-- change is saved

  -- undo is saved

  -- change is saved

  -- undo is saved

end
function test_undo_delete_point()
  io.write('\ntest_undo_delete_point')
  -- create a drawing with two lines connected at a point
  Filename = 'foo'
  App.screen.init{width=Margin_left+300, height=300}
  Lines = load_array{'```lines', '```', ''}
  Line_width = 256  -- drawing coordinates 1:1 with pixels
  Current_drawing_mode = 'line'
  App.draw()
  App.run_after_mouse_press(Margin_left+5, Margin_top+Drawing_padding_top+6, 1)
  App.run_after_mouse_release(Margin_left+35, Margin_top+Drawing_padding_top+36, 1)
  App.run_after_mouse_press(Margin_left+35, Margin_top+Drawing_padding_top+36, 1)
  App.run_after_mouse_release(Margin_left+55, Margin_top+Drawing_padding_top+26, 1)
  local drawing = Lines[1]
  check_eq(#drawing.shapes, 2, 'F - test_undo_delete_point/baseline/#shapes')
  check_eq(drawing.shapes[1].mode, 'line', 'F - test_undo_delete_point/baseline/shape:1')
  check_eq(drawing.shapes[2].mode, 'line', 'F - test_undo_delete_point/baseline/shape:2')
  -- hover on the common point and delete
  App.mouse_move(Margin_left+35, Margin_top+Drawing_padding_top+36)
  App.run_after_keychord('C-d')
  check_eq(drawing.shapes[1].mode, 'deleted', 'F - test_undo_delete_point/shape:1')
  check_eq(drawing.shapes[2].mode, 'deleted', 'F - test_undo_delete_point/shape:2')
  -- undo
  App.run_after_keychord('C-z')
  local drawing = Lines[1]
  local p2 = drawing.points[drawing.shapes[1].p2]
  check_eq(Next_history, 3, 'F - test_undo_move_point/next_history')
  check_eq(drawing.shapes[1].mode, 'line', 'F - test_undo_delete_point/shape:1')
  check_eq(drawing.shapes[2].mode, 'line', 'F - test_undo_delete_point/shape:2')
  -- undo is saved
  Lines = load_from_disk(Filename)
  check_eq(#Lines[1].shapes, 2, 'F - test_undo_delete_point/save')

program before it ever runs. However, some things don't have tests yet.

program before it ever runs. However, some things don't have tests yet, either
because I don't know how to test them or because I've been lazy. I'll at least
record those here.

undo:
  deleting points