akkartik/techmeet.love - Change HKDQTCZCPWZFU65UTDPOT3RRMTJ2TSWSCOAXFTAWICPD4GKZ3VJQC

new bug: screen_bottom1 might never be written

Scenario: press C-f and search for something. Some of the time we get a crash with this call stack:

Error text.lua:970: attempt to compare nil with number

Traceback [love "callbacks.lua"]:228: in function 'handler' text.lua:970: in function 'lt1' search.lua:72: in function 'search_next' run.lua:985: in function 'search_next_in_pane' run.lua:939: in function 'search_next' run.lua:784: in function 'text_input' main.lua:237: in function <main.lua:230> app.lua:31: in function <app.lua:22> [C]: in function 'xpcall'

Not fixed yet.

The cause: plan_draw is conservative and sometimes tries to render panes that never overlap the viewport.

This bug was exacerbated by fixing the inscript bug which started setting screen_bottom1 to nil. But the problem existed before as well, we just operated on stale screen_bottom1 locations.

This bug doesn't generalize to many other scenarios. It isn't a problem for forks without the surface metaphor, though it might affect driver.love as well. Even in pensieve.love, the only place that uses screen_bottom while spanning multiple editors is find across the entire surface.

Created by Kartik K. Agaram on June 10, 2023

HKDQTCZCPWZFU65UTDPOT3RRMTJ2TSWSCOAXFTAWICPD4GKZ3VJQC

Dependencies

In channels

main

Change contents

Insertion in text.lua at line 970 [6.1]

[5.293]

  if a.line == nil or b.line == nil then
    print_and_log(('Text.lt: found a nil line: %s %s'):format(tostring(a.line), tostring(b.line)))
  end

Insertion in text.lua at line 979 [6.1]

[5.390]

  if a.pos == nil or b.pos == nil then
    print_and_log('Text.lt: found a nil pos: ', a.pos, b.pos)
  end

Insertion in search.lua at line 27 [9.48846]
[7.39]
[8.721]
```
  local s = tostring
```

Insertion in search.lua at line 29 [9.48846]

[8.758]

[3.1372]

  print_and_log(('Text.search_next: %s,%s'):format(s(State.cursor1.line), s(State.cursor1.pos)))

Insertion in search.lua at line 35 [9.48846]

[3.1623]

    print_and_log(('Text.search_next: a %s,%s'):format(s(State.cursor1.line), s(State.cursor1.pos)))

Insertion in search.lua at line 39 [9.48846]

[3.1703]

[8.759]

    print_and_log(('Text.search_next: b %s,%s'):format(s(State.cursor1.line), s(State.cursor1.pos)))

Insertion in search.lua at line 51 [9.48846]

[3.1955]

[9.50096]

    print_and_log(('Text.search_next: c %s,%s'):format(s(State.cursor1.line), s(State.cursor1.pos)))

Insertion in search.lua at line 63 [9.48846]

[3.2207]

[8.793]

    print_and_log(('Text.search_next: d %s,%s'):format(s(State.cursor1.line), s(State.cursor1.pos)))

Insertion in search.lua at line 73 [9.48846]

[3.2429]

[7.489]

    print_and_log(('Text.search_next: e %s,%s'):format(s(State.cursor1.line), s(State.cursor1.pos)))

Insertion in search.lua at line 79 [9.48846]

[9.50515]

[7.730]

  print_and_log(('Text.search_next: f %s %s,%s %s,%s %s,%s'):format(State.id, s(State.cursor1.line), s(State.cursor1.pos), s(State.screen_top1.line), s(State.screen_top1.pos), s(State.screen_bottom1.line), s(State.screen_bottom1.pos)))

Replacement in run.lua at line 293 [11.178044]
∅:D[2.38] → [10.17:42]
B:BD[12.223] → [10.17:42]
∅:D[13.38] → [14.72:128]
∅:D[10.42] → [14.72:128]
∅:D[15.66] → [14.72:128]
∅:D[12.257] → [14.72:128]
∅:D[16.490] → [14.72:128]
B:BD[14.72] → [14.72:128]
```
--?   print('plan draw')
--?   print(#Surface, 'columns;', num_panes(), 'panes')
```
[2.38]
[14.128]
```
  print_and_log(('plan_draw %d,%d'):format(Display_settings.x, Display_settings.y))
```

Replacement in run.lua at line 306 [11.178044]

B:BD[17.13285] → [17.13285:13347]

--?         print('bounds:', column_index, pane_index, sx,sy)

[17.13285]

[17.13347]

        print_and_log(('plan_draw bounds %d,%d %s %d,%d'):format(column_index, pane_index, pane.id, sx,sy))

Insertion in edit.lua at line 164 [20.413]

[18.2727]

[19.15]

  print_and_log(('edit.draw %s %d %d,%d'):format(State.id, State.top, State.left,State.right))

Insertion in edit.lua at line 218 [20.413]

[21.2054]

[4.36]

  print_and_log(('edit.draw screen bottom %s %s,%s'):format(State.id, screen_bottom1.line, screen_bottom1.pos))