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