type(value) == 'string' then
+      return value
+    end
+
+    local result = {}
+    for opt_key, opt_value in pairs(value) do
+      table.insert(result, string.format('%s:%s', opt_key, opt_value))
+    end
+
+    table.sort(result)
+    return table.concat(result, ',')
+  end,
+}
+
+--- Convert a Lua value to a vimoption_T value
+local function convert_value_to_vim(name, info, value)
+  if value == nil then
+    return vim.NIL
+  end
+
+  assert_valid_value(name, value, valid_types[info.metatype])
+
+  return to_vim_value[info.metatype](info, value)
+end
+
+-- Map of OptionType to functions that take vimoption_T values and convert to Lua values.
+-- Each function takes (info, vim_value) -> lua_value
+local to_lua_value = {
+  boolean = passthrough,
+  number = passthrough,
+  string = passthrough,
+
+  array = function(info, value)
+    if type(value) == 'table' then
+      if not info.allows_duplicates then
+        value = remove_duplicate_values(value)
+      end
+
+      return value
+    end
+
+    -- Empty strings mean that there is nothing there,
+    -- so empty table should be returned.
+    if value == '' then
+      return {}
+    end
+
+    -- Handles unescaped commas in a list.
+    if string.find(value, ',,,') then
+      local left, right = unpack(vim.split(value, ',,,'))
+
+      local result = {}
+      vim.list_extend(result, vim.split(left, ','))
+      table.insert(result, ',')
+      vim.list_extend(result, vim.split(right, ','))
+
+      table.sort(result)
+
+      return result
+    end
+
+    if string.find(value, ',^,,', 1, true) then
+      local left, right = unpack(vim.split(value, ',^,,', true))
+
+      local result = {}
+      vim.list_extend(result, vim.split(left, ','))
+      table.insert(result, '^,')
+      vim.list_extend(result, vim.split(right, ','))
+
+      table.sort(result)
+
+      return result
+    end
+
+    return vim.split(value, ',')
+  end,
+
+  set = function(info, value)
+    if type(value) == 'table' then
+      return value
+    end
+
+    -- Empty strings mean that there is nothing there,
+    -- so empty table should be returned.
+    if value == '' then
+      return {}
+    end
+
+    assert(info.flaglist, 'That is the only one I know how to handle')
+
+    if info.flaglist and info.commalist then
+      local split_value = vim.split(value, ',')
+      local result = {}
+      for _, v in ipairs(split_value) do
+        result[v] = true
+      end
+
+      return result
+    else
+      local result = {}
+      for i = 1, #value do
+        result[value:sub(i, i)] = true
+      end
+
+      return result
+    end
+  end,
+
+  map = function(info, raw_value)
+    if type(raw_value) == 'table' then
+      return raw_value
+    end
+
+    assert(info.commalist, 'Only commas are supported currently')
+
+    local result = {}
+
+    local comma_split = vim.split(raw_value, ',')
+    for _, key_value_str in ipairs(comma_split) do
+      local key, value = unpack(vim.split(key_value_str, ':'))
+      key = vim.trim(key)
+
+      result[key] = value
+    end
+
+    return result
+  end,
+}
+
+--- Converts a vimoption_T style value to a Lua value
+local function convert_value_to_lua(info, option_value)
+  return to_lua_value[info.metatype](info, option_value)
+end
+
+local prepend_methods = {
+  number = function()
+    error("The '^' operator is not currently supported for")
+  end,
+
+  string = function(left, right)
+    return right .. left
+  end,
+
+  array = function(left, right)
+    for i = #right, 1, -1 do
+      table.insert(left, 1, right[i])
+    end
+
+    return left
+  end,
+
+  map = tbl_merge,
+  set = tbl_merge,
+}
+
+--- Handles the '^' operator
+local function prepend_value(info, current, new)
+  return prepend_methods[info.metatype](
+    convert_value_to_lua(info, current),
+    convert_value_to_lua(info, new)
+  )
+end
+
+local add_methods = {
+  number = function(left, right)
+    return left + right
+  end,
+
+  string = function(left, right)
+    return left .. right
+  end,
+
+  array = function(left, right)
+    for _, v in ipairs(right) do
+      table.insert(left, v)
+    end
+
+    return left
+  end,
+
+  map = tbl_merge,
+  set = tbl_merge,
+}
+
+--- Handles the '+' operator
+local function add_value(info, current, new)
+  return add_methods[info.metatype](
+    convert_value_to_lua(info, current),
+    convert_value_to_lua(info, new)
+  )
+end
+
+local function remove_one_item(t, val)
+  if vim.tbl_islist(t) then
+    local remove_index = nil
+    for i, v in ipairs(t) do
+      if v == val then
+        remove_index = i
+      end
+    end
+
+    if remove_index then
+      table.remove(t, remove_index)
+    end
+  else
+    t[val] = nil
+  end
+end
+
+local remove_methods = {
+  number = function(left, right)
+    return left - right
+  end,
+
+  string = function()
+    error('Subtraction not supported for strings.')
+  end,
+
+  array = function(left, right)
+    if type(right) == 'string' then
+      remove_one_item(left, right)
+    else
+      for _, v in ipairs(right) do
+        remove_one_item(left, v)
+      end
+    end
+
+    return left
+  end,
+
+  map = tbl_remove,
+  set = tbl_remove,
+}
+
+--- Handles the '-' operator
+local function remove_value(info, current, new)
+  return remove_methods[info.metatype](convert_value_to_lua(info, current), new)
+end
+
+local function create_option_accessor(scope)
+  local option_mt
+
+  local function make_option(name, value)
+    local info = assert(options_info[name], 'Not a valid option name: ' .. name)
+
+    if type(value) == 'table' and getmetatable(value) == option_mt then
+      assert(name == value._name, "must be the same value, otherwise that's weird.")
+
+      value = value._value
+    end
+
+    return setmetatable({
+      _name = name,
+      _value = value,
+      _info = info,
+    }, option_mt)
+  end
+
+  option_mt = {
+    -- To set a value, instead use:
+    --  opt[my_option] = value
+    _set = function(self)
+      local value = convert_value_to_vim(self._name, self._info, self._value)
+      api.nvim_set_option_value(self._name, value, { scope = scope })
+    end,
+
+    get = function(self)
+      return convert_value_to_lua(self._info, self._value)
+    end,
+
+    append = function(self, right)
+      self._value = add_value(self._info, self._value, right)
+      self:_set()
+    end,
+
+    __add = function(self, right)
+      return make_option(self._name, add_value(self._info, self._value, right))
+    end,
+
+    prepend = function(self, right)
+      self._value = prepend_value(self._info, self._value, right)
+      self:_set()
+    end,
+
+    __pow = function(self, right)
+      return make_option(self._name, prepend_value(self._info, self._value, right))
+    end,
+
+    remove = function(self, right)
+      self._value = remove_value(self._info, self._value, right)
+      self:_set()
+    end,
+
+    __sub = function(self, right)
+      return make_option(self._name, remove_value(self._info, self._value, right))
+    end,
+  }
+  option_mt.__index = option_mt
+
+  return setmetatable({}, {
+    __index = function(_, k)
+      return make_option(k, api.nvim_get_option_value(k, {}))
+    end,
+
+    __newindex = function(_, k, v)
+      make_option(k, v):_set()
+    end,
+  })
+end
+
+vim.opt = create_option_accessor()
+vim.opt_local = create_option_accessor('local')
+vim.opt_global = create_option_accessor('global')