akkartik/mastodon-unfurl.love - Change KMSL74GAMFNTAKGDKZFP2AMQXUMOC3XH373BO4IABZWBEP3YAXKAC

support selections in the source editor

I've only tested side A so far, and included a statement of how I want side B to behave.

Created by Kartik K. Agaram on September 6, 2022

KMSL74GAMFNTAKGDKZFP2AMQXUMOC3XH373BO4IABZWBEP3YAXKAC

Dependencies

In channels

main

Change contents

Deletion in text.lua at line 934 [5.1]
∅:D[3.3710] → [4.5037:5077]
B:BD[4.5037] → [4.5037:5077]
```
--?   print('a', State.selection1.line)
```

Insertion in source_text_tests.lua at line 285 [6.3498]

[6.13887]

  check_nil(Editor_state.selection1.line, 'F - test_click_with_mouse/selection is empty to avoid perturbing future edits')

Insertion in source_text_tests.lua at line 304 [6.3498]

[6.14700]

  check_nil(Editor_state.selection1.line, 'F - test_click_with_mouse_to_left_of_line/selection is empty to avoid perturbing future edits')

Insertion in source_text_tests.lua at line 324 [6.3498]

[6.15604]

  check_nil(Editor_state.selection1.line, 'F - test_click_with_mouse_takes_margins_into_account/selection is empty to avoid perturbing future edits')

Insertion in source_text_tests.lua at line 414 [6.3498]

[6.19208]

  check_nil(Editor_state.selection1.line, 'F - test_click_with_mouse_on_wrapping_line/selection is empty to avoid perturbing future edits')

Insertion in source_text_tests.lua at line 434 [6.3498]

[6.20198]

  check_nil(Editor_state.selection1.line, 'F - test_click_with_mouse_on_wrapping_line_takes_margins_into_account/selection is empty to avoid perturbing future edits')

Insertion in source_text_tests.lua at line 591 [6.3498]

[6.27850]

end
function test_select_text()
  io.write('\ntest_select_text')
  -- display a line of text
  App.screen.init{width=75, height=80}
  Editor_state = edit.initialize_test_state()
  Editor_state.lines = load_array{'abc def'}
  Text.redraw_all(Editor_state)
  Editor_state.cursor1 = {line=1, pos=1}
  Editor_state.screen_top1 = {line=1, pos=1}
  Editor_state.screen_bottom1 = {}
  edit.draw(Editor_state)
  -- select a letter
  App.fake_key_press('lshift')
  edit.run_after_keychord(Editor_state, 'S-right')
  App.fake_key_release('lshift')
  edit.key_released(Editor_state, 'lshift')
  -- selection persists even after shift is released
  check_eq(Editor_state.selection1.line, 1, 'F - test_select_text/selection:line')
  check_eq(Editor_state.selection1.pos, 1, 'F - test_select_text/selection:pos')
  check_eq(Editor_state.cursor1.line, 1, 'F - test_select_text/cursor:line')
  check_eq(Editor_state.cursor1.pos, 2, 'F - test_select_text/cursor:pos')
end
function test_cursor_movement_without_shift_resets_selection()
  io.write('\ntest_cursor_movement_without_shift_resets_selection')
  -- display a line of text with some part selected
  App.screen.init{width=75, height=80}
  Editor_state = edit.initialize_test_state()
  Editor_state.lines = load_array{'abc'}
  Text.redraw_all(Editor_state)
  Editor_state.cursor1 = {line=1, pos=1}
  Editor_state.selection1 = {line=1, pos=2}
  Editor_state.screen_top1 = {line=1, pos=1}
  Editor_state.screen_bottom1 = {}
  edit.draw(Editor_state)
  -- press an arrow key without shift
  edit.run_after_keychord(Editor_state, 'right')
  -- no change to data, selection is reset
  check_nil(Editor_state.selection1.line, 'F - test_cursor_movement_without_shift_resets_selection')
  check_eq(Editor_state.lines[1].data, 'abc', 'F - test_cursor_movement_without_shift_resets_selection/data')

Insertion in source_text_tests.lua at line 635 [6.3498]

[6.27855]

function test_edit_deletes_selection()
  io.write('\ntest_edit_deletes_selection')
  -- display a line of text with some part selected
  App.screen.init{width=75, height=80}
  Editor_state = edit.initialize_test_state()
  Editor_state.lines = load_array{'abc'}
  Text.redraw_all(Editor_state)
  Editor_state.cursor1 = {line=1, pos=1}
  Editor_state.selection1 = {line=1, pos=2}
  Editor_state.screen_top1 = {line=1, pos=1}
  Editor_state.screen_bottom1 = {}
  edit.draw(Editor_state)
  -- press a key
  edit.run_after_textinput(Editor_state, 'x')
  -- selected text is deleted and replaced with the key
  check_eq(Editor_state.lines[1].data, 'xbc', 'F - test_edit_deletes_selection')
end
function test_edit_with_shift_key_deletes_selection()
  io.write('\ntest_edit_with_shift_key_deletes_selection')
  -- display a line of text with some part selected
  App.screen.init{width=75, height=80}
  Editor_state = edit.initialize_test_state()
  Editor_state.lines = load_array{'abc'}
  Text.redraw_all(Editor_state)
  Editor_state.cursor1 = {line=1, pos=1}
  Editor_state.selection1 = {line=1, pos=2}
  Editor_state.screen_top1 = {line=1, pos=1}
  Editor_state.screen_bottom1 = {}
  edit.draw(Editor_state)
  -- mimic precise keypresses for a capital letter
  App.fake_key_press('lshift')
  edit.keychord_pressed(Editor_state, 'd', 'd')
  edit.textinput(Editor_state, 'D')
  edit.key_released(Editor_state, 'd')
  App.fake_key_release('lshift')
  -- selected text is deleted and replaced with the key
  check_nil(Editor_state.selection1.line, 'F - test_edit_with_shift_key_deletes_selection')
  check_eq(Editor_state.lines[1].data, 'Dbc', 'F - test_edit_with_shift_key_deletes_selection/data')
end
function test_copy_does_not_reset_selection()
  io.write('\ntest_copy_does_not_reset_selection')
  -- display a line of text with a selection
  App.screen.init{width=75, height=80}
  Editor_state = edit.initialize_test_state()
  Editor_state.lines = load_array{'abc'}
  Text.redraw_all(Editor_state)
  Editor_state.cursor1 = {line=1, pos=1}
  Editor_state.selection1 = {line=1, pos=2}
  Editor_state.screen_top1 = {line=1, pos=1}
  Editor_state.screen_bottom1 = {}
  edit.draw(Editor_state)
  -- copy selection
  edit.run_after_keychord(Editor_state, 'C-c')
  check_eq(App.clipboard, 'a', 'F - test_copy_does_not_reset_selection/clipboard')
  -- selection is reset since shift key is not pressed
  check(Editor_state.selection1.line, 'F - test_copy_does_not_reset_selection')
end
function test_cut()
  io.write('\ntest_cut')
  -- display a line of text with some part selected
  App.screen.init{width=75, height=80}
  Editor_state = edit.initialize_test_state()
  Editor_state.lines = load_array{'abc'}
  Text.redraw_all(Editor_state)
  Editor_state.cursor1 = {line=1, pos=1}
  Editor_state.selection1 = {line=1, pos=2}
  Editor_state.screen_top1 = {line=1, pos=1}
  Editor_state.screen_bottom1 = {}
  edit.draw(Editor_state)
  -- press a key
  edit.run_after_keychord(Editor_state, 'C-x')
  check_eq(App.clipboard, 'a', 'F - test_cut/clipboard')
  -- selected text is deleted
  check_eq(Editor_state.lines[1].data, 'bc', 'F - test_cut/data')
end
function test_paste_replaces_selection()
  io.write('\ntest_paste_replaces_selection')
  -- display a line of text with a selection
  App.screen.init{width=75, height=80}
  Editor_state = edit.initialize_test_state()
  Editor_state.lines = load_array{'abc', 'def'}
  Text.redraw_all(Editor_state)
  Editor_state.cursor1 = {line=2, pos=1}
  Editor_state.selection1 = {line=1, pos=1}
  Editor_state.screen_top1 = {line=1, pos=1}
  Editor_state.screen_bottom1 = {}
  edit.draw(Editor_state)
  -- set clipboard
  App.clipboard = 'xyz'
  -- paste selection
  edit.run_after_keychord(Editor_state, 'C-v')
  -- selection is reset since shift key is not pressed
  -- selection includes the newline, so it's also deleted
  check_eq(Editor_state.lines[1].data, 'xyzdef', 'F - test_paste_replaces_selection')
end
function test_deleting_selection_may_scroll()
  io.write('\ntest_deleting_selection_may_scroll')
  -- display lines 2/3/4
  App.screen.init{width=120, height=60}
  Editor_state = edit.initialize_test_state()
  Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
  Text.redraw_all(Editor_state)
  Editor_state.cursor1 = {line=3, pos=2}
  Editor_state.screen_top1 = {line=2, pos=1}
  Editor_state.screen_bottom1 = {}
  edit.draw(Editor_state)
  local y = Editor_state.top
  App.screen.check(y, 'def', 'F - test_deleting_selection_may_scroll/baseline/screen:1')
  y = y + Editor_state.line_height
  App.screen.check(y, 'ghi', 'F - test_deleting_selection_may_scroll/baseline/screen:2')
  y = y + Editor_state.line_height
  App.screen.check(y, 'jkl', 'F - test_deleting_selection_may_scroll/baseline/screen:3')
  -- set up a selection starting above the currently displayed page
  Editor_state.selection1 = {line=1, pos=2}
  -- delete selection
  edit.run_after_keychord(Editor_state, 'backspace')
  -- page scrolls up
  check_eq(Editor_state.screen_top1.line, 1, 'F - test_deleting_selection_may_scroll')
  check_eq(Editor_state.lines[1].data, 'ahi', 'F - test_deleting_selection_may_scroll/data')
end

Insertion in source_text_tests.lua at line 868 [6.3498]
[6.32776]
[6.32776]
```
  Editor_state.selection1 = {}
```

Replacement in source_text_tests.lua at line 870 [6.3498]

B:BD[6.32871] → [6.32871:32957]

  edit.run_after_mouse_press(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)

[6.32871]

[6.32957]

  edit.run_after_mouse_release(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)

Insertion in source_text_tests.lua at line 873 [6.3498]

[6.33133]

  check_nil(Editor_state.selection1.line, 'F - test_move_cursor_using_mouse/selection:line')
  check_nil(Editor_state.selection1.pos, 'F - test_move_cursor_using_mouse/selection:pos')
end
function test_select_text_using_mouse()
  io.write('\ntest_select_text_using_mouse')
  App.screen.init{width=50, height=60}
  Editor_state = edit.initialize_test_state()
  Editor_state.lines = load_array{'abc', 'def', 'xyz'}
  Text.redraw_all(Editor_state)
  Editor_state.cursor1 = {line=1, pos=1}
  Editor_state.screen_top1 = {line=1, pos=1}
  Editor_state.screen_bottom1 = {}
  Editor_state.selection1 = {}
  edit.draw(Editor_state)  -- populate line_cache.starty for each line Editor_state.line_cache
  -- press and hold on first location
  edit.run_after_mouse_press(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
  -- drag and release somewhere else
  edit.run_after_mouse_release(Editor_state, Editor_state.left+20,Editor_state.top+Editor_state.line_height+5, 1)
  check_eq(Editor_state.selection1.line, 1, 'F - test_select_text_using_mouse/selection:line')
  check_eq(Editor_state.selection1.pos, 2, 'F - test_select_text_using_mouse/selection:pos')
  check_eq(Editor_state.cursor1.line, 2, 'F - test_select_text_using_mouse/cursor:line')
  check_eq(Editor_state.cursor1.pos, 4, 'F - test_select_text_using_mouse/cursor:pos')
end
function test_select_text_using_mouse_and_shift()
  io.write('\ntest_select_text_using_mouse_and_shift')
  App.screen.init{width=50, height=60}
  Editor_state = edit.initialize_test_state()
  Editor_state.lines = load_array{'abc', 'def', 'xyz'}
  Text.redraw_all(Editor_state)
  Editor_state.cursor1 = {line=1, pos=1}
  Editor_state.screen_top1 = {line=1, pos=1}
  Editor_state.screen_bottom1 = {}
  Editor_state.selection1 = {}
  edit.draw(Editor_state)  -- populate line_cache.starty for each line Editor_state.line_cache
  -- click on first location
  edit.run_after_mouse_press(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
  edit.run_after_mouse_release(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
  -- hold down shift and click somewhere else
  App.fake_key_press('lshift')
  edit.run_after_mouse_press(Editor_state, Editor_state.left+20,Editor_state.top+5, 1)
  edit.run_after_mouse_release(Editor_state, Editor_state.left+20,Editor_state.top+Editor_state.line_height+5, 1)
  App.fake_key_release('lshift')
  check_eq(Editor_state.selection1.line, 1, 'F - test_select_text_using_mouse_and_shift/selection:line')
  check_eq(Editor_state.selection1.pos, 2, 'F - test_select_text_using_mouse_and_shift/selection:pos')
  check_eq(Editor_state.cursor1.line, 2, 'F - test_select_text_using_mouse_and_shift/cursor:line')
  check_eq(Editor_state.cursor1.pos, 4, 'F - test_select_text_using_mouse_and_shift/cursor:pos')
end
function test_select_text_repeatedly_using_mouse_and_shift()
  io.write('\ntest_select_text_repeatedly_using_mouse_and_shift')
  App.screen.init{width=50, height=60}
  Editor_state = edit.initialize_test_state()
  Editor_state.lines = load_array{'abc', 'def', 'xyz'}
  Text.redraw_all(Editor_state)
  Text.redraw_all(Editor_state)
  Editor_state.cursor1 = {line=1, pos=1}
  Editor_state.screen_top1 = {line=1, pos=1}
  Editor_state.screen_bottom1 = {}
  Editor_state.selection1 = {}
  edit.draw(Editor_state)  -- populate line_cache.starty for each line Editor_state.line_cache
  -- click on first location
  edit.run_after_mouse_press(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
  edit.run_after_mouse_release(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
  -- hold down shift and click on a second location
  App.fake_key_press('lshift')
  edit.run_after_mouse_press(Editor_state, Editor_state.left+20,Editor_state.top+5, 1)
  edit.run_after_mouse_release(Editor_state, Editor_state.left+20,Editor_state.top+Editor_state.line_height+5, 1)
  -- hold down shift and click at a third location
  App.fake_key_press('lshift')
  edit.run_after_mouse_press(Editor_state, Editor_state.left+20,Editor_state.top+5, 1)
  edit.run_after_mouse_release(Editor_state, Editor_state.left+8,Editor_state.top+Editor_state.line_height+5, 1)
  App.fake_key_release('lshift')
  -- selection is between first and third location. forget the second location, not the first.
  check_eq(Editor_state.selection1.line, 1, 'F - test_select_text_repeatedly_using_mouse_and_shift/selection:line')
  check_eq(Editor_state.selection1.pos, 2, 'F - test_select_text_repeatedly_using_mouse_and_shift/selection:pos')
  check_eq(Editor_state.cursor1.line, 2, 'F - test_select_text_repeatedly_using_mouse_and_shift/cursor:line')
  check_eq(Editor_state.cursor1.pos, 2, 'F - test_select_text_repeatedly_using_mouse_and_shift/cursor:pos')

Insertion in source_text_tests.lua at line 954 [6.3498]

[6.33138]

function test_cut_without_selection()
  io.write('\ntest_cut_without_selection')
  -- display a few lines
  App.screen.init{width=Editor_state.left+30, height=60}
  Editor_state = edit.initialize_test_state()
  Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
  Text.redraw_all(Editor_state)
  Editor_state.cursor1 = {line=1, pos=2}
  Editor_state.screen_top1 = {line=1, pos=1}
  Editor_state.screen_bottom1 = {}
  Editor_state.selection1 = {}
  edit.draw(Editor_state)
  -- try to cut without selecting text
  edit.run_after_keychord(Editor_state, 'C-x')
  -- no crash
  check_nil(Editor_state.selection1.line, 'F - test_cut_without_selection')
end

Replacement in source_text_tests.lua at line 1714 [6.3498]

B:BD[6.73266] → [6.73266:73379]

  edit.run_after_mouse_press(Editor_state, Editor_state.left+8,Editor_state.top+Editor_state.line_height*2+5, 1)

[6.73266]

[6.73379]

  edit.run_after_mouse_release(Editor_state, Editor_state.left+8,Editor_state.top+Editor_state.line_height*2+5, 1)

Insertion in source_text_tests.lua at line 1791 [6.3498]

[6.77283]

-- 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=Editor_state.left+30, height=60}
  Editor_state = edit.initialize_test_state()
  Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl', 'mno'}
  Text.redraw_all(Editor_state)
  Editor_state.cursor1 = {line=1, pos=1}
  Editor_state.selection1 = {line=1, pos=2}
  -- backspace deletes the selected character, even though it's after the cursor
  edit.run_after_keychord(Editor_state, 'backspace')
  check_eq(Editor_state.lines[1].data, 'bc', "F - test_backspace_over_selection/data")
  -- cursor (remains) at start of selection
  check_eq(Editor_state.cursor1.line, 1, "F - test_backspace_over_selection/cursor:line")
  check_eq(Editor_state.cursor1.pos, 1, "F - test_backspace_over_selection/cursor:pos")
  -- selection is cleared
  check_nil(Editor_state.selection1.line, "F - test_backspace_over_selection/selection")
end
function test_backspace_over_selection_reverse()
  io.write('\ntest_backspace_over_selection_reverse')
  -- select just one character within a line with cursor after selection
  App.screen.init{width=Editor_state.left+30, height=60}
  Editor_state = edit.initialize_test_state()
  Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl', 'mno'}
  Text.redraw_all(Editor_state)
  Editor_state.cursor1 = {line=1, pos=2}
  Editor_state.selection1 = {line=1, pos=1}
  -- backspace deletes the selected character
  edit.run_after_keychord(Editor_state, 'backspace')
  check_eq(Editor_state.lines[1].data, 'bc', "F - test_backspace_over_selection_reverse/data")
  -- cursor moves to start of selection
  check_eq(Editor_state.cursor1.line, 1, "F - test_backspace_over_selection_reverse/cursor:line")
  check_eq(Editor_state.cursor1.pos, 1, "F - test_backspace_over_selection_reverse/cursor:pos")
  -- selection is cleared
  check_nil(Editor_state.selection1.line, "F - test_backspace_over_selection_reverse/selection")
end
function test_backspace_over_multiple_lines()
  io.write('\ntest_backspace_over_multiple_lines')
  -- select just one character within a line with cursor after selection
  App.screen.init{width=Editor_state.left+30, height=60}
  Editor_state = edit.initialize_test_state()
  Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl', 'mno'}
  Text.redraw_all(Editor_state)
  Editor_state.cursor1 = {line=1, pos=2}
  Editor_state.selection1 = {line=4, pos=2}
  -- backspace deletes the region and joins the remaining portions of lines on either side
  edit.run_after_keychord(Editor_state, 'backspace')
  check_eq(Editor_state.lines[1].data, 'akl', "F - test_backspace_over_multiple_lines/data:1")
  check_eq(Editor_state.lines[2].data, 'mno', "F - test_backspace_over_multiple_lines/data:2")
  -- cursor remains at start of selection
  check_eq(Editor_state.cursor1.line, 1, "F - test_backspace_over_multiple_lines/cursor:line")
  check_eq(Editor_state.cursor1.pos, 2, "F - test_backspace_over_multiple_lines/cursor:pos")
  -- selection is cleared
  check_nil(Editor_state.selection1.line, "F - test_backspace_over_multiple_lines/selection")
end
function test_backspace_to_end_of_line()
  io.write('\ntest_backspace_to_end_of_line')
  -- select region from cursor to end of line
  App.screen.init{width=Editor_state.left+30, height=60}
  Editor_state = edit.initialize_test_state()
  Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl', 'mno'}
  Text.redraw_all(Editor_state)
  Editor_state.cursor1 = {line=1, pos=2}
  Editor_state.selection1 = {line=1, pos=4}
  -- backspace deletes rest of line without joining to any other line
  edit.run_after_keychord(Editor_state, 'backspace')
  check_eq(Editor_state.lines[1].data, 'a', "F - test_backspace_to_start_of_line/data:1")
  check_eq(Editor_state.lines[2].data, 'def', "F - test_backspace_to_start_of_line/data:2")
  -- cursor remains at start of selection
  check_eq(Editor_state.cursor1.line, 1, "F - test_backspace_to_start_of_line/cursor:line")
  check_eq(Editor_state.cursor1.pos, 2, "F - test_backspace_to_start_of_line/cursor:pos")
  -- selection is cleared
  check_nil(Editor_state.selection1.line, "F - test_backspace_to_start_of_line/selection")
end
function test_backspace_to_start_of_line()
  io.write('\ntest_backspace_to_start_of_line')
  -- select region from cursor to start of line
  App.screen.init{width=Editor_state.left+30, height=60}
  Editor_state = edit.initialize_test_state()
  Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl', 'mno'}
  Text.redraw_all(Editor_state)
  Editor_state.cursor1 = {line=2, pos=1}
  Editor_state.selection1 = {line=2, pos=3}
  -- backspace deletes beginning of line without joining to any other line
  edit.run_after_keychord(Editor_state, 'backspace')
  check_eq(Editor_state.lines[1].data, 'abc', "F - test_backspace_to_start_of_line/data:1")
  check_eq(Editor_state.lines[2].data, 'f', "F - test_backspace_to_start_of_line/data:2")
  -- cursor remains at start of selection
  check_eq(Editor_state.cursor1.line, 2, "F - test_backspace_to_start_of_line/cursor:line")
  check_eq(Editor_state.cursor1.pos, 1, "F - test_backspace_to_start_of_line/cursor:pos")
  -- selection is cleared
  check_nil(Editor_state.selection1.line, "F - test_backspace_to_start_of_line/selection")
end

Insertion in source_text_tests.lua at line 1906 [6.3498]

[6.77924]

  check_nil(Editor_state.selection1.line, 'F - test_undo_insert_text/baseline/selection:line')
  check_nil(Editor_state.selection1.pos, 'F - test_undo_insert_text/baseline/selection:pos')

Insertion in source_text_tests.lua at line 1918 [6.3498]

[6.78471]

  check_nil(Editor_state.selection1.line, 'F - test_undo_insert_text/selection:line')
  check_nil(Editor_state.selection1.pos, 'F - test_undo_insert_text/selection:pos')

Insertion in source_text_tests.lua at line 1941 [6.3498]

[6.79393]

  check_nil(Editor_state.selection1.line, 'F - test_undo_delete_text/baseline/selection:line')
  check_nil(Editor_state.selection1.pos, 'F - test_undo_delete_text/baseline/selection:pos')

Insertion in source_text_tests.lua at line 1954 [6.3498]

[6.79991]

  check_nil(Editor_state.selection1.line, 'F - test_undo_delete_text/selection:line')
  check_nil(Editor_state.selection1.pos, 'F - test_undo_delete_text/selection:pos')
--?   check_eq(Editor_state.selection1.line, 2, 'F - test_undo_delete_text/selection:line')
--?   check_eq(Editor_state.selection1.pos, 4, 'F - test_undo_delete_text/selection:pos')

Insertion in source_text_tests.lua at line 1966 [6.3498]

[6.80291]

function test_undo_restores_selection()
  io.write('\ntest_undo_restores_selection')
  -- display a line of text with some part selected
  App.screen.init{width=75, height=80}
  Editor_state = edit.initialize_test_state()
  Editor_state.lines = load_array{'abc'}
  Text.redraw_all(Editor_state)
  Editor_state.cursor1 = {line=1, pos=1}
  Editor_state.selection1 = {line=1, pos=2}
  Editor_state.screen_top1 = {line=1, pos=1}
  Editor_state.screen_bottom1 = {}
  edit.draw(Editor_state)
  -- delete selected text
  edit.run_after_textinput(Editor_state, 'x')
  check_eq(Editor_state.lines[1].data, 'xbc', 'F - test_undo_restores_selection/baseline')
  check_nil(Editor_state.selection1.line, 'F - test_undo_restores_selection/baseline:selection')
  -- undo
  edit.run_after_keychord(Editor_state, 'C-z')
  edit.run_after_keychord(Editor_state, 'C-z')
  -- selection is restored
  check_eq(Editor_state.selection1.line, 1, 'F - test_undo_restores_selection/line')
  check_eq(Editor_state.selection1.pos, 2, 'F - test_undo_restores_selection/pos')
end

Insertion in source_text.lua at line 112 [6.83723]

[6.88179]

      end
      if State.selection1.line then
        local lo, hi = Text.clip_selection(State, line_index, pos, pos+frag_len)
        Text.draw_highlight(State, line, x,y, pos, lo,hi)

Insertion in source_text.lua at line 178 [6.83723]

[6.90125]

      end
      if State.selection1.line then
        local lo, hi = Text.clip_selection(State, line_index, pos, pos+frag_len)
        Text.draw_highlight(State, line, x,y, pos, lo,hi)

Replacement in source_text.lua at line 386 [6.83723]
B:BD[6.98781] → [6.98781:98809]
```
--?   print('chord', chord)
```
[6.98781]
[6.98809]
```
--?   print('chord', chord, State.selection1.line, State.selection1.pos)
```
Insertion in source_text.lua at line 392 [6.83723]
[6.98992]
[6.98992]
```
    State.selection1 = {}
```

Insertion in source_text.lua at line 410 [6.83723]

[6.100077]

    if State.selection1.line then
      Text.delete_selection(State, State.left, State.right)
      schedule_save(State)
      return
    end

Insertion in source_text.lua at line 473 [6.83723]

[6.103057]

    if State.selection1.line then
      Text.delete_selection(State, State.left, State.right)
      schedule_save(State)
      return
    end

Insertion in source_text.lua at line 526 [6.83723]
[6.105544]
[6.105544]
```
    State.selection1 = {}
```
Insertion in source_text.lua at line 529 [6.83723]
[6.105597]
[6.105597]
```
    State.selection1 = {}
```

Insertion in source_text.lua at line 531 [6.83723]

[6.105629]

    if State.selection1.line == nil then
      State.selection1 = {line=State.cursor1.line, pos=State.cursor1.pos, posB=State.cursor1.posB}
    end

Insertion in source_text.lua at line 536 [6.83723]

[6.105683]

    if State.selection1.line == nil then
      State.selection1 = {line=State.cursor1.line, pos=State.cursor1.pos, posB=State.cursor1.posB}
    end

Insertion in source_text.lua at line 543 [6.83723]
[6.105818]
[6.105818]
```
    State.selection1 = {}
```
Insertion in source_text.lua at line 546 [6.83723]
[6.105878]
[6.105878]
```
    State.selection1 = {}
```

Insertion in source_text.lua at line 548 [6.83723]

[6.105912]

    if State.selection1.line == nil then
      State.selection1 = {line=State.cursor1.line, pos=State.cursor1.pos, posB=State.cursor1.posB}
    end

Insertion in source_text.lua at line 553 [6.83723]

[6.105973]

    if State.selection1.line == nil then
      State.selection1 = {line=State.cursor1.line, pos=State.cursor1.pos, posB=State.cursor1.posB}
    end

Insertion in source_text.lua at line 559 [6.83723]
[6.106060]
[6.106060]
```
    State.selection1 = {}
```
Insertion in source_text.lua at line 562 [6.83723]
[6.106117]
[6.106117]
```
    State.selection1 = {}
```

Insertion in source_text.lua at line 564 [6.83723]

[6.106149]

    if State.selection1.line == nil then
      State.selection1 = {line=State.cursor1.line, pos=State.cursor1.pos, posB=State.cursor1.posB}
    end

Insertion in source_text.lua at line 569 [6.83723]

[6.106210]

    if State.selection1.line == nil then
      State.selection1 = {line=State.cursor1.line, pos=State.cursor1.pos, posB=State.cursor1.posB}
    end

Insertion in source_text.lua at line 575 [6.83723]
[6.106285]
[6.106285]
```
    State.selection1 = {}
```
Insertion in source_text.lua at line 578 [6.83723]
[6.106336]
[6.106336]
```
    State.selection1 = {}
```

Insertion in source_text.lua at line 580 [6.83723]

[6.106366]

    if State.selection1.line == nil then
      State.selection1 = {line=State.cursor1.line, pos=State.cursor1.pos, posB=State.cursor1.posB}
    end

Insertion in source_text.lua at line 585 [6.83723]

[6.106417]

    if State.selection1.line == nil then
      State.selection1 = {line=State.cursor1.line, pos=State.cursor1.pos, posB=State.cursor1.posB}
    end

Insertion in source_text.lua at line 591 [6.83723]
[6.106493]
[6.106493]
```
    State.selection1 = {}
```
Insertion in source_text.lua at line 594 [6.83723]
[6.106552]
[6.106552]
```
    State.selection1 = {}
```

Insertion in source_text.lua at line 596 [6.83723]

[6.106586]

    if State.selection1.line == nil then
      State.selection1 = {line=State.cursor1.line, pos=State.cursor1.pos, posB=State.cursor1.posB}
    end

Insertion in source_text.lua at line 601 [6.83723]

[6.106645]

    if State.selection1.line == nil then
      State.selection1 = {line=State.cursor1.line, pos=State.cursor1.pos, posB=State.cursor1.posB}
    end

File addition: source_select.lua (----------)

[7.2]

-- helpers for selecting portions of text
-- To keep things simple, we'll ignore the B side when selections start on the
-- A side, and stick to within a single B side selections start in.
-- Return any intersection of the region from State.selection1 to State.cursor1 (or
-- current mouse, if mouse is pressed; or recent mouse if mouse is pressed and
-- currently over a drawing) with the region between {line=line_index, pos=apos}
-- and {line=line_index, pos=bpos}.
-- apos must be less than bpos. However State.selection1 and State.cursor1 can be in any order.
-- Result: positions spos,epos between apos,bpos.
function Text.clip_selection(State, line_index, apos, bpos)
  if State.selection1.line == nil then return nil,nil end
  -- min,max = sorted(State.selection1,State.cursor1)
  local minl,minp = State.selection1.line,State.selection1.pos
  local maxl,maxp
  if App.mouse_down(1) then
    maxl,maxp = Text.mouse_pos(State)
  else
    maxl,maxp = State.cursor1.line,State.cursor1.pos
  end
  if Text.lt1({line=maxl, pos=maxp},
              {line=minl, pos=minp}) then
    minl,maxl = maxl,minl
    minp,maxp = maxp,minp
  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
-- draw highlight for line corresponding to (lo,hi) given an approximate x,y and pos on the same screen line
-- Creates text objects every time, so use this sparingly.
-- Returns some intermediate computation useful elsewhere.
function Text.draw_highlight(State, line, x,y, pos, lo,hi)
  if lo then
    local lo_offset = Text.offset(line.data, lo)
    local hi_offset = Text.offset(line.data, hi)
    local pos_offset = Text.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)
    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)
    App.color(Highlight_color)
    love.graphics.rectangle('fill', x+lo_px,y, text_width,State.line_height)
    App.color(Text_color)
    return lo_px
  end
end
-- inefficient for some reason, so don't do it on every frame
function Text.mouse_pos(State)
  local time = love.timer.getTime()
  if State.recent_mouse.time and State.recent_mouse.time > time-0.1 then
    return State.recent_mouse.line, State.recent_mouse.pos
  end
  State.recent_mouse.time = time
  local line,pos = Text.to_pos(State, App.mouse_x(), App.mouse_y())
  if line then
    State.recent_mouse.line = line
    State.recent_mouse.pos = pos
  end
  return State.recent_mouse.line, State.recent_mouse.pos
end
function Text.to_pos(State, x,y)
  for line_index,line in ipairs(State.lines) do
    if line.mode == 'text' then
      if Text.in_line(State, line_index, x,y) then
        return line_index, Text.to_pos_on_line(State, line_index, x,y)
      end
    end
  end
end
function Text.cut_selection(State)
  if State.selection1.line == nil then return end
  local result = Text.selection(State)
  Text.delete_selection(State)
  return result
end
function Text.delete_selection(State)
  if State.selection1.line == nil then return end
  local minl,maxl = minmax(State.selection1.line, State.cursor1.line)
  local before = snapshot(State, minl, maxl)
  Text.delete_selection_without_undo(State)
  record_undo_event(State, {before=before, after=snapshot(State, State.cursor1.line)})
end
function Text.delete_selection_without_undo(State)
  if State.selection1.line == nil then return end
  -- min,max = sorted(State.selection1,State.cursor1)
  local minl,minp = State.selection1.line,State.selection1.pos
  local maxl,maxp = State.cursor1.line,State.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 State.cursor1 and State.selection1
  State.cursor1.line = minl
  State.cursor1.pos = minp
  if Text.lt1(State.cursor1, State.screen_top1) then
    State.screen_top1.line = State.cursor1.line
    State.screen_top1.pos = Text.pos_at_start_of_screen_line(State, State.cursor1)
  end
  State.selection1 = {}
  -- delete everything between min (inclusive) and max (exclusive)
  Text.clear_screen_line_cache(State, minl)
  local min_offset = Text.offset(State.lines[minl].data, minp)
  local max_offset = Text.offset(State.lines[maxl].data, maxp)
  if minl == maxl then
--?     print('minl == maxl')
    State.lines[minl].data = State.lines[minl].data:sub(1, min_offset-1)..State.lines[minl].data:sub(max_offset)
    return
  end
  assert(minl < maxl)
  local rhs = State.lines[maxl].data:sub(max_offset)
  for i=maxl,minl+1,-1 do
    table.remove(State.lines, i)
    table.remove(State.line_cache, i)
  end
  State.lines[minl].data = State.lines[minl].data:sub(1, min_offset-1)..rhs
end
function Text.selection(State)
  if State.selection1.line == nil then return end
  -- min,max = sorted(State.selection1,State.cursor1)
  local minl,minp = State.selection1.line,State.selection1.pos
  local maxl,maxp = State.cursor1.line,State.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
  local min_offset = Text.offset(State.lines[minl].data, minp)
  local max_offset = Text.offset(State.lines[maxl].data, maxp)
  if minl == maxl then
    return State.lines[minl].data:sub(min_offset, max_offset-1)
  end
  assert(minl < maxl)
  local result = {State.lines[minl].data:sub(min_offset)}
  for i=minl+1,maxl-1 do
    if State.lines[i].mode == 'text' then
      table.insert(result, State.lines[i].data)
    end
  end
  table.insert(result, State.lines[maxl].data:sub(1, max_offset-1))
  return table.concat(result, '\n')
end

Insertion in source_edit.lua at line 78 [6.152440]

[6.154730]


    selection1 = {},
    -- some extra state to compute selection between mouse press and release
    old_cursor1 = nil,
    old_selection1 = nil,
    mousepress_shift = nil,
    -- when selecting text, avoid recomputing some state on every single frame
    recent_mouse = {},

Insertion in source_edit.lua at line 219 [6.152440]

[2.21646]

        -- delicate dance between cursor, selection and old cursor/selection
        -- scenarios:
        --  regular press+release: sets cursor, clears selection
        --  shift press+release:
        --    sets selection to old cursor if not set otherwise leaves it untouched
        --    sets cursor
        --  press and hold to start a selection: sets selection on press, cursor on release
        --  press and hold, then press shift: ignore shift
        --    i.e. mouse_released should never look at shift state
        State.old_cursor1 = State.cursor1
        State.old_selection1 = State.selection1
        State.mousepress_shift = App.shift_down()

Replacement in source_edit.lua at line 233 [6.152440]

B:BD[2.21781] → [2.21781:21843]

        State.cursor1 = {line=line_index, pos=pos, posB=posB}

[2.21781]

[2.21843]

        State.selection1 = {line=line_index, pos=pos, posB=posB}
--?         print('selection', State.selection1.line, State.selection1.pos, State.selection1.posB)

Insertion in source_edit.lua at line 260 [6.152440]

[2.22639]

  else
    for line_index,line in ipairs(State.lines) do
      if line.mode == 'text' then
        if Text.in_line(State, line_index, x,y) then
--?           print('reset selection')
          local pos,posB = Text.to_pos_on_line(State, line_index, x, y)
          State.cursor1 = {line=line_index, pos=pos, posB=posB}
--?           print('cursor', State.cursor1.line, State.cursor1.pos, State.cursor1.posB)
          if State.mousepress_shift then
            if State.old_selection1.line == nil then
              State.selection1 = State.old_cursor1
            else
              State.selection1 = State.old_selection1
            end
          end
          State.old_cursor1, State.old_selection1, State.mousepress_shift = nil
          if eq(State.cursor1, State.selection1) then
            State.selection1 = {}
          end
          break
        end
      end
    end
--?     print('selection:', State.selection1.line, State.selection1.pos)

Insertion in source_edit.lua at line 306 [6.152440]

[6.158146]

  if State.selection1.line and
      not State.lines.current_drawing and
      -- printable character created using shift key => delete selection
      -- (we're not creating any ctrl-shift- or alt-shift- combinations using regular/printable keys)
      (not App.shift_down() or utf8.len(key) == 1) and
      chord ~= 'C-c' and chord ~= 'C-x' and chord ~= 'backspace' and backspace ~= 'delete' and not App.is_cursor_movement(chord) then
    Text.delete_selection(State, State.left, State.right)
  end

Insertion in source_edit.lua at line 392 [6.152440]
[6.161052]
[6.161052]
```
      State.selection1 = deepcopy(src.selection)
```
Insertion in source_edit.lua at line 408 [6.152440]
[6.161625]
[6.161625]
```
      State.selection1 = deepcopy(src.selection)
```

Replacement in main.lua at line 63 [8.2]

B:BD[6.186396] → [6.186396:186458]

        load_file_from_source_or_save_directory('select.lua')

[6.186396]

[6.186458]

        load_file_from_source_or_save_directory('source_select.lua')