akkartik/snap.love - Change DHI6IJCNSTHGED67T6H5X6Y636C7PIDGIJD32HBEKLT5WIMRS5MAC

selecting text and deleting selections

I've written a few tests for delete_selection, but the way different operations initialize the selection seems fairly standard and not worth testing so far.

Created by Kartik K. Agaram on May 29, 2022

DHI6IJCNSTHGED67T6H5X6Y636C7PIDGIJD32HBEKLT5WIMRS5MAC

Dependencies

In channels

main

Change contents

Insertion in text.lua at line 28 [6.1]
[5.62]
[2.1]
```
    local frag_len = utf8.len(frag)
```

Insertion in text.lua at line 48 [6.1]

[4.128]

[7.20]

      if Selection1.line then
        local lo, hi = Text.clip_selection(line_index, pos, pos+frag_len)
        if lo then
          local lo_offset = utf8.offset(line.data, lo)
          local hi_offset = utf8.offset(line.data, hi)
          local pos_offset = utf8.offset(line.data, pos)
          local lo_px
          if pos == lo then
            lo_px = 0
          else
            local before = line.data:sub(pos_offset, lo_offset-1)
            local before_text = App.newText(love.graphics.getFont(), before)
            lo_px = App.width(before_text)*Zoom
          end
--?           print(lo,pos,hi, '--', lo_offset,pos_offset,hi_offset, '--', lo_px)
          local s = line.data:sub(lo_offset, hi_offset-1)
          local text = App.newText(love.graphics.getFont(), s)
          local text_width = App.width(text)*Zoom
          love.graphics.setColor(0.7,0.7,0.9)
          love.graphics.rectangle('fill', x+lo_px,y, text_width,math.floor(15*Zoom))
          love.graphics.setColor(0,0,0)
        end
      end

Deletion in text.lua at line 75 [6.1]
B:BD[8.2288] → [8.2288:2324]
```
    local frag_len = utf8.len(frag)
```

Replacement in text.lua at line 90 [6.1]

B:BD[8.2728] → [8.2728:2796]

--  short words break on spaces
--  long words break when they must

[8.2728]

[9.100]


-- Return any intersection of the region from Selection1 to Cursor1 with the
-- region between {line=line_index, pos=apos} and {line=line_index, pos=bpos}.
-- apos must be less than bpos. However Selection1 and Cursor1 can be in any order.
-- Result: positions spos,epos between apos,bpos.
function Text.clip_selection(line_index, apos, bpos)
  if Selection1.line == nil then return nil,nil end
  -- min,max = sorted(Selection1,Cursor1)
  local minl,minp = Selection1.line,Selection1.pos
  local maxl,maxp = Cursor1.line,Cursor1.pos
  if minl > maxl then
    minl,maxl = maxl,minl
    minp,maxp = maxp,minp
  elseif minl == maxl then
    if minp > maxp then
      minp,maxp = maxp,minp
    end
  end
  -- check if intervals are disjoint
  if line_index < minl then return nil,nil end
  if line_index > maxl then return nil,nil end
  if line_index == minl and bpos <= minp then return nil,nil end
  if line_index == maxl and apos >= maxp then return nil,nil end
  -- compare bounds more carefully (start inclusive, end exclusive)
  local a_ge = Text.le1({line=minl, pos=minp}, {line=line_index, pos=apos})
  local b_lt = Text.lt1({line=line_index, pos=bpos}, {line=maxl, pos=maxp})
--?   print(minl,line_index,maxl, '--', minp,apos,bpos,maxp, '--', a_ge,b_lt)
  if a_ge and b_lt then
    -- fully contained
    return apos,bpos
  elseif a_ge then
    assert(maxl == line_index)
    return apos,maxp
  elseif b_lt then
    assert(minl == line_index)
    return minp,bpos
  else
    assert(minl == maxl and minl == line_index)
    return minp,maxp
  end
end
function Text.delete_selection()
  if Selection1.line == nil then return end
  -- min,max = sorted(Selection1,Cursor1)
  local minl,minp = Selection1.line,Selection1.pos
  local maxl,maxp = Cursor1.line,Cursor1.pos
  if minl > maxl then
    minl,maxl = maxl,minl
    minp,maxp = maxp,minp
  elseif minl == maxl then
    if minp > maxp then
      minp,maxp = maxp,minp
    end
  end
  -- update Cursor1 and Selection1
  Cursor1.line = minl
  Cursor1.pos = minp
  Selection1 = {}
  -- delete everything between min (inclusive) and max (exclusive)
  Lines[minl].fragments = nil
  Lines[minl].screen_line_starting_pos = nil
  local min_offset = utf8.offset(Lines[minl].data, minp)
  local max_offset = utf8.offset(Lines[maxl].data, maxp)
  if minl == maxl then
--?     print('minl == maxl')
    Lines[minl].data = Lines[minl].data:sub(1, min_offset-1)..Lines[minl].data:sub(max_offset)
    return
  end
  assert(minl < maxl)
  local rhs = Lines[maxl].data:sub(max_offset)
  for i=maxl,minl+1,-1 do
    table.remove(Lines, i)
  end
  Lines[minl].data = Lines[minl].data:sub(1, min_offset-1)..rhs
end

Insertion in text.lua at line 930 [6.1]

[10.2857]

[11.2046]

end
-- some tests for operating over selections created using Shift- chords
-- we're just testing delete_selection, and it works the same for all keys
function test_backspace_over_selection()
  io.write('\ntest_backspace_over_selection')
  -- select just one character within a line with cursor before selection
  App.screen.init{width=25+30, height=60}
  Lines = load_array{'abc', 'def', 'ghi', 'jkl', 'mno'}
  Line_width = App.screen.width
  Cursor1 = {line=1, pos=1}
  Selection1 = {line=1, pos=2}
  Zoom = 1
  -- backspace deletes the selected character, even though it's after the cursor
  App.run_after_keychord('backspace')
  check_eq(Lines[1].data, 'bc', "F - test_backspace_over_selection/data")
  -- cursor (remains) at start of selection
  check_eq(Cursor1.line, 1, "F - test_backspace_over_selection/cursor:line")
  check_eq(Cursor1.pos, 1, "F - test_backspace_over_selection/cursor:pos")
  -- selection is cleared
  check_nil(Selection1.line, "F - test_backspace_over_selection/selection")

Insertion in text.lua at line 954 [6.1]

[11.2051]

[12.1]

function test_backspace_over_selection_reverse()
  io.write('\ntest_backspace_over_selection')
  -- select just one character within a line with cursor after selection
  App.screen.init{width=25+30, height=60}
  Lines = load_array{'abc', 'def', 'ghi', 'jkl', 'mno'}
  Line_width = App.screen.width
  Cursor1 = {line=1, pos=2}
  Selection1 = {line=1, pos=1}
  Zoom = 1
  -- backspace deletes the selected character
  App.run_after_keychord('backspace')
  check_eq(Lines[1].data, 'bc', "F - test_backspace_over_selection_reverse/data")
  -- cursor moves to start of selection
  check_eq(Cursor1.line, 1, "F - test_backspace_over_selection_reverse/cursor:line")
  check_eq(Cursor1.pos, 1, "F - test_backspace_over_selection_reverse/cursor:pos")
  -- selection is cleared
  check_nil(Selection1.line, "F - test_backspace_over_selection_reverse/selection")
end
function test_backspace_over_multiple_lines()
  io.write('\ntest_backspace_over_selection')
  -- select just one character within a line with cursor after selection
  App.screen.init{width=25+30, height=60}
  Lines = load_array{'abc', 'def', 'ghi', 'jkl', 'mno'}
  Line_width = App.screen.width
  Cursor1 = {line=1, pos=2}
  Selection1 = {line=4, pos=2}
  Zoom = 1
  -- backspace deletes the region and joins the remaining portions of lines on either side
  App.run_after_keychord('backspace')
  check_eq(Lines[1].data, 'akl', "F - test_backspace_over_multiple_lines/data:1")
  check_eq(Lines[2].data, 'mno', "F - test_backspace_over_multiple_lines/data:2")
  -- cursor remains at start of selection
  check_eq(Cursor1.line, 1, "F - test_backspace_over_multiple_lines/cursor:line")
  check_eq(Cursor1.pos, 2, "F - test_backspace_over_multiple_lines/cursor:pos")
  -- selection is cleared
  check_nil(Selection1.line, "F - test_backspace_over_multiple_lines/selection")
end
function test_backspace_to_end_of_line()
  io.write('\ntest_backspace_over_selection')
  -- select region from cursor to end of line
  App.screen.init{width=25+30, height=60}
  Lines = load_array{'abc', 'def', 'ghi', 'jkl', 'mno'}
  Line_width = App.screen.width
  Cursor1 = {line=1, pos=2}
  Selection1 = {line=1, pos=4}
  Zoom = 1
  -- backspace deletes rest of line without joining to any other line
  App.run_after_keychord('backspace')
  check_eq(Lines[1].data, 'a', "F - test_backspace_to_start_of_line/data:1")
  check_eq(Lines[2].data, 'def', "F - test_backspace_to_start_of_line/data:2")
  -- cursor remains at start of selection
  check_eq(Cursor1.line, 1, "F - test_backspace_to_start_of_line/cursor:line")
  check_eq(Cursor1.pos, 2, "F - test_backspace_to_start_of_line/cursor:pos")
  -- selection is cleared
  check_nil(Selection1.line, "F - test_backspace_to_start_of_line/selection")
end
function test_backspace_to_start_of_line()
  io.write('\ntest_backspace_over_selection')
  -- select region from cursor to start of line
  App.screen.init{width=25+30, height=60}
  Lines = load_array{'abc', 'def', 'ghi', 'jkl', 'mno'}
  Line_width = App.screen.width
  Cursor1 = {line=2, pos=1}
  Selection1 = {line=2, pos=3}
  Zoom = 1
  -- backspace deletes beginning of line without joining to any other line
  App.run_after_keychord('backspace')
  check_eq(Lines[1].data, 'abc', "F - test_backspace_to_start_of_line/data:1")
  check_eq(Lines[2].data, 'f', "F - test_backspace_to_start_of_line/data:2")
  -- cursor remains at start of selection
  check_eq(Cursor1.line, 2, "F - test_backspace_to_start_of_line/cursor:line")
  check_eq(Cursor1.pos, 1, "F - test_backspace_to_start_of_line/cursor:pos")
  -- selection is cleared
  check_nil(Selection1.line, "F - test_backspace_to_start_of_line/selection")
end

Insertion in text.lua at line 1098 [6.1]
[13.627]
[14.1]
```
--?   print(chord)
```

Insertion in text.lua at line 1116 [6.1]

[13.2081]

[15.1902]

    if Selection1.line then
      Text.delete_selection()
      return
    end

Insertion in text.lua at line 1152 [6.1]

[13.3066]

[15.2805]

    if Selection1.line then
      Text.delete_selection()
      return
    end

Insertion in text.lua at line 1187 [6.1]

[14.277]

    if Selection1.line then
      Selection1 = {}
    end

Insertion in text.lua at line 1192 [6.1]

[14.324]

    if Selection1.line then
      Selection1 = {}
    end

Insertion in text.lua at line 1196 [6.1]

[14.341]

[14.369]

  elseif chord == 'S-left' then
    if Selection1.line == nil then
      Selection1 = {line=Cursor1.line, pos=Cursor1.pos}
    end
    Text.left()
  elseif chord == 'S-right' then
    if Selection1.line == nil then
      Selection1 = {line=Cursor1.line, pos=Cursor1.pos}
    end
    Text.right()

Insertion in text.lua at line 1208 [6.1]

[14.456]

[16.1]

    if Selection1.line then
      Selection1 = {}
    end

Insertion in text.lua at line 1213 [6.1]

[14.794]

[16.23]

    if Selection1.line then
      Selection1 = {}
    end

Insertion in text.lua at line 1217 [6.1]

[16.45]

[14.1073]

  elseif chord == 'M-S-left' then
    if Selection1.line == nil then
      Selection1 = {line=Cursor1.line, pos=Cursor1.pos}
    end
    Text.word_left()
  elseif chord == 'M-S-right' then
    if Selection1.line == nil then
      Selection1 = {line=Cursor1.line, pos=Cursor1.pos}
    end
    Text.word_right()

Insertion in text.lua at line 1228 [6.1]

[14.1103]

    if Selection1.line then
      Selection1 = {}
    end

Insertion in text.lua at line 1233 [6.1]

[14.1152]

    if Selection1.line then
      Selection1 = {}
    end

Insertion in text.lua at line 1237 [6.1]

[14.1209]

[13.3956]

  elseif chord == 'S-home' then
    if Selection1.line == nil then
      Selection1 = {line=Cursor1.line, pos=Cursor1.pos}
    end
    Cursor1.pos = 1
  elseif chord == 'S-end' then
    if Selection1.line == nil then
      Selection1 = {line=Cursor1.line, pos=Cursor1.pos}
    end
    Cursor1.pos = utf8.len(Lines[Cursor1.line].data) + 1

Insertion in text.lua at line 1248 [6.1]

[13.3984]

[16.46]

    if Selection1.line then
      Selection1 = {}
    end

Insertion in text.lua at line 1253 [6.1]

[13.4463]

[16.61]

    if Selection1.line then
      Selection1 = {}
    end
    Text.down()
  elseif chord == 'S-up' then
    if Selection1.line == nil then
      Selection1 = {line=Cursor1.line, pos=Cursor1.pos}
    end
    Text.up()
  elseif chord == 'S-down' then
    if Selection1.line == nil then
      Selection1 = {line=Cursor1.line, pos=Cursor1.pos}
    end

Insertion in text.lua at line 1268 [6.1]

[17.33]

[3.1]

    if Selection1.line then
      Selection1 = {}
    end

Insertion in text.lua at line 1273 [6.1]

[17.893]

[3.20]

    if Selection1.line then
      Selection1 = {}
    end
    Text.pagedown()
  elseif chord == 'S-pageup' then
    if Selection1.line == nil then
      Selection1 = {line=Cursor1.line, pos=Cursor1.pos}
    end
    Text.pageup()
  elseif chord == 'S-pagedown' then
    if Selection1.line == nil then
      Selection1 = {line=Cursor1.line, pos=Cursor1.pos}
    end

Replacement in text.lua at line 1439 [6.1]

B:BD[16.5453] → [16.5453:5516]

    if Lines[Cursor1.line].data:sub(offset,offset) == ' ' then

[16.5453]

[16.5516]

    if Lines[Cursor1.line].data:sub(offset,offset) == ' ' then  -- TODO: other space characters

Insertion in test.lua at line 11 [18.2]

[18.214]

  end
end
function check_nil(x, msg)
  if x == nil then
    io.write('.')
  else
    error(msg..'; should be nil but got "'..x..'"')

Insertion in main.lua at line 62 [20.2]
[15.9198]
[19.54]
```
Selection1 = {}
```

Insertion in main.lua at line 183 [20.2]

[21.492]

[22.1788]

        if love.keyboard.isDown('lshift') or love.keyboard.isDown('rshift') then
          if Selection1.line == nil then
            Selection1 = {line=Cursor1.line, pos=Cursor1.pos}
          end
        else
          if Selection1.line then
            Selection1 = {}
          end
        end