akkartik/lines-and-links - Change VJ77YABHVJZWJKLHAGIPC562GYM73AUGRLCP4JLKP5JPWPT2RIHAC

more efficient undo/redo

Now the bottleneck shifts to applying undo/redo in large files. But things should be snappy if you don't use the sluggish feature.

Created by Kartik K. Agaram on June 2, 2022

VJ77YABHVJZWJKLHAGIPC562GYM73AUGRLCP4JLKP5JPWPT2RIHAC

Dependencies

In channels

main

Change contents

Insertion in undo.lua at line 35 [5.1]
[5.1004]
[5.1004]
```
-- Copy all relevant global state.
```

Replacement in undo.lua at line 37 [5.1]

B:BD[5.1116] → [4.1:21]

function snapshot()

[5.1116]

[5.1147]

function snapshot(s,e)
  -- Snapshot everything by default, but subset if requested.
  if s == nil and e == nil then
    s = 1
    e = #Lines
  elseif e == nil then
    e = s
  end

Insertion in undo.lua at line 54 [5.1]
[5.1427]
[5.1427]
```
    start_line=s,
    end_line=e,
```
Replacement in undo.lua at line 59 [5.1]
B:BD[5.1559] → [5.1559:1592]
```
  for _,line in ipairs(Lines) do
```
[5.1559]
[5.1592]
```
  for i=s,e do
    local line = Lines[i]
```

Insertion in undo.lua at line 78 [5.1]

[5.2322]

function patch(lines, from, to)
--?   if #from.lines == 1 and #to.lines == 1 then
--?     assert(from.start_line == from.end_line)
--?     assert(to.start_line == to.end_line)
--?     assert(from.start_line == to.start_line)
--?     lines[from.start_line] = to.lines[1]
--?     return
--?   end
  assert(from.start_line == to.start_line)
  for i=from.end_line,from.start_line,-1 do
    table.remove(lines, i)
  end
  assert(#to.lines == to.end_line-to.start_line+1)
  for i=1,#to.lines do
    table.insert(lines, to.start_line+i-1, to.lines[i])
  end
end

Insertion in undo.lua at line 108 [5.1]

[5.2739]


function minmax(a, b)
  return math.min(a,b), math.max(a,b)
end

Insertion in text.lua at line 135 [7.1]

[6.2657]

  local minl,maxl = minmax(Selection1.line, Cursor1.line)
  local before = snapshot(minl, maxl)
  Text.delete_selection_without_undo()
  record_undo_event({before=before, after=snapshot(Cursor1.line)})
end
function Text.delete_selection_without_undo()

Deletion in text.lua at line 1178 [7.1]

B:BD[5.6254] → [3.2:614]

end
function test_zzz_undo_load_test()
  print('\n\nTesting a 10KB file')
  -- create a large list of lines
  local lines = {}
  -- 10k characters, hundred lines, 2k words
  for i=1,100 do
    local line = ''
    for c=1,20 do
      line = line..'abcd '
    end
  end
  Lines = load_array(lines)
  -- perform 1000 mutations
  print('are the dots printing quickly and without any pauses?')
  for i=1,1000 do
    if i%50 == 0 then
      App.run_after_keychord('return')
    else
      App.run_after_textinput('a')
    end
    if i%10 == 0 then
      io.write(i)
      io.write(' ')
      io.flush()
    end
  end

Replacement in text.lua at line 1225 [7.1]

∅:D[2.74] → [8.42:78]

B:BD[8.42] → [8.42:78]

  local down = love.keyboard.isDown

[2.74]

[9.1]

  if Selection1.line then
    Text.delete_selection()
  end
  local before = snapshot(Cursor1.line)

Insertion in text.lua at line 1230 [7.1]

[9.28]

[9.60]

  record_undo_event({before=before, after=snapshot(Cursor1.line)})

Deletion in text.lua at line 1234 [7.1]

B:BD[9.99] → [10.1:55]

B:BD[10.55] → [5.6260:6318]

B:BD[5.6318] → [4.23:51]

  if Selection1.line then Text.delete_selection() end
  -- Collect what you did in an event that can be undone.
  local before = snapshot()

Deletion in text.lua at line 1244 [7.1]
B:BD[11.763] → [5.6358:6383]
B:BD[5.6383] → [4.52:107]
```
  -- finalize undo event
  record_undo_event({before=before, after=snapshot()})
```

Replacement in text.lua at line 1251 [7.1]

B:BD[12.655] → [4.108:138]

    local before = snapshot()

[12.655]

[11.764]

    local before_line = Cursor1.line
    local before = snapshot(before_line)

Replacement in text.lua at line 1265 [7.1]

B:BD[13.1648] → [4.139:196]

    record_undo_event({before=before, after=snapshot()})

[13.1648]

[9.134]

    record_undo_event({before=before, after=snapshot(before_line, Cursor1.line)})

Replacement in text.lua at line 1267 [7.1]
B:BD[9.163] → [4.197:227]
```
    local before = snapshot()
```
[9.163]
[9.163]
```
    local before = snapshot(Cursor1.line)
```

Replacement in text.lua at line 1270 [7.1]

B:BD[12.1006] → [4.228:285]

    record_undo_event({before=before, after=snapshot()})

[12.1006]

[12.2046]

    record_undo_event({before=before, after=snapshot(Cursor1.line)})

Deletion in text.lua at line 1272 [7.1]
B:BD[12.2081] → [4.286:316]
```
    local before = snapshot()
```

Deletion in text.lua at line 1275 [7.1]

B:BD[5.6750] → [4.317:376]

      record_undo_event({before=before, after=snapshot()})

Insertion in text.lua at line 1277 [7.1]
[6.8474]
[11.1902]
```
    local before
```

Insertion in text.lua at line 1279 [7.1]

[11.1930]

      before = snapshot(Cursor1.line)
    else
      before = snapshot(Cursor1.line-1, Cursor1.line)
    end
    if Cursor1.pos > 1 then

Replacement in text.lua at line 1314 [7.1]

B:BD[12.3034] → [4.377:434]

    record_undo_event({before=before, after=snapshot()})

[12.3034]

    record_undo_event({before=before, after=snapshot(Cursor1.line)})

Deletion in text.lua at line 1316 [7.1]
B:BD[12.3066] → [4.435:465]
```
    local before = snapshot()
```

Deletion in text.lua at line 1319 [7.1]

B:BD[5.6968] → [4.466:525]

      record_undo_event({before=before, after=snapshot()})

Insertion in text.lua at line 1320 [7.1]

[6.8546]

    end
    local before
    if Cursor1.pos <= utf8.len(Lines[Cursor1.line].data) then
      before = snapshot(Cursor1.line)
    else
      before = snapshot(Cursor1.line, Cursor1.line+1)

Replacement in text.lua at line 1350 [7.1]

B:BD[12.3956] → [4.526:583]

    record_undo_event({before=before, after=snapshot()})

[12.3956]

[5.7107]

    record_undo_event({before=before, after=snapshot(Cursor1.line)})

Replacement in text.lua at line 1360 [7.1]

B:BD[5.7450] → [5.7450:7520]

      if src.lines then
        Lines = deepcopy(src.lines)
      end

[5.7450]

[5.7520]

      patch(Lines, event.after, event.before)

Replacement in text.lua at line 1369 [7.1]

B:BD[5.7761] → [5.7761:8113]

      if src.lines then
        Lines = deepcopy(src.lines)
--?         for _,line in ipairs(Lines) do
--?           if line.mode == 'drawing' then
--?             print('restoring', line.points, 'with', #line.points, 'points')
--?             print('restoring', line.shapes, 'with', #line.shapes, 'shapes')
--?           end
--?         end
      end

[5.7761]

[5.8113]

      patch(Lines, event.before, event.after)

Insertion in text.lua at line 1383 [7.1]

[14.76]

    local before_line = Cursor1.line
    local before = snapshot(before_line)

Insertion in text.lua at line 1389 [7.1]

[14.209]

    record_undo_event({before=before, after=snapshot(before_line, Cursor1.line)})

Replacement in README.md at line 9 [15.6]

B:BD[5.8364] → [5.8364:8558]

* Undo is extremely inefficient in space. While this app is extremely unlikely
  to lose the current state of a file at any moment, undo history is volatile
  and should be considered unstable.

[5.8364]

[16.14]

* Undo/redo can be sluggish in large files. If things get sluggish, killing
  the process can lose data.