edit.lua

   1 local M = {}
   2
   3 -- XXX: in Lua 5.2 unpack() was moved into table
   4 local unpack = unpack or table.unpack
   5
   6 local function startof(node) return node.start end
   7 local function finishof(node) return node.finish end
   8 local function is_comment(node) return node.is_comment end
   9
  10 function M.new(parser, walker, fmt, insert, delete)
  11
  12         local function normalize_spacing(start, delta, list)
  13                 if delta > 0 then
  14                         table.insert(list, {start + delta, -delta})
  15                 elseif delta < 0 then
  16                         table.insert(list, {start, -delta})
  17                 end
  18                 return delta
  19         end
  20
  21         local function reindent_list(parent, base_indent, deltas, keep_electric_space)
  22                 local adj = 0
  23                 local pstart = parent.start + (parent.p and #parent.p or 0) + #parent.d
  24                 if parent.is_empty then
  25                         normalize_spacing(pstart, parent.finish - pstart, deltas)
  26                         return deltas
  27                 end
  28                 for i, s in ipairs(parent) do
  29                         local delta
  30                         adj = s.indent and 0 or adj
  31                         local prev = parent[i - 1]
  32                         if not s.indent and not (prev and (s.d == "|" or prev.d == "|")) then
  33                                 -- remove/add leading spaces
  34                                 local off = prev and prev.finish + 1 or pstart
  35                                 adj = adj + normalize_spacing(off, s.start - off - (prev and 1 or 0), deltas)
  36                         end
  37                         local nxt = parent[i + 1]
  38                         local is_last = not nxt
  39                         if (is_last and not keep_electric_space) or nxt and nxt.indent then
  40                                 -- clean up trailing spaces
  41                                 local has_eol = s.is_comment and parser.opposite[s.d]:find("\n")  -- grep -n XYZZ\Y *.lua
  42                                 local off = is_last and parent.finish - (has_eol and 1 or 0) or nxt.start - nxt.indent - 1
  43                                 local finish = s.finish + (has_eol and 0 or 1)
  44                                 normalize_spacing(finish, off - finish, deltas)
  45                         end
  46                         if s.indent then
  47                                 delta = base_indent - s.indent
  48                                 local last_distinguished = fmt:last_distinguished(parent)
  49                                 if last_distinguished then
  50                                         delta = delta + 1
  51                                         if i - 1 <= last_distinguished then
  52                                                 delta = delta + 2
  53                                         end
  54                                 elseif                               -- align further arguments below the second one
  55                                         parent.d == "("              -- [] and {} contain data, so no arguments
  56                                         and not parent[1].is_string  -- a string can't have arguments
  57                                         --and not parent[1].is_list  -- wrong, GNU Emacs compatible behaviour
  58                                         then
  59                                         if i > 2 and not parent[2].indent then
  60                                                 delta = base_indent + parent[2].start - pstart - s.indent
  61                                         end
  62                                 end
  63                                 if delta < 0 then delta = math.max(-s.indent, delta) end
  64                                 if delta ~= 0 then
  65                                         table.insert(deltas, {s.start, delta})
  66                                 end
  67                                 adj = adj - delta
  68                         end
  69                         if s.is_list then
  70                                 local nearest_indented = s.indent and s or walker.indented_before(s)
  71                                 local parent_column = nearest_indented.indent + (s.start + (s.p and #s.p or 0) + #s.d) - nearest_indented.start
  72                                 reindent_list(s, parent_column - adj, deltas, keep_electric_space)
  73                         end
  74                 end
  75                 return deltas
  76         end
  77
  78         -- FIXME: when called at the end of another operation, some nested lists do not get reindented
  79         local function reindent_at(scope, range, keep_electric_space)
  80                 if not range or scope.is_root then return end
  81                 local parent = walker.sexp_at(scope, true)
  82                 if not (parent and parent.is_list) then return end
  83                 local _, parent_at, m = walker.sexp_at(range, true)
  84                 if not m then
  85                         _, m = parent_at.after(range.start, startof)
  86                         if not m then
  87                                 m = #parent_at
  88                         end
  89                 end
  90                 local base = parent_at[m] or parent_at
  91                 local path = walker.sexp_path(base)
  92                 local after_start, at_pfinish
  93                 if parent_at[m] then
  94                         local s = parent_at[#parent_at]
  95                         local has_eol = s.is_comment and parser.opposite[s.d]:find("\n")  -- grep -n XYZZ\Y *.lua
  96                         if range.start >= s.finish + 1 + (has_eol and 1 or 0) then
  97                                 at_pfinish = true
  98                         else
  99                                 after_start = range.start < base.start and 0 or range.start - base.start
 100                         end
 101                 else
 102                         after_start = (parent_at.p and #parent_at.p or 0) + #parent_at.d
 103                 end
 104                 local indented_parent = parent.indent and parent or parent.is_list and walker.indented_before(parent)
 105                 local parent_column = indented_parent and (indented_parent.indent + parent.start - indented_parent.start +
 106                         (parent.p and #parent.p or 0) + #parent.d) or
 107                         0
 108                 local deltas = reindent_list(parent, parent_column, {}, keep_electric_space)
 109                 table.sort(deltas, function(d1, d2) return d1[1] > d2[1] end)
 110                 for _, pair in ipairs(deltas) do
 111                         local offset, delta = unpack(pair)
 112                         if delta > 0 then
 113                                 insert(offset, string.rep(" ", delta))
 114                         elseif delta < 0 then
 115                                 delete(offset + delta, -delta)
 116                         end
 117                 end
 118                 parser.tree.rewind(parent.start or 0)
 119                 if path then
 120                         local sexp, parentng = walker.goto_path(path)
 121                         if sexp then
 122                                 if at_pfinish then
 123                                         return parentng.finish
 124                                 else
 125                                         return sexp.start + after_start
 126                                 end
 127                         end
 128                 end
 129                 return range.start
 130         end
 131
 132         local function splice(pos, sexps, skip, backwards, action)
 133                 local spliced
 134                 local sexp = walker.sexp_at(skip, true)
 135                 local start = sexp.start + (sexp.p and #sexp.p or 0)
 136                 local tosplice = action.splice or action.wrap or sexp.is_empty
 137                 local opening = (sexp.p or '')..sexp.d
 138                 local closing = parser.opposite[sexp.d]
 139                 local real_start = tosplice and sexp.start or start + #sexp.d
 140                 local splice_closing = not closing:find("\n") or sexp.is_empty
 141                 local real_finish = sexp.finish + 1 - (tosplice and splice_closing and 0 or #closing)
 142                 local first = backwards and
 143                         {start = real_start, finish = math.max(pos, start + #sexp.d)} or
 144                         {start = real_start, finish = sexp.is_empty and pos or start + #sexp.d}
 145                 local second = backwards and
 146                         {start = sexp.is_empty and pos or sexp.finish + 1 - #closing, finish = real_finish} or
 147                         {start = math.min(pos, sexp.finish + 1 - #closing), finish = real_finish}
 148                 action.func(second)
 149                 action.func(first)
 150                 spliced = tosplice
 151                 if action.kill then
 152                         local ndeleted = first.finish - first.start + second.finish - second.start
 153                         if ndeleted > 0 then
 154                                 sexps.rewind(sexp.start)
 155                         end
 156                 end
 157                 return first.finish - first.start, spliced, opening, closing
 158         end
 159
 160         local function pick_out(range, pos, action)
 161                 local sexps = parser.tree
 162                 local skips = sexps.unbalanced_delimiters(range)
 163                 -- handle splice and kill-splice of forms and strings:
 164                 if #skips == 1 then
 165                         local sexp = walker.sexp_at(skips[1], true)
 166                         local backward_splice = skips[1].opening and pos >= sexp.start + (sexp.p and #sexp.p or 0) + #sexp.d
 167                                 and range.start >= sexp.start
 168                         local forward_splice = skips[1].closing and pos <= sexp.finish + 1 - #parser.opposite[sexp.d]
 169                                 and range.finish <= sexp.finish + 1
 170                         if backward_splice or forward_splice then
 171                                 return splice(backward_splice and range.finish or range.start, sexps, sexp, backward_splice, action)
 172                         end
 173                 end
 174                 local node, parent = walker.sexp_at({start = range.finish, finish = range.finish})
 175                 local drop_eol = node and node.finish + 1 == range.finish and node.is_comment and parser.opposite[node.d]:find("\n")
 176                 table.sort(skips, function(a, b) return a.start < b.start end)
 177                 table.insert(skips, {start = range.finish - (drop_eol and 1 or 0)})  -- grep -n XYZZ\Y *.lua
 178                 table.insert(skips, 1, {finish = range.start})
 179                 local ndeleted = drop_eol and 1 or 0
 180                 for i = #skips - 1, 1, -1 do
 181                         local region = {start = skips[i].finish, finish = skips[i + 1].start}
 182                         if skips[i].closing and skips[i + 1].opening then
 183                                 -- leave out some of the space between adjacent lists
 184                                 local _, rparent = walker.sexp_at(region)
 185                                 local nxt = rparent.after(region.start, startof)
 186                                 region.start = nxt and nxt.start or region.start
 187                         end
 188                         if action then
 189                                 action.func(region)
 190                                 ndeleted = ndeleted + (region.finish - region.start)
 191                         end
 192                 end
 193                 -- if parent[#parent + 1] is nil, we are at EOF
 194                 if ndeleted > 0 and (not parent.is_root or parent[#parent + 1]) then
 195                         sexps.rewind(range.start)
 196                 end
 197                 return ndeleted
 198         end
 199
 200         local function raise_sexp(range, pos)
 201                 local sexp, parent = walker.sexp_at(range, true)
 202                 if sexp and parent and parent.is_list then
 203                         delete(sexp.finish + 1, parent.finish - sexp.finish)
 204                         delete(parent.start, sexp.start - parent.start)
 205                         parser.tree.rewind(parent.start)
 206                         range.start = parent.start + pos - sexp.start
 207                         range.finish = range.start
 208                         local _, parentng = walker.sexp_at(range, true)
 209                         local _, grandparent = walker.sexp_at(parentng, true)
 210                         return grandparent and reindent_at(grandparent, range) or range.start
 211                 end
 212         end
 213
 214         local function slurp_sexp(range, forward)
 215                 local _, parent = walker.sexp_at(range, true)
 216                 local seeker = forward and walker.finish_after or walker.start_before
 217                 if not parent or not parent.is_list then return range.start end
 218                 local r = {start = parent.start, finish = parent.finish + 1}
 219                 local newpos = seeker(r, is_comment)
 220                 if not newpos then return range.start end
 221                 local opening = (parent.p or '')..parent.d
 222                 local closing = parser.opposite[parent.d]
 223                 local delimiter = forward and closing or opening
 224                 if forward then
 225                         insert(newpos, delimiter)
 226                 end
 227                 delete(forward and parent.finish or parent.start, #delimiter)
 228                 if not forward then
 229                         insert(newpos, delimiter)
 230                 end
 231                 parser.tree.rewind(math.min(parent.start, newpos))
 232                 local _, parentng = walker.sexp_at(range, true)
 233                 return reindent_at(parentng, range)
 234         end
 235
 236         local function barf_sexp(range, forward)
 237                 local _, parent, m = walker.sexp_at(range, true)
 238                 local seeker = forward and walker.finish_before or walker.start_after
 239                 -- TODO: barfing out of strings requires calling the parser on them
 240                 if not parent or not parent.is_list then return range.start end
 241                 local opening = (parent.p or '')..parent.d
 242                 local pstart = parent.start + #opening
 243                 local r = {start = forward and parent.finish - 1 or pstart, finish = forward and parent.finish or pstart + 1}
 244                 local newpos = seeker(r, is_comment) or forward and pstart or parent.finish
 245                 if not newpos then return range.start end
 246                 local closing = parser.opposite[parent.d]
 247                 local delimiter = forward and closing or opening
 248                 if not forward then
 249                         insert(newpos, delimiter)
 250                 end
 251                 delete(forward and parent.finish or parent.start, #delimiter)
 252                 if forward then
 253                         insert(newpos, delimiter)
 254                 end
 255                 parser.tree.rewind(math.min(parent.start, newpos))
 256                 range.start = range.start + #delimiter *
 257                         (m == 1 and not forward and -1 or m == #parent and forward and 1 or 0)
 258                 local _, parentng = walker.sexp_at(range, true)
 259                 local _, grandparent = walker.sexp_at(parentng, true)
 260                 return reindent_at(grandparent, range) or range.start
 261         end
 262
 263         local function splice_sexp(range, _)
 264                 local _, parent = walker.sexp_at(range)
 265                 if not parent or not parent.d then return end
 266                 local opening = (parent.p or '')..parent.d
 267                 local closing = parser.opposite[parent.d]
 268                 local finish = parent.finish + 1 - #closing
 269                 if not closing:find("\n") then
 270                         delete(finish, #closing)
 271                 end
 272                 -- TODO: (un)escape special characters, if necessary
 273                 delete(parent.start, parent.is_empty and (finish - parent.start) or #opening)
 274                 parser.tree.rewind(parent.start)
 275                 range.start = range.start - #opening
 276                 range.finish = range.start
 277                 local _, parentng = walker.sexp_at(range, true)
 278                 return reindent_at(parentng, range)
 279         end
 280
 281         local function cycle_wrap(range, pos)
 282                 local _, parent = walker.sexp_at(range)
 283                 if not parent or not parent.is_list then return end
 284                 local pstart = parent.start + #((parent.p or '')..parent.d) - 1
 285                 local next_kind = {["("] = "[", ["["] = "{", ["{"] = "("}
 286                 delete(parent.finish, 1)
 287                 insert(parent.finish, parser.opposite[next_kind[parent.d]])
 288                 delete(pstart, #parent.d)
 289                 insert(pstart, next_kind[parent.d])
 290                 parser.tree.rewind(parent.start)
 291                 return pos
 292         end
 293
 294         local function split_sexp(range)
 295                 local _, parent = walker.sexp_at(range)
 296                 if not (parent and parent.d) then return end
 297                 local new_finish, new_start
 298                 if parent.is_list then
 299                         local prev = parent.before(range.start, finishof, is_comment)
 300                         new_finish = prev and prev.finish + 1
 301                         -- XXX: do not skip comments here, so they end up in the second list
 302                         -- and are not separated from their target expression:
 303                         local nxt = new_finish and parent.after(new_finish, startof)
 304                         new_start = nxt and nxt.start
 305                 else
 306                         new_start = range.start
 307                         new_finish = range.start
 308                 end
 309                 if not (new_start and new_finish) then return end
 310                 local opening = (parent.p or '')..parent.d
 311                 local closing = parser.opposite[parent.d]
 312                 insert(new_start, opening)
 313                 local sep = parser.opposite[parent.d]:find("\n") and ""  -- line comments already have a separator
 314                         or new_finish == new_start and " "  -- only add a separator if there was none before
 315                         or ""
 316                 insert(new_finish, closing..sep)
 317                 parser.tree.rewind(parent.start)
 318                 range.start = new_start + (parent.is_list and 0 or #opening + #closing)
 319                 range.finish = range.start
 320                 local _, parentng = walker.sexp_at(range, true)
 321                 local _, grandparent = walker.sexp_at(parentng, true)
 322                 return reindent_at(grandparent, range) or range.start
 323         end
 324
 325         local function join_sexps(range)
 326                 local node, parent = walker.sexp_at(range, true)
 327                 local first = node and node.finish + 1 == range.start and node or parent.before(range.start, finishof)
 328                 local second = first ~= node and node or parent.after(range.start, startof)
 329                 if not (first and second and first.d and
 330                         (first.d == second.d or
 331                                 -- join line comments even when their delimiters differ slightly
 332                                 -- (different number of ;'s, existence/lack of a space after them)
 333                                 first.d:find("^;") and second.d:find("^;"))) then
 334                         return
 335                 end
 336                 local opening = (second.p or '')..second.d
 337                 local closing = parser.opposite[first.d]
 338                 local pos
 339                 if not first.is_list then
 340                         pos = first.finish + 1 - #closing
 341                         delete(pos, second.start + #opening - pos)
 342                 else
 343                         delete(second.start, #opening)
 344                         delete(first.finish, #closing)
 345                         pos = second.start - #closing
 346                 end
 347                 parser.tree.rewind(first.start)
 348                 range.start = pos
 349                 range.finish = range.start
 350                 local _, parentng = walker.sexp_at(range, true)
 351                 local _, grandparent = walker.sexp_at(parentng, true)
 352                 return reindent_at(grandparent, range) or range.start
 353         end
 354
 355         local function delete_splicing(range, pos, splicing, delete_and_yank)
 356                 local action = {kill = true, wrap = splicing, splice = splicing, func = delete_and_yank}
 357                 local sexp, parent, n = walker.sexp_at(range, true)
 358                 local ndeleted, spliced = pick_out(range, pos, action)
 359                 local closing = spliced and parser.opposite[sexp.d]
 360                 local inner_list_len = spliced and sexp.finish - sexp.start + 1 - #sexp.d - #closing
 361                 local range_len = range.finish - range.start
 362                 local backwards = pos == range.finish
 363                 local whole_object = sexp and
 364                         (sexp.start == range.start and sexp.finish + 1 == range.finish
 365                         or spliced and (inner_list_len <= (backwards and range_len + ndeleted or range_len)))
 366                 local in_head_atom = sexp and not sexp.d and n == 1 and #parent > 1
 367                 local in_whitespace = not sexp
 368                 if whole_object or in_whitespace or in_head_atom then
 369                         local cur = whole_object and sexp.start or range.start
 370                         parser.tree.rewind(cur)
 371                         local r = {start = cur, finish = cur}
 372                         local _, parentng = walker.sexp_at(r, true)
 373                         local newpos = reindent_at(parentng, r)
 374                         return newpos or cur
 375                 end
 376                 return not backwards and ndeleted <= 0 and range.finish - ndeleted or range.start
 377         end
 378
 379         local function transpose(range, first, second)
 380                 if not (first and second) then return end
 381                 local copy1 = first.text
 382                 local copy2 = second.text
 383                 delete(second.start, second.finish + 1 - second.start)
 384                 insert(second.start, copy1)
 385                 delete(first.start, first.finish + 1 - first.start)
 386                 insert(first.start, copy2)
 387                 parser.tree.rewind(first.start)
 388                 range.start = second.finish + 1
 389                 range.finish = range.start
 390                 local _, parentng = walker.sexp_at(range, true)
 391                 return reindent_at(parentng, range) or range.start
 392         end
 393
 394         local function transpose_sexps(range)
 395                 local node, parent = walker.sexp_at(range, true)
 396                 local first = node and node.finish + 1 == range.start and node or parent.before(range.start, finishof)
 397                 local second = first ~= node and node or parent.after(range.start, startof)
 398                 return transpose(range, first, second)
 399         end
 400
 401         local function transpose_words(range)
 402                 local _, first = walker.start_float_before(range)
 403                 local _, second = walker.finish_float_after(range)
 404                 if first and second and first.start == second.start then
 405                         _, first = walker.start_float_before(first)
 406                 end
 407                 return transpose(range, first, second)
 408         end
 409
 410         local function transpose_chars(range)
 411                 local node, parent, i = walker.sexp_at(range)
 412                 local nxt = i and parent[i + 1]
 413                 local pstart = not parent.is_root and parent.start + (parent.p and #parent.p or 0) + #parent.d
 414                 local pfinish = not parent.is_root and parent.finish
 415                 local npref = node and node.p and node.start + #node.p
 416                 -- only allow transposing while inside atoms/words and prefixes
 417                 if node and ((npref and (range.start <= npref and range.start > node.start) or
 418                         node.d and range.start > node.finish + 1) or not node.d and (not pstart or range.start > pstart)) then
 419                         local start = range.start -
 420                                 ((range.start == pfinish or range.start == npref or
 421                                 range.start == node.finish + 1 and (parent.is_list or parent.is_root) and (not nxt or nxt.indent)) and 1 or 0)
 422                         local str_start = start - node.start + 1
 423                         local char = node.text:sub(str_start, str_start)
 424                         delete(start, 1)
 425                         insert(start - 1, #char > 0 and char or " ")
 426                         parser.tree.rewind(start)
 427                         local in_head_atom = i == 1 and #parent > 1
 428                         return parent.is_list and in_head_atom
 429                                 and reindent_at(parent, {start = start + 1, finish = start + 1})
 430                                 or start + 1
 431                 end
 432         end
 433
 434         local function delete_nonsplicing(range, pos, delete_maybe_yank)
 435                 local action = {kill = true, wrap = false, splice = false, func = delete_maybe_yank}
 436                 local ndeleted, spliced, opening = pick_out(range, pos, action)
 437                 local backwards = pos == range.finish
 438                 if opening then
 439                         if spliced then
 440                                 return pos - ndeleted
 441                         else
 442                                 if ndeleted == 0 then
 443                                         local sexp = walker.sexp_at(range)
 444                                         if sexp and sexp.d and sexp.d:match("^;") then
 445                                                 if pos == sexp.start + #sexp.d then
 446                                                         return join_sexps(range) or pos
 447                                                 elseif pos == sexp.finish then
 448                                                         local closing = parser.opposite[sexp.d]
 449                                                         local r = {start = pos + #closing, finish = pos + #closing}
 450                                                         return join_sexps(r) or pos + #closing
 451                                                 end
 452                                         end
 453                                 end
 454                                 return backwards and (range.finish - ndeleted) or range.start
 455                         end
 456                 else
 457                         return backwards and range.start or (range.finish - ndeleted)
 458                 end
 459         end
 460
 461         local function make_wrap(kind)
 462                 return function(range, pos, round_to_square)
 463                         local opening = kind
 464                         if kind == ";" then
 465                                 local node, parent = walker.sexp_at(range, true)
 466                                 if parent.is_root then
 467                                         -- FIXME: don't do that at the end of a defun
 468                                         opening = ";;; "
 469                                 else
 470                                         local nxt = parent.after(range.finish, startof)
 471                                         if not (nxt and nxt.indent and node and (node.finish + 1 <= range.start)) then
 472                                                 opening = ";; "
 473                                         end
 474                                 end
 475                         end
 476                         local function _wrap(r)
 477                                 local indices, nodes = walker.sexp_path(r)
 478                                 local delimiter, closing = opening, parser.opposite[opening]
 479                                 local squarewords = fmt.squarewords
 480                                 if closing ~= "}" and squarewords then
 481                                         if closing == ")" and (round_to_square or squarewords.not_optional)
 482                                                         and not fmt:rewrite_bracket_p(indices, nodes, range) then
 483                                                 delimiter, closing = "[", "]"
 484                                         end
 485                                 end
 486                                 insert(r.finish, closing)
 487                                 insert(r.start, delimiter)
 488                         end
 489                         local action = {kill = false, wrap = false, splice = false, func = _wrap}
 490                         pick_out(range, pos, action)
 491                         parser.tree.rewind(range.start)
 492                         local _, parentng = walker.sexp_at(range, true)
 493                         range.start = range.start + #opening
 494                         return reindent_at(parentng, range) or range.start
 495                 end
 496         end
 497
 498         return {
 499                 delete_splicing = delete_splicing,
 500                 delete_nonsplicing = delete_nonsplicing,
 501                 reindent_at = reindent_at,
 502                 pick_out = pick_out,
 503                 raise_sexp = raise_sexp,
 504                 slurp_sexp = slurp_sexp,
 505                 barf_sexp = barf_sexp,
 506                 splice_sexp = splice_sexp,
 507                 wrap_round = make_wrap("("),
 508                 meta_doublequote = make_wrap('"'),
 509                 comment_dwim = make_wrap(";"),
 510                 cycle_wrap = cycle_wrap,
 511                 split_sexp = split_sexp,
 512                 join_sexps = join_sexps,
 513                 transpose_sexps = transpose_sexps,
 514                 transpose_words = transpose_words,
 515                 transpose_chars = transpose_chars,
 516         }
 517 end
 518
 519 return M