text_tests.lua

   1 -- major tests for text editing flows
   2
   3 function test_initial_state()
   4   App.screen.init{width=120, height=60}
   5   Editor_state = edit.initialize_test_state()
   6   Editor_state.lines = load_array{}
   7   Text.redraw_all(Editor_state)
   8   edit.draw(Editor_state)
   9   check_eq(#Editor_state.lines, 1, '#lines')
  10   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
  11   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
  12   check_eq(Editor_state.screen_top1.line, 1, 'screen_top:line')
  13   check_eq(Editor_state.screen_top1.pos, 1, 'screen_top:pos')
  14 end
  15
  16 function test_click_to_create_drawing()
  17   App.screen.init{width=120, height=60}
  18   Editor_state = edit.initialize_test_state()
  19   Editor_state.lines = load_array{}
  20   Text.redraw_all(Editor_state)
  21   edit.draw(Editor_state)
  22   edit.run_after_mouse_click(Editor_state, 8,Editor_state.top+8, 1)
  23   -- cursor skips drawing to always remain on text
  24   check_eq(#Editor_state.lines, 2, '#lines')
  25   check_eq(Editor_state.cursor1.line, 2, 'cursor')
  26 end
  27
  28 function test_backspace_to_delete_drawing()
  29   -- display a drawing followed by a line of text (you shouldn't ever have a drawing right at the end)
  30   App.screen.init{width=120, height=60}
  31   Editor_state = edit.initialize_test_state()
  32   Editor_state.lines = load_array{'```lines', '```', ''}
  33   Text.redraw_all(Editor_state)
  34   -- cursor is on text as always (outside tests this will get initialized correctly)
  35   Editor_state.cursor1.line = 2
  36   -- backspacing deletes the drawing
  37   edit.run_after_keychord(Editor_state, 'backspace')
  38   check_eq(#Editor_state.lines, 1, '#lines')
  39   check_eq(Editor_state.cursor1.line, 1, 'cursor')
  40 end
  41
  42 function test_backspace_from_start_of_final_line()
  43   -- display final line of text with cursor at start of it
  44   App.screen.init{width=120, height=60}
  45   Editor_state = edit.initialize_test_state()
  46   Editor_state.lines = load_array{'abc', 'def'}
  47   Editor_state.screen_top1 = {line=2, pos=1}
  48   Editor_state.cursor1 = {line=2, pos=1}
  49   Text.redraw_all(Editor_state)
  50   -- backspace scrolls up
  51   edit.run_after_keychord(Editor_state, 'backspace')
  52   check_eq(#Editor_state.lines, 1, '#lines')
  53   check_eq(Editor_state.cursor1.line, 1, 'cursor')
  54   check_eq(Editor_state.screen_top1.line, 1, 'screen_top')
  55 end
  56
  57 function test_insert_first_character()
  58   App.screen.init{width=120, height=60}
  59   Editor_state = edit.initialize_test_state()
  60   Editor_state.lines = load_array{}
  61   Text.redraw_all(Editor_state)
  62   edit.draw(Editor_state)
  63   edit.run_after_text_input(Editor_state, 'a')
  64   local y = Editor_state.top
  65   App.screen.check(y, 'a', 'screen:1')
  66 end
  67
  68 function test_press_ctrl()
  69   -- press ctrl while the cursor is on text
  70   App.screen.init{width=50, height=80}
  71   Editor_state = edit.initialize_test_state()
  72   Editor_state.lines = load_array{''}
  73   Text.redraw_all(Editor_state)
  74   Editor_state.cursor1 = {line=1, pos=1}
  75   Editor_state.screen_top1 = {line=1, pos=1}
  76   Editor_state.screen_bottom1 = {}
  77   edit.run_after_keychord(Editor_state, 'C-m')
  78 end
  79
  80 function test_move_left()
  81   App.screen.init{width=120, height=60}
  82   Editor_state = edit.initialize_test_state()
  83   Editor_state.lines = load_array{'a'}
  84   Text.redraw_all(Editor_state)
  85   Editor_state.cursor1 = {line=1, pos=2}
  86   edit.draw(Editor_state)
  87   edit.run_after_keychord(Editor_state, 'left')
  88   check_eq(Editor_state.cursor1.pos, 1, 'check')
  89 end
  90
  91 function test_move_right()
  92   App.screen.init{width=120, height=60}
  93   Editor_state = edit.initialize_test_state()
  94   Editor_state.lines = load_array{'a'}
  95   Text.redraw_all(Editor_state)
  96   Editor_state.cursor1 = {line=1, pos=1}
  97   edit.draw(Editor_state)
  98   edit.run_after_keychord(Editor_state, 'right')
  99   check_eq(Editor_state.cursor1.pos, 2, 'check')
 100 end
 101
 102 function test_move_left_to_previous_line()
 103   App.screen.init{width=120, height=60}
 104   Editor_state = edit.initialize_test_state()
 105   Editor_state.lines = load_array{'abc', 'def'}
 106   Text.redraw_all(Editor_state)
 107   Editor_state.cursor1 = {line=2, pos=1}
 108   edit.draw(Editor_state)
 109   edit.run_after_keychord(Editor_state, 'left')
 110   check_eq(Editor_state.cursor1.line, 1, 'line')
 111   check_eq(Editor_state.cursor1.pos, 4, 'pos')  -- past end of line
 112 end
 113
 114 function test_move_right_to_next_line()
 115   App.screen.init{width=120, height=60}
 116   Editor_state = edit.initialize_test_state()
 117   Editor_state.lines = load_array{'abc', 'def'}
 118   Text.redraw_all(Editor_state)
 119   Editor_state.cursor1 = {line=1, pos=4}  -- past end of line
 120   edit.draw(Editor_state)
 121   edit.run_after_keychord(Editor_state, 'right')
 122   check_eq(Editor_state.cursor1.line, 2, 'line')
 123   check_eq(Editor_state.cursor1.pos, 1, 'pos')
 124 end
 125
 126 function test_move_to_start_of_word()
 127   App.screen.init{width=120, height=60}
 128   Editor_state = edit.initialize_test_state()
 129   Editor_state.lines = load_array{'abc'}
 130   Text.redraw_all(Editor_state)
 131   Editor_state.cursor1 = {line=1, pos=3}
 132   edit.draw(Editor_state)
 133   edit.run_after_keychord(Editor_state, 'M-left')
 134   check_eq(Editor_state.cursor1.pos, 1, 'check')
 135 end
 136
 137 function test_move_to_start_of_previous_word()
 138   App.screen.init{width=120, height=60}
 139   Editor_state = edit.initialize_test_state()
 140   Editor_state.lines = load_array{'abc def'}
 141   Text.redraw_all(Editor_state)
 142   Editor_state.cursor1 = {line=1, pos=4}  -- at the space between words
 143   edit.draw(Editor_state)
 144   edit.run_after_keychord(Editor_state, 'M-left')
 145   check_eq(Editor_state.cursor1.pos, 1, 'check')
 146 end
 147
 148 function test_skip_to_previous_word()
 149   App.screen.init{width=120, height=60}
 150   Editor_state = edit.initialize_test_state()
 151   Editor_state.lines = load_array{'abc def'}
 152   Text.redraw_all(Editor_state)
 153   Editor_state.cursor1 = {line=1, pos=5}  -- at the start of second word
 154   edit.draw(Editor_state)
 155   edit.run_after_keychord(Editor_state, 'M-left')
 156   check_eq(Editor_state.cursor1.pos, 1, 'check')
 157 end
 158
 159 function test_skip_past_tab_to_previous_word()
 160   App.screen.init{width=120, height=60}
 161   Editor_state = edit.initialize_test_state()
 162   Editor_state.lines = load_array{'abc def\tghi'}
 163   Text.redraw_all(Editor_state)
 164   Editor_state.cursor1 = {line=1, pos=10}  -- within third word
 165   edit.draw(Editor_state)
 166   edit.run_after_keychord(Editor_state, 'M-left')
 167   check_eq(Editor_state.cursor1.pos, 9, 'check')
 168 end
 169
 170 function test_skip_multiple_spaces_to_previous_word()
 171   App.screen.init{width=120, height=60}
 172   Editor_state = edit.initialize_test_state()
 173   Editor_state.lines = load_array{'abc  def'}
 174   Text.redraw_all(Editor_state)
 175   Editor_state.cursor1 = {line=1, pos=6}  -- at the start of second word
 176   edit.draw(Editor_state)
 177   edit.run_after_keychord(Editor_state, 'M-left')
 178   check_eq(Editor_state.cursor1.pos, 1, 'check')
 179 end
 180
 181 function test_move_to_start_of_word_on_previous_line()
 182   App.screen.init{width=120, height=60}
 183   Editor_state = edit.initialize_test_state()
 184   Editor_state.lines = load_array{'abc def', 'ghi'}
 185   Text.redraw_all(Editor_state)
 186   Editor_state.cursor1 = {line=2, pos=1}
 187   edit.draw(Editor_state)
 188   edit.run_after_keychord(Editor_state, 'M-left')
 189   check_eq(Editor_state.cursor1.line, 1, 'line')
 190   check_eq(Editor_state.cursor1.pos, 5, 'pos')
 191 end
 192
 193 function test_move_past_end_of_word()
 194   App.screen.init{width=120, height=60}
 195   Editor_state = edit.initialize_test_state()
 196   Editor_state.lines = load_array{'abc def'}
 197   Text.redraw_all(Editor_state)
 198   Editor_state.cursor1 = {line=1, pos=1}
 199   edit.draw(Editor_state)
 200   edit.run_after_keychord(Editor_state, 'M-right')
 201   check_eq(Editor_state.cursor1.pos, 4, 'check')
 202 end
 203
 204 function test_skip_to_next_word()
 205   App.screen.init{width=120, height=60}
 206   Editor_state = edit.initialize_test_state()
 207   Editor_state.lines = load_array{'abc def'}
 208   Text.redraw_all(Editor_state)
 209   Editor_state.cursor1 = {line=1, pos=4}  -- at the space between words
 210   edit.draw(Editor_state)
 211   edit.run_after_keychord(Editor_state, 'M-right')
 212   check_eq(Editor_state.cursor1.pos, 8, 'check')
 213 end
 214
 215 function test_skip_past_tab_to_next_word()
 216   App.screen.init{width=120, height=60}
 217   Editor_state = edit.initialize_test_state()
 218   Editor_state.lines = load_array{'abc\tdef'}
 219   Text.redraw_all(Editor_state)
 220   Editor_state.cursor1 = {line=1, pos=1}  -- at the space between words
 221   edit.draw(Editor_state)
 222   edit.run_after_keychord(Editor_state, 'M-right')
 223   check_eq(Editor_state.cursor1.pos, 4, 'check')
 224 end
 225
 226 function test_skip_multiple_spaces_to_next_word()
 227   App.screen.init{width=120, height=60}
 228   Editor_state = edit.initialize_test_state()
 229   Editor_state.lines = load_array{'abc  def'}
 230   Text.redraw_all(Editor_state)
 231   Editor_state.cursor1 = {line=1, pos=4}  -- at the start of second word
 232   edit.draw(Editor_state)
 233   edit.run_after_keychord(Editor_state, 'M-right')
 234   check_eq(Editor_state.cursor1.pos, 9, 'check')
 235 end
 236
 237 function test_move_past_end_of_word_on_next_line()
 238   App.screen.init{width=120, height=60}
 239   Editor_state = edit.initialize_test_state()
 240   Editor_state.lines = load_array{'abc def', 'ghi'}
 241   Text.redraw_all(Editor_state)
 242   Editor_state.cursor1 = {line=1, pos=8}
 243   edit.draw(Editor_state)
 244   edit.run_after_keychord(Editor_state, 'M-right')
 245   check_eq(Editor_state.cursor1.line, 2, 'line')
 246   check_eq(Editor_state.cursor1.pos, 4, 'pos')
 247 end
 248
 249 function test_click_moves_cursor()
 250   App.screen.init{width=50, height=60}
 251   Editor_state = edit.initialize_test_state()
 252   Editor_state.lines = load_array{'abc', 'def', 'xyz'}
 253   Text.redraw_all(Editor_state)
 254   Editor_state.cursor1 = {line=1, pos=1}
 255   Editor_state.screen_top1 = {line=1, pos=1}
 256   Editor_state.screen_bottom1 = {}
 257   Editor_state.selection1 = {}
 258   edit.draw(Editor_state)  -- populate line_cache.starty for each line Editor_state.line_cache
 259   edit.run_after_mouse_release(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
 260   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
 261   check_eq(Editor_state.cursor1.pos, 2, 'cursor:pos')
 262   -- selection is empty to avoid perturbing future edits
 263   check_nil(Editor_state.selection1.line, 'selection:line')
 264   check_nil(Editor_state.selection1.pos, 'selection:pos')
 265 end
 266
 267 function test_click_to_left_of_line()
 268   -- display a line with the cursor in the middle
 269   App.screen.init{width=50, height=80}
 270   Editor_state = edit.initialize_test_state()
 271   Editor_state.lines = load_array{'abc'}
 272   Text.redraw_all(Editor_state)
 273   Editor_state.cursor1 = {line=1, pos=3}
 274   Editor_state.screen_top1 = {line=1, pos=1}
 275   Editor_state.screen_bottom1 = {}
 276   -- click to the left of the line
 277   edit.draw(Editor_state)
 278   edit.run_after_mouse_click(Editor_state, Editor_state.left-4,Editor_state.top+5, 1)
 279   -- cursor moves to start of line
 280   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
 281   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
 282   check_nil(Editor_state.selection1.line, 'selection is empty to avoid perturbing future edits')
 283 end
 284
 285 function test_click_takes_margins_into_account()
 286   -- display two lines with cursor on one of them
 287   App.screen.init{width=100, height=80}
 288   Editor_state = edit.initialize_test_state()
 289   Editor_state.left = 50  -- occupy only right side of screen
 290   Editor_state.lines = load_array{'abc', 'def'}
 291   Text.redraw_all(Editor_state)
 292   Editor_state.cursor1 = {line=2, pos=1}
 293   Editor_state.screen_top1 = {line=1, pos=1}
 294   Editor_state.screen_bottom1 = {}
 295   -- click on the other line
 296   edit.draw(Editor_state)
 297   edit.run_after_mouse_click(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
 298   -- cursor moves
 299   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
 300   check_eq(Editor_state.cursor1.pos, 2, 'cursor:pos')
 301   check_nil(Editor_state.selection1.line, 'selection is empty to avoid perturbing future edits')
 302 end
 303
 304 function test_click_on_empty_line()
 305   -- display two lines with the first one empty
 306   App.screen.init{width=50, height=80}
 307   Editor_state = edit.initialize_test_state()
 308   Editor_state.lines = load_array{'', 'def'}
 309   Text.redraw_all(Editor_state)
 310   Editor_state.cursor1 = {line=2, pos=1}
 311   Editor_state.screen_top1 = {line=1, pos=1}
 312   Editor_state.screen_bottom1 = {}
 313   -- click on the empty line
 314   edit.draw(Editor_state)
 315   edit.run_after_mouse_click(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
 316   -- cursor moves
 317   check_eq(Editor_state.cursor1.line, 1, 'cursor')
 318 end
 319
 320 function test_draw_text()
 321   App.screen.init{width=120, height=60}
 322   Editor_state = edit.initialize_test_state()
 323   Editor_state.lines = load_array{'abc', 'def', 'ghi'}
 324   Text.redraw_all(Editor_state)
 325   Editor_state.cursor1 = {line=1, pos=1}
 326   Editor_state.screen_top1 = {line=1, pos=1}
 327   Editor_state.screen_bottom1 = {}
 328   edit.draw(Editor_state)
 329   local y = Editor_state.top
 330   App.screen.check(y, 'abc', 'screen:1')
 331   y = y + Editor_state.line_height
 332   App.screen.check(y, 'def', 'screen:2')
 333   y = y + Editor_state.line_height
 334   App.screen.check(y, 'ghi', 'screen:3')
 335 end
 336
 337 function test_draw_wrapping_text()
 338   App.screen.init{width=50, height=60}
 339   Editor_state = edit.initialize_test_state()
 340   Editor_state.lines = load_array{'abc', 'defgh', 'xyz'}
 341   Text.redraw_all(Editor_state)
 342   Editor_state.cursor1 = {line=1, pos=1}
 343   Editor_state.screen_top1 = {line=1, pos=1}
 344   Editor_state.screen_bottom1 = {}
 345   edit.draw(Editor_state)
 346   local y = Editor_state.top
 347   App.screen.check(y, 'abc', 'screen:1')
 348   y = y + Editor_state.line_height
 349   App.screen.check(y, 'de', 'screen:2')
 350   y = y + Editor_state.line_height
 351   App.screen.check(y, 'fgh', 'screen:3')
 352 end
 353
 354 function test_draw_word_wrapping_text()
 355   App.screen.init{width=60, height=60}
 356   Editor_state = edit.initialize_test_state()
 357   Editor_state.lines = load_array{'abc def ghi', 'jkl'}
 358   Text.redraw_all(Editor_state)
 359   Editor_state.cursor1 = {line=1, pos=1}
 360   Editor_state.screen_top1 = {line=1, pos=1}
 361   Editor_state.screen_bottom1 = {}
 362   edit.draw(Editor_state)
 363   local y = Editor_state.top
 364   App.screen.check(y, 'abc ', 'screen:1')
 365   y = y + Editor_state.line_height
 366   App.screen.check(y, 'def ', 'screen:2')
 367   y = y + Editor_state.line_height
 368   App.screen.check(y, 'ghi', 'screen:3')
 369 end
 370
 371 function test_click_on_wrapping_line()
 372   -- display two lines with cursor on one of them
 373   App.screen.init{width=50, height=80}
 374   Editor_state = edit.initialize_test_state()
 375   Editor_state.lines = load_array{'abc def ghi jkl mno pqr stu'}
 376   Text.redraw_all(Editor_state)
 377   Editor_state.cursor1 = {line=1, pos=20}
 378   Editor_state.screen_top1 = {line=1, pos=1}
 379   Editor_state.screen_bottom1 = {}
 380   -- click on the other line
 381   edit.draw(Editor_state)
 382   edit.run_after_mouse_click(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
 383   -- cursor moves
 384   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
 385   check_eq(Editor_state.cursor1.pos, 2, 'cursor:pos')
 386   check_nil(Editor_state.selection1.line, 'selection is empty to avoid perturbing future edits')
 387 end
 388
 389 function test_click_on_wrapping_line_takes_margins_into_account()
 390   -- display two lines with cursor on one of them
 391   App.screen.init{width=100, height=80}
 392   Editor_state = edit.initialize_test_state()
 393   Editor_state.left = 50  -- occupy only right side of screen
 394   Editor_state.lines = load_array{'abc def ghi jkl mno pqr stu'}
 395   Text.redraw_all(Editor_state)
 396   Editor_state.cursor1 = {line=1, pos=20}
 397   Editor_state.screen_top1 = {line=1, pos=1}
 398   Editor_state.screen_bottom1 = {}
 399   -- click on the other line
 400   edit.draw(Editor_state)
 401   edit.run_after_mouse_click(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
 402   -- cursor moves
 403   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
 404   check_eq(Editor_state.cursor1.pos, 2, 'cursor:pos')
 405   check_nil(Editor_state.selection1.line, 'selection is empty to avoid perturbing future edits')
 406 end
 407
 408 function test_draw_text_wrapping_within_word()
 409   -- arrange a screen line that needs to be split within a word
 410   App.screen.init{width=60, height=60}
 411   Editor_state = edit.initialize_test_state()
 412   Editor_state.lines = load_array{'abcd e fghijk', 'xyz'}
 413   Text.redraw_all(Editor_state)
 414   Editor_state.cursor1 = {line=1, pos=1}
 415   Editor_state.screen_top1 = {line=1, pos=1}
 416   Editor_state.screen_bottom1 = {}
 417   edit.draw(Editor_state)
 418   local y = Editor_state.top
 419   App.screen.check(y, 'abcd ', 'screen:1')
 420   y = y + Editor_state.line_height
 421   App.screen.check(y, 'e fgh', 'screen:2')
 422   y = y + Editor_state.line_height
 423   App.screen.check(y, 'ijk', 'screen:3')
 424 end
 425
 426 function test_draw_wrapping_text_containing_non_ascii()
 427   -- draw a long line containing non-ASCII
 428   App.screen.init{width=60, height=60}
 429   Editor_state = edit.initialize_test_state()
 430   Editor_state.lines = load_array{'madam I’m adam', 'xyz'}  -- notice the non-ASCII apostrophe
 431   Text.redraw_all(Editor_state)
 432   Editor_state.cursor1 = {line=1, pos=1}
 433   Editor_state.screen_top1 = {line=1, pos=1}
 434   Editor_state.screen_bottom1 = {}
 435   edit.draw(Editor_state)
 436   local y = Editor_state.top
 437   App.screen.check(y, 'mad', 'screen:1')
 438   y = y + Editor_state.line_height
 439   App.screen.check(y, 'am I', 'screen:2')
 440   y = y + Editor_state.line_height
 441   App.screen.check(y, '’m a', 'screen:3')
 442 end
 443
 444 function test_click_on_wrapping_line()
 445   -- display a wrapping line
 446   App.screen.init{width=75, height=80}
 447   Editor_state = edit.initialize_test_state()
 448                                --  12345678901234
 449   Editor_state.lines = load_array{"madam I'm adam"}
 450   Text.redraw_all(Editor_state)
 451   Editor_state.cursor1 = {line=1, pos=1}
 452   Editor_state.screen_top1 = {line=1, pos=1}
 453   Editor_state.screen_bottom1 = {}
 454   edit.draw(Editor_state)
 455   local y = Editor_state.top
 456   App.screen.check(y, 'madam ', 'baseline/screen:1')
 457   y = y + Editor_state.line_height
 458   App.screen.check(y, "I'm ad", 'baseline/screen:2')
 459   y = y + Editor_state.line_height
 460   -- click past end of second screen line
 461   edit.run_after_mouse_click(Editor_state, App.screen.width-2,y-2, 1)
 462   -- cursor moves to end of screen line
 463   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
 464   check_eq(Editor_state.cursor1.pos, 12, 'cursor:pos')
 465 end
 466
 467 function test_click_on_wrapping_line_rendered_from_partway_at_top_of_screen()
 468   -- display a wrapping line from its second screen line
 469   App.screen.init{width=75, height=80}
 470   Editor_state = edit.initialize_test_state()
 471                                --  12345678901234
 472   Editor_state.lines = load_array{"madam I'm adam"}
 473   Text.redraw_all(Editor_state)
 474   Editor_state.cursor1 = {line=1, pos=8}
 475   Editor_state.screen_top1 = {line=1, pos=7}
 476   Editor_state.screen_bottom1 = {}
 477   edit.draw(Editor_state)
 478   local y = Editor_state.top
 479   App.screen.check(y, "I'm ad", 'baseline/screen:2')
 480   y = y + Editor_state.line_height
 481   -- click past end of second screen line
 482   edit.run_after_mouse_click(Editor_state, App.screen.width-2,y-2, 1)
 483   -- cursor moves to end of screen line
 484   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
 485   check_eq(Editor_state.cursor1.pos, 12, 'cursor:pos')
 486 end
 487
 488 function test_click_past_end_of_wrapping_line()
 489   -- display a wrapping line
 490   App.screen.init{width=75, height=80}
 491   Editor_state = edit.initialize_test_state()
 492                                --  12345678901234
 493   Editor_state.lines = load_array{"madam I'm adam"}
 494   Text.redraw_all(Editor_state)
 495   Editor_state.cursor1 = {line=1, pos=1}
 496   Editor_state.screen_top1 = {line=1, pos=1}
 497   Editor_state.screen_bottom1 = {}
 498   edit.draw(Editor_state)
 499   local y = Editor_state.top
 500   App.screen.check(y, 'madam ', 'baseline/screen:1')
 501   y = y + Editor_state.line_height
 502   App.screen.check(y, "I'm ad", 'baseline/screen:2')
 503   y = y + Editor_state.line_height
 504   App.screen.check(y, 'am', 'baseline/screen:3')
 505   y = y + Editor_state.line_height
 506   -- click past the end of it
 507   edit.run_after_mouse_click(Editor_state, App.screen.width-2,y-2, 1)
 508   -- cursor moves to end of line
 509   check_eq(Editor_state.cursor1.pos, 15, 'cursor')  -- one more than the number of UTF-8 code-points
 510 end
 511
 512 function test_click_past_end_of_wrapping_line_containing_non_ascii()
 513   -- display a wrapping line containing non-ASCII
 514   App.screen.init{width=75, height=80}
 515   Editor_state = edit.initialize_test_state()
 516                                --  12345678901234
 517   Editor_state.lines = load_array{'madam I’m adam'}  -- notice the non-ASCII apostrophe
 518   Text.redraw_all(Editor_state)
 519   Editor_state.cursor1 = {line=1, pos=1}
 520   Editor_state.screen_top1 = {line=1, pos=1}
 521   Editor_state.screen_bottom1 = {}
 522   edit.draw(Editor_state)
 523   local y = Editor_state.top
 524   App.screen.check(y, 'madam ', 'baseline/screen:1')
 525   y = y + Editor_state.line_height
 526   App.screen.check(y, 'I’m ad', 'baseline/screen:2')
 527   y = y + Editor_state.line_height
 528   App.screen.check(y, 'am', 'baseline/screen:3')
 529   y = y + Editor_state.line_height
 530   -- click past the end of it
 531   edit.run_after_mouse_click(Editor_state, App.screen.width-2,y-2, 1)
 532   -- cursor moves to end of line
 533   check_eq(Editor_state.cursor1.pos, 15, 'cursor')  -- one more than the number of UTF-8 code-points
 534 end
 535
 536 function test_click_past_end_of_word_wrapping_line()
 537   -- display a long line wrapping at a word boundary on a screen of more realistic length
 538   App.screen.init{width=160, height=80}
 539   Editor_state = edit.initialize_test_state()
 540                                 -- 0        1         2
 541                                 -- 123456789012345678901
 542   Editor_state.lines = load_array{'the quick brown fox jumped over the lazy dog'}
 543   Text.redraw_all(Editor_state)
 544   Editor_state.cursor1 = {line=1, pos=1}
 545   Editor_state.screen_top1 = {line=1, pos=1}
 546   Editor_state.screen_bottom1 = {}
 547   edit.draw(Editor_state)
 548   local y = Editor_state.top
 549   App.screen.check(y, 'the quick brown fox ', 'baseline/screen:1')
 550   y = y + Editor_state.line_height
 551   -- click past the end of the screen line
 552   edit.run_after_mouse_click(Editor_state, App.screen.width-2,y-2, 1)
 553   -- cursor moves to end of screen line
 554   check_eq(Editor_state.cursor1.pos, 20, 'cursor')
 555 end
 556
 557 function test_select_text()
 558   -- display a line of text
 559   App.screen.init{width=75, height=80}
 560   Editor_state = edit.initialize_test_state()
 561   Editor_state.lines = load_array{'abc def'}
 562   Text.redraw_all(Editor_state)
 563   Editor_state.cursor1 = {line=1, pos=1}
 564   Editor_state.screen_top1 = {line=1, pos=1}
 565   Editor_state.screen_bottom1 = {}
 566   edit.draw(Editor_state)
 567   -- select a letter
 568   App.fake_key_press('lshift')
 569   edit.run_after_keychord(Editor_state, 'S-right')
 570   App.fake_key_release('lshift')
 571   edit.key_release(Editor_state, 'lshift')
 572   -- selection persists even after shift is released
 573   check_eq(Editor_state.selection1.line, 1, 'selection:line')
 574   check_eq(Editor_state.selection1.pos, 1, 'selection:pos')
 575   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
 576   check_eq(Editor_state.cursor1.pos, 2, 'cursor:pos')
 577 end
 578
 579 function test_cursor_movement_without_shift_resets_selection()
 580   -- display a line of text with some part selected
 581   App.screen.init{width=75, height=80}
 582   Editor_state = edit.initialize_test_state()
 583   Editor_state.lines = load_array{'abc'}
 584   Text.redraw_all(Editor_state)
 585   Editor_state.cursor1 = {line=1, pos=1}
 586   Editor_state.selection1 = {line=1, pos=2}
 587   Editor_state.screen_top1 = {line=1, pos=1}
 588   Editor_state.screen_bottom1 = {}
 589   edit.draw(Editor_state)
 590   -- press an arrow key without shift
 591   edit.run_after_keychord(Editor_state, 'right')
 592   -- no change to data, selection is reset
 593   check_nil(Editor_state.selection1.line, 'check')
 594   check_eq(Editor_state.lines[1].data, 'abc', 'data')
 595 end
 596
 597 function test_edit_deletes_selection()
 598   -- display a line of text with some part selected
 599   App.screen.init{width=75, height=80}
 600   Editor_state = edit.initialize_test_state()
 601   Editor_state.lines = load_array{'abc'}
 602   Text.redraw_all(Editor_state)
 603   Editor_state.cursor1 = {line=1, pos=1}
 604   Editor_state.selection1 = {line=1, pos=2}
 605   Editor_state.screen_top1 = {line=1, pos=1}
 606   Editor_state.screen_bottom1 = {}
 607   edit.draw(Editor_state)
 608   -- press a key
 609   edit.run_after_text_input(Editor_state, 'x')
 610   -- selected text is deleted and replaced with the key
 611   check_eq(Editor_state.lines[1].data, 'xbc', 'check')
 612 end
 613
 614 function test_edit_with_shift_key_deletes_selection()
 615   -- display a line of text with some part selected
 616   App.screen.init{width=75, height=80}
 617   Editor_state = edit.initialize_test_state()
 618   Editor_state.lines = load_array{'abc'}
 619   Text.redraw_all(Editor_state)
 620   Editor_state.cursor1 = {line=1, pos=1}
 621   Editor_state.selection1 = {line=1, pos=2}
 622   Editor_state.screen_top1 = {line=1, pos=1}
 623   Editor_state.screen_bottom1 = {}
 624   edit.draw(Editor_state)
 625   -- mimic precise keypresses for a capital letter
 626   App.fake_key_press('lshift')
 627   edit.keychord_press(Editor_state, 'd', 'd')
 628   edit.text_input(Editor_state, 'D')
 629   edit.key_release(Editor_state, 'd')
 630   App.fake_key_release('lshift')
 631   -- selected text is deleted and replaced with the key
 632   check_nil(Editor_state.selection1.line, 'check')
 633   check_eq(Editor_state.lines[1].data, 'Dbc', 'data')
 634 end
 635
 636 function test_copy_does_not_reset_selection()
 637   -- display a line of text with a selection
 638   App.screen.init{width=75, height=80}
 639   Editor_state = edit.initialize_test_state()
 640   Editor_state.lines = load_array{'abc'}
 641   Text.redraw_all(Editor_state)
 642   Editor_state.cursor1 = {line=1, pos=1}
 643   Editor_state.selection1 = {line=1, pos=2}
 644   Editor_state.screen_top1 = {line=1, pos=1}
 645   Editor_state.screen_bottom1 = {}
 646   edit.draw(Editor_state)
 647   -- copy selection
 648   edit.run_after_keychord(Editor_state, 'C-c')
 649   check_eq(App.clipboard, 'a', 'clipboard')
 650   -- selection is reset since shift key is not pressed
 651   check(Editor_state.selection1.line, 'check')
 652 end
 653
 654 function test_cut()
 655   -- display a line of text with some part selected
 656   App.screen.init{width=75, height=80}
 657   Editor_state = edit.initialize_test_state()
 658   Editor_state.lines = load_array{'abc'}
 659   Text.redraw_all(Editor_state)
 660   Editor_state.cursor1 = {line=1, pos=1}
 661   Editor_state.selection1 = {line=1, pos=2}
 662   Editor_state.screen_top1 = {line=1, pos=1}
 663   Editor_state.screen_bottom1 = {}
 664   edit.draw(Editor_state)
 665   -- press a key
 666   edit.run_after_keychord(Editor_state, 'C-x')
 667   check_eq(App.clipboard, 'a', 'clipboard')
 668   -- selected text is deleted
 669   check_eq(Editor_state.lines[1].data, 'bc', 'data')
 670 end
 671
 672 function test_paste_replaces_selection()
 673   -- display a line of text with a selection
 674   App.screen.init{width=75, height=80}
 675   Editor_state = edit.initialize_test_state()
 676   Editor_state.lines = load_array{'abc', 'def'}
 677   Text.redraw_all(Editor_state)
 678   Editor_state.cursor1 = {line=2, pos=1}
 679   Editor_state.selection1 = {line=1, pos=1}
 680   Editor_state.screen_top1 = {line=1, pos=1}
 681   Editor_state.screen_bottom1 = {}
 682   edit.draw(Editor_state)
 683   -- set clipboard
 684   App.clipboard = 'xyz'
 685   -- paste selection
 686   edit.run_after_keychord(Editor_state, 'C-v')
 687   -- selection is reset since shift key is not pressed
 688   -- selection includes the newline, so it's also deleted
 689   check_eq(Editor_state.lines[1].data, 'xyzdef', 'check')
 690 end
 691
 692 function test_deleting_selection_may_scroll()
 693   -- display lines 2/3/4
 694   App.screen.init{width=120, height=60}
 695   Editor_state = edit.initialize_test_state()
 696   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
 697   Text.redraw_all(Editor_state)
 698   Editor_state.cursor1 = {line=3, pos=2}
 699   Editor_state.screen_top1 = {line=2, pos=1}
 700   Editor_state.screen_bottom1 = {}
 701   edit.draw(Editor_state)
 702   local y = Editor_state.top
 703   App.screen.check(y, 'def', 'baseline/screen:1')
 704   y = y + Editor_state.line_height
 705   App.screen.check(y, 'ghi', 'baseline/screen:2')
 706   y = y + Editor_state.line_height
 707   App.screen.check(y, 'jkl', 'baseline/screen:3')
 708   -- set up a selection starting above the currently displayed page
 709   Editor_state.selection1 = {line=1, pos=2}
 710   -- delete selection
 711   edit.run_after_keychord(Editor_state, 'backspace')
 712   -- page scrolls up
 713   check_eq(Editor_state.screen_top1.line, 1, 'check')
 714   check_eq(Editor_state.lines[1].data, 'ahi', 'data')
 715 end
 716
 717 function test_edit_wrapping_text()
 718   App.screen.init{width=50, height=60}
 719   Editor_state = edit.initialize_test_state()
 720   Editor_state.lines = load_array{'abc', 'def', 'xyz'}
 721   Text.redraw_all(Editor_state)
 722   Editor_state.cursor1 = {line=2, pos=4}
 723   Editor_state.screen_top1 = {line=1, pos=1}
 724   Editor_state.screen_bottom1 = {}
 725   edit.draw(Editor_state)
 726   edit.run_after_text_input(Editor_state, 'g')
 727   local y = Editor_state.top
 728   App.screen.check(y, 'abc', 'screen:1')
 729   y = y + Editor_state.line_height
 730   App.screen.check(y, 'de', 'screen:2')
 731   y = y + Editor_state.line_height
 732   App.screen.check(y, 'fg', 'screen:3')
 733 end
 734
 735 function test_insert_newline()
 736   -- display a few lines
 737   App.screen.init{width=Editor_state.left+30, height=60}
 738   Editor_state = edit.initialize_test_state()
 739   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
 740   Text.redraw_all(Editor_state)
 741   Editor_state.cursor1 = {line=1, pos=2}
 742   Editor_state.screen_top1 = {line=1, pos=1}
 743   Editor_state.screen_bottom1 = {}
 744   edit.draw(Editor_state)
 745   local y = Editor_state.top
 746   App.screen.check(y, 'abc', 'baseline/screen:1')
 747   y = y + Editor_state.line_height
 748   App.screen.check(y, 'def', 'baseline/screen:2')
 749   y = y + Editor_state.line_height
 750   App.screen.check(y, 'ghi', 'baseline/screen:3')
 751   -- hitting the enter key splits the line
 752   edit.run_after_keychord(Editor_state, 'return')
 753   check_eq(Editor_state.screen_top1.line, 1, 'screen_top')
 754   check_eq(Editor_state.cursor1.line, 2, 'cursor:line')
 755   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
 756   y = Editor_state.top
 757   App.screen.check(y, 'a', 'screen:1')
 758   y = y + Editor_state.line_height
 759   App.screen.check(y, 'bc', 'screen:2')
 760   y = y + Editor_state.line_height
 761   App.screen.check(y, 'def', 'screen:3')
 762 end
 763
 764 function test_insert_newline_at_start_of_line()
 765   -- display a line
 766   App.screen.init{width=Editor_state.left+30, height=60}
 767   Editor_state = edit.initialize_test_state()
 768   Editor_state.lines = load_array{'abc'}
 769   Text.redraw_all(Editor_state)
 770   Editor_state.cursor1 = {line=1, pos=1}
 771   Editor_state.screen_top1 = {line=1, pos=1}
 772   Editor_state.screen_bottom1 = {}
 773   -- hitting the enter key splits the line
 774   edit.run_after_keychord(Editor_state, 'return')
 775   check_eq(Editor_state.cursor1.line, 2, 'cursor:line')
 776   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
 777   check_eq(Editor_state.lines[1].data, '', 'data:1')
 778   check_eq(Editor_state.lines[2].data, 'abc', 'data:2')
 779 end
 780
 781 function test_insert_from_clipboard()
 782   -- display a few lines
 783   App.screen.init{width=Editor_state.left+30, height=60}
 784   Editor_state = edit.initialize_test_state()
 785   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
 786   Text.redraw_all(Editor_state)
 787   Editor_state.cursor1 = {line=1, pos=2}
 788   Editor_state.screen_top1 = {line=1, pos=1}
 789   Editor_state.screen_bottom1 = {}
 790   edit.draw(Editor_state)
 791   local y = Editor_state.top
 792   App.screen.check(y, 'abc', 'baseline/screen:1')
 793   y = y + Editor_state.line_height
 794   App.screen.check(y, 'def', 'baseline/screen:2')
 795   y = y + Editor_state.line_height
 796   App.screen.check(y, 'ghi', 'baseline/screen:3')
 797   -- paste some text including a newline, check that new line is created
 798   App.clipboard = 'xy\nz'
 799   edit.run_after_keychord(Editor_state, 'C-v')
 800   check_eq(Editor_state.screen_top1.line, 1, 'screen_top')
 801   check_eq(Editor_state.cursor1.line, 2, 'cursor:line')
 802   check_eq(Editor_state.cursor1.pos, 2, 'cursor:pos')
 803   y = Editor_state.top
 804   App.screen.check(y, 'axy', 'screen:1')
 805   y = y + Editor_state.line_height
 806   App.screen.check(y, 'zbc', 'screen:2')
 807   y = y + Editor_state.line_height
 808   App.screen.check(y, 'def', 'screen:3')
 809 end
 810
 811 function test_select_text_using_mouse()
 812   App.screen.init{width=50, height=60}
 813   Editor_state = edit.initialize_test_state()
 814   Editor_state.lines = load_array{'abc', 'def', 'xyz'}
 815   Text.redraw_all(Editor_state)
 816   Editor_state.cursor1 = {line=1, pos=1}
 817   Editor_state.screen_top1 = {line=1, pos=1}
 818   Editor_state.screen_bottom1 = {}
 819   Editor_state.selection1 = {}
 820   edit.draw(Editor_state)  -- populate line_cache.starty for each line Editor_state.line_cache
 821   -- press and hold on first location
 822   edit.run_after_mouse_press(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
 823   -- drag and release somewhere else
 824   edit.run_after_mouse_release(Editor_state, Editor_state.left+20,Editor_state.top+Editor_state.line_height+5, 1)
 825   check_eq(Editor_state.selection1.line, 1, 'selection:line')
 826   check_eq(Editor_state.selection1.pos, 2, 'selection:pos')
 827   check_eq(Editor_state.cursor1.line, 2, 'cursor:line')
 828   check_eq(Editor_state.cursor1.pos, 4, 'cursor:pos')
 829 end
 830
 831 function test_select_text_using_mouse_and_shift()
 832   App.screen.init{width=50, height=60}
 833   Editor_state = edit.initialize_test_state()
 834   Editor_state.lines = load_array{'abc', 'def', 'xyz'}
 835   Text.redraw_all(Editor_state)
 836   Editor_state.cursor1 = {line=1, pos=1}
 837   Editor_state.screen_top1 = {line=1, pos=1}
 838   Editor_state.screen_bottom1 = {}
 839   Editor_state.selection1 = {}
 840   edit.draw(Editor_state)  -- populate line_cache.starty for each line Editor_state.line_cache
 841   -- click on first location
 842   edit.run_after_mouse_press(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
 843   edit.run_after_mouse_release(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
 844   -- hold down shift and click somewhere else
 845   App.fake_key_press('lshift')
 846   edit.run_after_mouse_press(Editor_state, Editor_state.left+20,Editor_state.top+5, 1)
 847   edit.run_after_mouse_release(Editor_state, Editor_state.left+20,Editor_state.top+Editor_state.line_height+5, 1)
 848   App.fake_key_release('lshift')
 849   check_eq(Editor_state.selection1.line, 1, 'selection:line')
 850   check_eq(Editor_state.selection1.pos, 2, 'selection:pos')
 851   check_eq(Editor_state.cursor1.line, 2, 'cursor:line')
 852   check_eq(Editor_state.cursor1.pos, 4, 'cursor:pos')
 853 end
 854
 855 function test_select_text_repeatedly_using_mouse_and_shift()
 856   App.screen.init{width=50, height=60}
 857   Editor_state = edit.initialize_test_state()
 858   Editor_state.lines = load_array{'abc', 'def', 'xyz'}
 859   Text.redraw_all(Editor_state)
 860   Text.redraw_all(Editor_state)
 861   Editor_state.cursor1 = {line=1, pos=1}
 862   Editor_state.screen_top1 = {line=1, pos=1}
 863   Editor_state.screen_bottom1 = {}
 864   Editor_state.selection1 = {}
 865   edit.draw(Editor_state)  -- populate line_cache.starty for each line Editor_state.line_cache
 866   -- click on first location
 867   edit.run_after_mouse_press(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
 868   edit.run_after_mouse_release(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
 869   -- hold down shift and click on a second location
 870   App.fake_key_press('lshift')
 871   edit.run_after_mouse_press(Editor_state, Editor_state.left+20,Editor_state.top+5, 1)
 872   edit.run_after_mouse_release(Editor_state, Editor_state.left+20,Editor_state.top+Editor_state.line_height+5, 1)
 873   -- hold down shift and click at a third location
 874   App.fake_key_press('lshift')
 875   edit.run_after_mouse_press(Editor_state, Editor_state.left+20,Editor_state.top+5, 1)
 876   edit.run_after_mouse_release(Editor_state, Editor_state.left+8,Editor_state.top+Editor_state.line_height+5, 1)
 877   App.fake_key_release('lshift')
 878   -- selection is between first and third location. forget the second location, not the first.
 879   check_eq(Editor_state.selection1.line, 1, 'selection:line')
 880   check_eq(Editor_state.selection1.pos, 2, 'selection:pos')
 881   check_eq(Editor_state.cursor1.line, 2, 'cursor:line')
 882   check_eq(Editor_state.cursor1.pos, 2, 'cursor:pos')
 883 end
 884
 885 function test_cut_without_selection()
 886   -- display a few lines
 887   App.screen.init{width=Editor_state.left+30, height=60}
 888   Editor_state = edit.initialize_test_state()
 889   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
 890   Text.redraw_all(Editor_state)
 891   Editor_state.cursor1 = {line=1, pos=2}
 892   Editor_state.screen_top1 = {line=1, pos=1}
 893   Editor_state.screen_bottom1 = {}
 894   Editor_state.selection1 = {}
 895   edit.draw(Editor_state)
 896   -- try to cut without selecting text
 897   edit.run_after_keychord(Editor_state, 'C-x')
 898   -- no crash
 899   check_nil(Editor_state.selection1.line, 'check')
 900 end
 901
 902 function test_pagedown()
 903   App.screen.init{width=120, height=45}
 904   Editor_state = edit.initialize_test_state()
 905   Editor_state.lines = load_array{'abc', 'def', 'ghi'}
 906   Text.redraw_all(Editor_state)
 907   Editor_state.cursor1 = {line=1, pos=1}
 908   Editor_state.screen_top1 = {line=1, pos=1}
 909   Editor_state.screen_bottom1 = {}
 910   -- initially the first two lines are displayed
 911   edit.draw(Editor_state)
 912   local y = Editor_state.top
 913   App.screen.check(y, 'abc', 'baseline/screen:1')
 914   y = y + Editor_state.line_height
 915   App.screen.check(y, 'def', 'baseline/screen:2')
 916   -- after pagedown the bottom line becomes the top
 917   edit.run_after_keychord(Editor_state, 'pagedown')
 918   check_eq(Editor_state.screen_top1.line, 2, 'screen_top')
 919   check_eq(Editor_state.cursor1.line, 2, 'cursor')
 920   y = Editor_state.top
 921   App.screen.check(y, 'def', 'screen:1')
 922   y = y + Editor_state.line_height
 923   App.screen.check(y, 'ghi', 'screen:2')
 924 end
 925
 926 function test_pagedown_skips_drawings()
 927   -- some lines of text with a drawing intermixed
 928   local drawing_width = 50
 929   App.screen.init{width=Editor_state.left+drawing_width, height=80}
 930   Editor_state = edit.initialize_test_state()
 931   Editor_state.lines = load_array{'abc',               -- height 15
 932                                   '```lines', '```',   -- height 25
 933                                   'def',               -- height 15
 934                                   'ghi'}               -- height 15
 935   Text.redraw_all(Editor_state)
 936   check_eq(Editor_state.lines[2].mode, 'drawing', 'baseline/lines')
 937   Editor_state.cursor1 = {line=1, pos=1}
 938   Editor_state.screen_top1 = {line=1, pos=1}
 939   Editor_state.screen_bottom1 = {}
 940   local drawing_height = Drawing_padding_height + drawing_width/2  -- default
 941   -- initially the screen displays the first line and the drawing
 942   -- 15px margin + 15px line1 + 10px margin + 25px drawing + 10px margin = 75px < screen height 80px
 943   edit.draw(Editor_state)
 944   local y = Editor_state.top
 945   App.screen.check(y, 'abc', 'baseline/screen:1')
 946   -- after pagedown the screen draws the drawing up top
 947   -- 15px margin + 10px margin + 25px drawing + 10px margin + 15px line3 = 75px < screen height 80px
 948   edit.run_after_keychord(Editor_state, 'pagedown')
 949   check_eq(Editor_state.screen_top1.line, 2, 'screen_top')
 950   check_eq(Editor_state.cursor1.line, 3, 'cursor')
 951   y = Editor_state.top + drawing_height
 952   App.screen.check(y, 'def', 'screen:1')
 953 end
 954
 955 function test_pagedown_often_shows_start_of_wrapping_line()
 956   -- draw a few lines ending in part of a wrapping line
 957   App.screen.init{width=50, height=60}
 958   Editor_state = edit.initialize_test_state()
 959   Editor_state.lines = load_array{'abc', 'def ghi jkl', 'mno'}
 960   Text.redraw_all(Editor_state)
 961   Editor_state.cursor1 = {line=1, pos=1}
 962   Editor_state.screen_top1 = {line=1, pos=1}
 963   Editor_state.screen_bottom1 = {}
 964   edit.draw(Editor_state)
 965   local y = Editor_state.top
 966   App.screen.check(y, 'abc', 'baseline/screen:1')
 967   y = y + Editor_state.line_height
 968   App.screen.check(y, 'def ', 'baseline/screen:2')
 969   y = y + Editor_state.line_height
 970   App.screen.check(y, 'ghi ', 'baseline/screen:3')
 971   -- after pagedown we start drawing from the bottom _line_ (multiple screen lines)
 972   edit.run_after_keychord(Editor_state, 'pagedown')
 973   check_eq(Editor_state.screen_top1.line, 2, 'screen_top:line')
 974   check_eq(Editor_state.screen_top1.pos, 1, 'screen_top:pos')
 975   check_eq(Editor_state.cursor1.line, 2, 'cursor:line')
 976   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
 977   y = Editor_state.top
 978   App.screen.check(y, 'def ', 'screen:1')
 979   y = y + Editor_state.line_height
 980   App.screen.check(y, 'ghi ', 'screen:2')
 981   y = y + Editor_state.line_height
 982   App.screen.check(y, 'jkl', 'screen:3')
 983 end
 984
 985 function test_pagedown_can_start_from_middle_of_long_wrapping_line()
 986   -- draw a few lines starting from a very long wrapping line
 987   App.screen.init{width=Editor_state.left+30, height=60}
 988   Editor_state = edit.initialize_test_state()
 989   Editor_state.lines = load_array{'abc def ghi jkl mno pqr stu vwx yza bcd efg hij', 'XYZ'}
 990   Text.redraw_all(Editor_state)
 991   Editor_state.cursor1 = {line=1, pos=2}
 992   Editor_state.screen_top1 = {line=1, pos=1}
 993   Editor_state.screen_bottom1 = {}
 994   edit.draw(Editor_state)
 995   local y = Editor_state.top
 996   App.screen.check(y, 'abc ', 'baseline/screen:1')
 997   y = y + Editor_state.line_height
 998   App.screen.check(y, 'def ', 'baseline/screen:2')
 999   y = y + Editor_state.line_height
1000   App.screen.check(y, 'ghi ', 'baseline/screen:3')
1001   -- after pagedown we scroll down the very long wrapping line
1002   edit.run_after_keychord(Editor_state, 'pagedown')
1003   check_eq(Editor_state.screen_top1.line, 1, 'screen_top:line')
1004   check_eq(Editor_state.screen_top1.pos, 9, 'screen_top:pos')
1005   y = Editor_state.top
1006   App.screen.check(y, 'ghi ', 'screen:1')
1007   y = y + Editor_state.line_height
1008   App.screen.check(y, 'jkl ', 'screen:2')
1009   y = y + Editor_state.line_height
1010   App.screen.check(y, 'mno ', 'screen:3')
1011 end
1012
1013 function test_pagedown_never_moves_up()
1014   -- draw the final screen line of a wrapping line
1015   App.screen.init{width=Editor_state.left+30, height=60}
1016   Editor_state = edit.initialize_test_state()
1017   Editor_state.lines = load_array{'abc def ghi'}
1018   Text.redraw_all(Editor_state)
1019   Editor_state.cursor1 = {line=1, pos=9}
1020   Editor_state.screen_top1 = {line=1, pos=9}
1021   Editor_state.screen_bottom1 = {}
1022   edit.draw(Editor_state)
1023   -- pagedown makes no change
1024   edit.run_after_keychord(Editor_state, 'pagedown')
1025   check_eq(Editor_state.screen_top1.line, 1, 'screen_top:line')
1026   check_eq(Editor_state.screen_top1.pos, 9, 'screen_top:pos')
1027 end
1028
1029 function test_down_arrow_moves_cursor()
1030   App.screen.init{width=120, height=60}
1031   Editor_state = edit.initialize_test_state()
1032   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
1033   Text.redraw_all(Editor_state)
1034   Editor_state.cursor1 = {line=1, pos=1}
1035   Editor_state.screen_top1 = {line=1, pos=1}
1036   Editor_state.screen_bottom1 = {}
1037   -- initially the first three lines are displayed
1038   edit.draw(Editor_state)
1039   local y = Editor_state.top
1040   App.screen.check(y, 'abc', 'baseline/screen:1')
1041   y = y + Editor_state.line_height
1042   App.screen.check(y, 'def', 'baseline/screen:2')
1043   y = y + Editor_state.line_height
1044   App.screen.check(y, 'ghi', 'baseline/screen:3')
1045   -- after hitting the down arrow, the cursor moves down by 1 line
1046   edit.run_after_keychord(Editor_state, 'down')
1047   check_eq(Editor_state.screen_top1.line, 1, 'screen_top')
1048   check_eq(Editor_state.cursor1.line, 2, 'cursor')
1049   -- the screen is unchanged
1050   y = Editor_state.top
1051   App.screen.check(y, 'abc', 'screen:1')
1052   y = y + Editor_state.line_height
1053   App.screen.check(y, 'def', 'screen:2')
1054   y = y + Editor_state.line_height
1055   App.screen.check(y, 'ghi', 'screen:3')
1056 end
1057
1058 function test_down_arrow_scrolls_down_by_one_line()
1059   -- display the first three lines with the cursor on the bottom line
1060   App.screen.init{width=120, height=60}
1061   Editor_state = edit.initialize_test_state()
1062   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
1063   Text.redraw_all(Editor_state)
1064   Editor_state.cursor1 = {line=3, pos=1}
1065   Editor_state.screen_top1 = {line=1, pos=1}
1066   Editor_state.screen_bottom1 = {}
1067   edit.draw(Editor_state)
1068   local y = Editor_state.top
1069   App.screen.check(y, 'abc', 'baseline/screen:1')
1070   y = y + Editor_state.line_height
1071   App.screen.check(y, 'def', 'baseline/screen:2')
1072   y = y + Editor_state.line_height
1073   App.screen.check(y, 'ghi', 'baseline/screen:3')
1074   -- after hitting the down arrow the screen scrolls down by one line
1075   edit.run_after_keychord(Editor_state, 'down')
1076   check_eq(Editor_state.screen_top1.line, 2, 'screen_top')
1077   check_eq(Editor_state.cursor1.line, 4, 'cursor')
1078   y = Editor_state.top
1079   App.screen.check(y, 'def', 'screen:1')
1080   y = y + Editor_state.line_height
1081   App.screen.check(y, 'ghi', 'screen:2')
1082   y = y + Editor_state.line_height
1083   App.screen.check(y, 'jkl', 'screen:3')
1084 end
1085
1086 function test_down_arrow_scrolls_down_by_one_screen_line()
1087   -- display the first three lines with the cursor on the bottom line
1088   App.screen.init{width=Editor_state.left+30, height=60}
1089   Editor_state = edit.initialize_test_state()
1090   Editor_state.lines = load_array{'abc', 'def', 'ghi jkl', 'mno'}
1091   Text.redraw_all(Editor_state)
1092   Editor_state.cursor1 = {line=3, pos=1}
1093   Editor_state.screen_top1 = {line=1, pos=1}
1094   Editor_state.screen_bottom1 = {}
1095   edit.draw(Editor_state)
1096   local y = Editor_state.top
1097   App.screen.check(y, 'abc', 'baseline/screen:1')
1098   y = y + Editor_state.line_height
1099   App.screen.check(y, 'def', 'baseline/screen:2')
1100   y = y + Editor_state.line_height
1101   App.screen.check(y, 'ghi ', 'baseline/screen:3')  -- line wrapping includes trailing whitespace
1102   -- after hitting the down arrow the screen scrolls down by one line
1103   edit.run_after_keychord(Editor_state, 'down')
1104   check_eq(Editor_state.screen_top1.line, 2, 'screen_top')
1105   check_eq(Editor_state.cursor1.line, 3, 'cursor:line')
1106   check_eq(Editor_state.cursor1.pos, 5, 'cursor:pos')
1107   y = Editor_state.top
1108   App.screen.check(y, 'def', 'screen:1')
1109   y = y + Editor_state.line_height
1110   App.screen.check(y, 'ghi ', 'screen:2')
1111   y = y + Editor_state.line_height
1112   App.screen.check(y, 'jkl', 'screen:3')
1113 end
1114
1115 function test_down_arrow_scrolls_down_by_one_screen_line_after_splitting_within_word()
1116   -- display the first three lines with the cursor on the bottom line
1117   App.screen.init{width=Editor_state.left+30, height=60}
1118   Editor_state = edit.initialize_test_state()
1119   Editor_state.lines = load_array{'abc', 'def', 'ghijkl', 'mno'}
1120   Text.redraw_all(Editor_state)
1121   Editor_state.cursor1 = {line=3, pos=1}
1122   Editor_state.screen_top1 = {line=1, pos=1}
1123   Editor_state.screen_bottom1 = {}
1124   edit.draw(Editor_state)
1125   local y = Editor_state.top
1126   App.screen.check(y, 'abc', 'baseline/screen:1')
1127   y = y + Editor_state.line_height
1128   App.screen.check(y, 'def', 'baseline/screen:2')
1129   y = y + Editor_state.line_height
1130   App.screen.check(y, 'ghij', 'baseline/screen:3')
1131   -- after hitting the down arrow the screen scrolls down by one line
1132   edit.run_after_keychord(Editor_state, 'down')
1133   check_eq(Editor_state.screen_top1.line, 2, 'screen_top')
1134   check_eq(Editor_state.cursor1.line, 3, 'cursor:line')
1135   check_eq(Editor_state.cursor1.pos, 5, 'cursor:pos')
1136   y = Editor_state.top
1137   App.screen.check(y, 'def', 'screen:1')
1138   y = y + Editor_state.line_height
1139   App.screen.check(y, 'ghij', 'screen:2')
1140   y = y + Editor_state.line_height
1141   App.screen.check(y, 'kl', 'screen:3')
1142 end
1143
1144 function test_pagedown_followed_by_down_arrow_does_not_scroll_screen_up()
1145   App.screen.init{width=Editor_state.left+30, height=60}
1146   Editor_state = edit.initialize_test_state()
1147   Editor_state.lines = load_array{'abc', 'def', 'ghijkl', 'mno'}
1148   Text.redraw_all(Editor_state)
1149   Editor_state.cursor1 = {line=3, pos=1}
1150   Editor_state.screen_top1 = {line=1, pos=1}
1151   Editor_state.screen_bottom1 = {}
1152   edit.draw(Editor_state)
1153   local y = Editor_state.top
1154   App.screen.check(y, 'abc', 'baseline/screen:1')
1155   y = y + Editor_state.line_height
1156   App.screen.check(y, 'def', 'baseline/screen:2')
1157   y = y + Editor_state.line_height
1158   App.screen.check(y, 'ghij', 'baseline/screen:3')
1159   -- after hitting pagedown the screen scrolls down to start of a long line
1160   edit.run_after_keychord(Editor_state, 'pagedown')
1161   check_eq(Editor_state.screen_top1.line, 3, 'baseline2/screen_top')
1162   check_eq(Editor_state.cursor1.line, 3, 'baseline2/cursor:line')
1163   check_eq(Editor_state.cursor1.pos, 1, 'baseline2/cursor:pos')
1164   -- after hitting down arrow the screen doesn't scroll down further, and certainly doesn't scroll up
1165   edit.run_after_keychord(Editor_state, 'down')
1166   check_eq(Editor_state.screen_top1.line, 3, 'screen_top')
1167   check_eq(Editor_state.cursor1.line, 3, 'cursor:line')
1168   check_eq(Editor_state.cursor1.pos, 5, 'cursor:pos')
1169   y = Editor_state.top
1170   App.screen.check(y, 'ghij', 'screen:1')
1171   y = y + Editor_state.line_height
1172   App.screen.check(y, 'kl', 'screen:2')
1173   y = y + Editor_state.line_height
1174   App.screen.check(y, 'mno', 'screen:3')
1175 end
1176
1177 function test_up_arrow_moves_cursor()
1178   -- display the first 3 lines with the cursor on the bottom line
1179   App.screen.init{width=120, height=60}
1180   Editor_state = edit.initialize_test_state()
1181   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
1182   Text.redraw_all(Editor_state)
1183   Editor_state.cursor1 = {line=3, pos=1}
1184   Editor_state.screen_top1 = {line=1, pos=1}
1185   Editor_state.screen_bottom1 = {}
1186   edit.draw(Editor_state)
1187   local y = Editor_state.top
1188   App.screen.check(y, 'abc', 'baseline/screen:1')
1189   y = y + Editor_state.line_height
1190   App.screen.check(y, 'def', 'baseline/screen:2')
1191   y = y + Editor_state.line_height
1192   App.screen.check(y, 'ghi', 'baseline/screen:3')
1193   -- after hitting the up arrow the cursor moves up by 1 line
1194   edit.run_after_keychord(Editor_state, 'up')
1195   check_eq(Editor_state.screen_top1.line, 1, 'screen_top')
1196   check_eq(Editor_state.cursor1.line, 2, 'cursor')
1197   -- the screen is unchanged
1198   y = Editor_state.top
1199   App.screen.check(y, 'abc', 'screen:1')
1200   y = y + Editor_state.line_height
1201   App.screen.check(y, 'def', 'screen:2')
1202   y = y + Editor_state.line_height
1203   App.screen.check(y, 'ghi', 'screen:3')
1204 end
1205
1206 function test_up_arrow_scrolls_up_by_one_line()
1207   -- display the lines 2/3/4 with the cursor on line 2
1208   App.screen.init{width=120, height=60}
1209   Editor_state = edit.initialize_test_state()
1210   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
1211   Text.redraw_all(Editor_state)
1212   Editor_state.cursor1 = {line=2, pos=1}
1213   Editor_state.screen_top1 = {line=2, pos=1}
1214   Editor_state.screen_bottom1 = {}
1215   edit.draw(Editor_state)
1216   local y = Editor_state.top
1217   App.screen.check(y, 'def', 'baseline/screen:1')
1218   y = y + Editor_state.line_height
1219   App.screen.check(y, 'ghi', 'baseline/screen:2')
1220   y = y + Editor_state.line_height
1221   App.screen.check(y, 'jkl', 'baseline/screen:3')
1222   -- after hitting the up arrow the screen scrolls up by one line
1223   edit.run_after_keychord(Editor_state, 'up')
1224   check_eq(Editor_state.screen_top1.line, 1, 'screen_top')
1225   check_eq(Editor_state.cursor1.line, 1, 'cursor')
1226   y = Editor_state.top
1227   App.screen.check(y, 'abc', 'screen:1')
1228   y = y + Editor_state.line_height
1229   App.screen.check(y, 'def', 'screen:2')
1230   y = y + Editor_state.line_height
1231   App.screen.check(y, 'ghi', 'screen:3')
1232 end
1233
1234 function test_up_arrow_scrolls_up_by_one_screen_line()
1235   -- display lines starting from second screen line of a line
1236   App.screen.init{width=Editor_state.left+30, height=60}
1237   Editor_state = edit.initialize_test_state()
1238   Editor_state.lines = load_array{'abc', 'def', 'ghi jkl', 'mno'}
1239   Text.redraw_all(Editor_state)
1240   Editor_state.cursor1 = {line=3, pos=6}
1241   Editor_state.screen_top1 = {line=3, pos=5}
1242   Editor_state.screen_bottom1 = {}
1243   edit.draw(Editor_state)
1244   local y = Editor_state.top
1245   App.screen.check(y, 'jkl', 'baseline/screen:1')
1246   y = y + Editor_state.line_height
1247   App.screen.check(y, 'mno', 'baseline/screen:2')
1248   -- after hitting the up arrow the screen scrolls up to first screen line
1249   edit.run_after_keychord(Editor_state, 'up')
1250   y = Editor_state.top
1251   App.screen.check(y, 'ghi ', 'screen:1')
1252   y = y + Editor_state.line_height
1253   App.screen.check(y, 'jkl', 'screen:2')
1254   y = y + Editor_state.line_height
1255   App.screen.check(y, 'mno', 'screen:3')
1256   check_eq(Editor_state.screen_top1.line, 3, 'screen_top:line')
1257   check_eq(Editor_state.screen_top1.pos, 1, 'screen_top:pos')
1258   check_eq(Editor_state.cursor1.line, 3, 'cursor:line')
1259   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
1260 end
1261
1262 function test_up_arrow_scrolls_up_to_final_screen_line()
1263   -- display lines starting just after a long line
1264   App.screen.init{width=Editor_state.left+30, height=60}
1265   Editor_state = edit.initialize_test_state()
1266   Editor_state.lines = load_array{'abc def', 'ghi', 'jkl', 'mno'}
1267   Text.redraw_all(Editor_state)
1268   Editor_state.cursor1 = {line=2, pos=1}
1269   Editor_state.screen_top1 = {line=2, pos=1}
1270   Editor_state.screen_bottom1 = {}
1271   edit.draw(Editor_state)
1272   local y = Editor_state.top
1273   App.screen.check(y, 'ghi', 'baseline/screen:1')
1274   y = y + Editor_state.line_height
1275   App.screen.check(y, 'jkl', 'baseline/screen:2')
1276   y = y + Editor_state.line_height
1277   App.screen.check(y, 'mno', 'baseline/screen:3')
1278   -- after hitting the up arrow the screen scrolls up to final screen line of previous line
1279   edit.run_after_keychord(Editor_state, 'up')
1280   y = Editor_state.top
1281   App.screen.check(y, 'def', 'screen:1')
1282   y = y + Editor_state.line_height
1283   App.screen.check(y, 'ghi', 'screen:2')
1284   y = y + Editor_state.line_height
1285   App.screen.check(y, 'jkl', 'screen:3')
1286   check_eq(Editor_state.screen_top1.line, 1, 'screen_top:line')
1287   check_eq(Editor_state.screen_top1.pos, 5, 'screen_top:pos')
1288   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
1289   check_eq(Editor_state.cursor1.pos, 5, 'cursor:pos')
1290 end
1291
1292 function test_up_arrow_scrolls_up_to_empty_line()
1293   -- display a screenful of text with an empty line just above it outside the screen
1294   App.screen.init{width=120, height=60}
1295   Editor_state = edit.initialize_test_state()
1296   Editor_state.lines = load_array{'', 'abc', 'def', 'ghi', 'jkl'}
1297   Text.redraw_all(Editor_state)
1298   Editor_state.cursor1 = {line=2, pos=1}
1299   Editor_state.screen_top1 = {line=2, pos=1}
1300   Editor_state.screen_bottom1 = {}
1301   edit.draw(Editor_state)
1302   local y = Editor_state.top
1303   App.screen.check(y, 'abc', 'baseline/screen:1')
1304   y = y + Editor_state.line_height
1305   App.screen.check(y, 'def', 'baseline/screen:2')
1306   y = y + Editor_state.line_height
1307   App.screen.check(y, 'ghi', 'baseline/screen:3')
1308   -- after hitting the up arrow the screen scrolls up by one line
1309   edit.run_after_keychord(Editor_state, 'up')
1310   check_eq(Editor_state.screen_top1.line, 1, 'screen_top')
1311   check_eq(Editor_state.cursor1.line, 1, 'cursor')
1312   y = Editor_state.top
1313   -- empty first line
1314   y = y + Editor_state.line_height
1315   App.screen.check(y, 'abc', 'screen:2')
1316   y = y + Editor_state.line_height
1317   App.screen.check(y, 'def', 'screen:3')
1318 end
1319
1320 function test_pageup()
1321   App.screen.init{width=120, height=45}
1322   Editor_state = edit.initialize_test_state()
1323   Editor_state.lines = load_array{'abc', 'def', 'ghi'}
1324   Text.redraw_all(Editor_state)
1325   Editor_state.cursor1 = {line=2, pos=1}
1326   Editor_state.screen_top1 = {line=2, pos=1}
1327   Editor_state.screen_bottom1 = {}
1328   -- initially the last two lines are displayed
1329   edit.draw(Editor_state)
1330   local y = Editor_state.top
1331   App.screen.check(y, 'def', 'baseline/screen:1')
1332   y = y + Editor_state.line_height
1333   App.screen.check(y, 'ghi', 'baseline/screen:2')
1334   -- after pageup the cursor goes to first line
1335   edit.run_after_keychord(Editor_state, 'pageup')
1336   check_eq(Editor_state.screen_top1.line, 1, 'screen_top')
1337   check_eq(Editor_state.cursor1.line, 1, 'cursor')
1338   y = Editor_state.top
1339   App.screen.check(y, 'abc', 'screen:1')
1340   y = y + Editor_state.line_height
1341   App.screen.check(y, 'def', 'screen:2')
1342 end
1343
1344 function test_pageup_scrolls_up_by_screen_line()
1345   -- display the first three lines with the cursor on the bottom line
1346   App.screen.init{width=Editor_state.left+30, height=60}
1347   Editor_state = edit.initialize_test_state()
1348   Editor_state.lines = load_array{'abc def', 'ghi', 'jkl', 'mno'}
1349   Text.redraw_all(Editor_state)
1350   Editor_state.cursor1 = {line=2, pos=1}
1351   Editor_state.screen_top1 = {line=2, pos=1}
1352   Editor_state.screen_bottom1 = {}
1353   edit.draw(Editor_state)
1354   local y = Editor_state.top
1355   App.screen.check(y, 'ghi', 'baseline/screen:1')
1356   y = y + Editor_state.line_height
1357   App.screen.check(y, 'jkl', 'baseline/screen:2')
1358   y = y + Editor_state.line_height
1359   App.screen.check(y, 'mno', 'baseline/screen:3')  -- line wrapping includes trailing whitespace
1360   -- after hitting the page-up key the screen scrolls up to top
1361   edit.run_after_keychord(Editor_state, 'pageup')
1362   check_eq(Editor_state.screen_top1.line, 1, 'screen_top')
1363   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
1364   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
1365   y = Editor_state.top
1366   App.screen.check(y, 'abc ', 'screen:1')
1367   y = y + Editor_state.line_height
1368   App.screen.check(y, 'def', 'screen:2')
1369   y = y + Editor_state.line_height
1370   App.screen.check(y, 'ghi', 'screen:3')
1371 end
1372
1373 function test_pageup_scrolls_up_from_middle_screen_line()
1374   -- display a few lines starting from the middle of a line (Editor_state.cursor1.pos > 1)
1375   App.screen.init{width=Editor_state.left+30, height=60}
1376   Editor_state = edit.initialize_test_state()
1377   Editor_state.lines = load_array{'abc def', 'ghi jkl', 'mno'}
1378   Text.redraw_all(Editor_state)
1379   Editor_state.cursor1 = {line=2, pos=5}
1380   Editor_state.screen_top1 = {line=2, pos=5}
1381   Editor_state.screen_bottom1 = {}
1382   edit.draw(Editor_state)
1383   local y = Editor_state.top
1384   App.screen.check(y, 'jkl', 'baseline/screen:2')
1385   y = y + Editor_state.line_height
1386   App.screen.check(y, 'mno', 'baseline/screen:3')  -- line wrapping includes trailing whitespace
1387   -- after hitting the page-up key the screen scrolls up to top
1388   edit.run_after_keychord(Editor_state, 'pageup')
1389   check_eq(Editor_state.screen_top1.line, 1, 'screen_top')
1390   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
1391   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
1392   y = Editor_state.top
1393   App.screen.check(y, 'abc ', 'screen:1')
1394   y = y + Editor_state.line_height
1395   App.screen.check(y, 'def', 'screen:2')
1396   y = y + Editor_state.line_height
1397   App.screen.check(y, 'ghi ', 'screen:3')
1398 end
1399
1400 function test_enter_on_bottom_line_scrolls_down()
1401   -- display a few lines with cursor on bottom line
1402   App.screen.init{width=Editor_state.left+30, height=60}
1403   Editor_state = edit.initialize_test_state()
1404   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
1405   Text.redraw_all(Editor_state)
1406   Editor_state.cursor1 = {line=3, pos=2}
1407   Editor_state.screen_top1 = {line=1, pos=1}
1408   Editor_state.screen_bottom1 = {}
1409   edit.draw(Editor_state)
1410   local y = Editor_state.top
1411   App.screen.check(y, 'abc', 'baseline/screen:1')
1412   y = y + Editor_state.line_height
1413   App.screen.check(y, 'def', 'baseline/screen:2')
1414   y = y + Editor_state.line_height
1415   App.screen.check(y, 'ghi', 'baseline/screen:3')
1416   -- after hitting the enter key the screen scrolls down
1417   edit.run_after_keychord(Editor_state, 'return')
1418   check_eq(Editor_state.screen_top1.line, 2, 'screen_top')
1419   check_eq(Editor_state.cursor1.line, 4, 'cursor:line')
1420   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
1421   y = Editor_state.top
1422   App.screen.check(y, 'def', 'screen:1')
1423   y = y + Editor_state.line_height
1424   App.screen.check(y, 'g', 'screen:2')
1425   y = y + Editor_state.line_height
1426   App.screen.check(y, 'hi', 'screen:3')
1427 end
1428
1429 function test_enter_on_final_line_avoids_scrolling_down_when_not_at_bottom()
1430   -- display just the bottom line on screen
1431   App.screen.init{width=Editor_state.left+30, height=60}
1432   Editor_state = edit.initialize_test_state()
1433   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
1434   Text.redraw_all(Editor_state)
1435   Editor_state.cursor1 = {line=4, pos=2}
1436   Editor_state.screen_top1 = {line=4, pos=1}
1437   Editor_state.screen_bottom1 = {}
1438   edit.draw(Editor_state)
1439   local y = Editor_state.top
1440   App.screen.check(y, 'jkl', 'baseline/screen:1')
1441   -- after hitting the enter key the screen does not scroll down
1442   edit.run_after_keychord(Editor_state, 'return')
1443   check_eq(Editor_state.screen_top1.line, 4, 'screen_top')
1444   check_eq(Editor_state.cursor1.line, 5, 'cursor:line')
1445   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
1446   y = Editor_state.top
1447   App.screen.check(y, 'j', 'screen:1')
1448   y = y + Editor_state.line_height
1449   App.screen.check(y, 'kl', 'screen:2')
1450 end
1451
1452 function test_inserting_text_on_final_line_avoids_scrolling_down_when_not_at_bottom()
1453   -- display just an empty bottom line on screen
1454   App.screen.init{width=Editor_state.left+30, height=60}
1455   Editor_state = edit.initialize_test_state()
1456   Editor_state.lines = load_array{'abc', ''}
1457   Text.redraw_all(Editor_state)
1458   Editor_state.cursor1 = {line=2, pos=1}
1459   Editor_state.screen_top1 = {line=2, pos=1}
1460   Editor_state.screen_bottom1 = {}
1461   edit.draw(Editor_state)
1462   -- after hitting the inserting_text key the screen does not scroll down
1463   edit.run_after_text_input(Editor_state, 'a')
1464   check_eq(Editor_state.screen_top1.line, 2, 'screen_top')
1465   check_eq(Editor_state.cursor1.line, 2, 'cursor:line')
1466   check_eq(Editor_state.cursor1.pos, 2, 'cursor:pos')
1467   local y = Editor_state.top
1468   App.screen.check(y, 'a', 'screen:1')
1469 end
1470
1471 function test_typing_on_bottom_line_scrolls_down()
1472   -- display a few lines with cursor on bottom line
1473   App.screen.init{width=Editor_state.left+30, height=60}
1474   Editor_state = edit.initialize_test_state()
1475   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
1476   Text.redraw_all(Editor_state)
1477   Editor_state.cursor1 = {line=3, pos=4}
1478   Editor_state.screen_top1 = {line=1, pos=1}
1479   Editor_state.screen_bottom1 = {}
1480   edit.draw(Editor_state)
1481   local y = Editor_state.top
1482   App.screen.check(y, 'abc', 'baseline/screen:1')
1483   y = y + Editor_state.line_height
1484   App.screen.check(y, 'def', 'baseline/screen:2')
1485   y = y + Editor_state.line_height
1486   App.screen.check(y, 'ghi', 'baseline/screen:3')
1487   -- after typing something the line wraps and the screen scrolls down
1488   edit.run_after_text_input(Editor_state, 'j')
1489   edit.run_after_text_input(Editor_state, 'k')
1490   edit.run_after_text_input(Editor_state, 'l')
1491   check_eq(Editor_state.screen_top1.line, 2, 'screen_top')
1492   check_eq(Editor_state.cursor1.line, 3, 'cursor:line')
1493   check_eq(Editor_state.cursor1.pos, 7, 'cursor:pos')
1494   y = Editor_state.top
1495   App.screen.check(y, 'def', 'screen:1')
1496   y = y + Editor_state.line_height
1497   App.screen.check(y, 'ghij', 'screen:2')
1498   y = y + Editor_state.line_height
1499   App.screen.check(y, 'kl', 'screen:3')
1500 end
1501
1502 function test_left_arrow_scrolls_up_in_wrapped_line()
1503   -- display lines starting from second screen line of a line
1504   App.screen.init{width=Editor_state.left+30, height=60}
1505   Editor_state = edit.initialize_test_state()
1506   Editor_state.lines = load_array{'abc', 'def', 'ghi jkl', 'mno'}
1507   Text.redraw_all(Editor_state)
1508   Editor_state.screen_top1 = {line=3, pos=5}
1509   Editor_state.screen_bottom1 = {}
1510   -- cursor is at top of screen
1511   Editor_state.cursor1 = {line=3, pos=5}
1512   edit.draw(Editor_state)
1513   local y = Editor_state.top
1514   App.screen.check(y, 'jkl', 'baseline/screen:1')
1515   y = y + Editor_state.line_height
1516   App.screen.check(y, 'mno', 'baseline/screen:2')
1517   -- after hitting the left arrow the screen scrolls up to first screen line
1518   edit.run_after_keychord(Editor_state, 'left')
1519   y = Editor_state.top
1520   App.screen.check(y, 'ghi ', 'screen:1')
1521   y = y + Editor_state.line_height
1522   App.screen.check(y, 'jkl', 'screen:2')
1523   y = y + Editor_state.line_height
1524   App.screen.check(y, 'mno', 'screen:3')
1525   check_eq(Editor_state.screen_top1.line, 3, 'screen_top:line')
1526   check_eq(Editor_state.screen_top1.pos, 1, 'screen_top:pos')
1527   check_eq(Editor_state.cursor1.line, 3, 'cursor:line')
1528   check_eq(Editor_state.cursor1.pos, 4, 'cursor:pos')
1529 end
1530
1531 function test_right_arrow_scrolls_down_in_wrapped_line()
1532   -- display the first three lines with the cursor on the bottom line
1533   App.screen.init{width=Editor_state.left+30, height=60}
1534   Editor_state = edit.initialize_test_state()
1535   Editor_state.lines = load_array{'abc', 'def', 'ghi jkl', 'mno'}
1536   Text.redraw_all(Editor_state)
1537   Editor_state.screen_top1 = {line=1, pos=1}
1538   Editor_state.screen_bottom1 = {}
1539   -- cursor is at bottom right of screen
1540   Editor_state.cursor1 = {line=3, pos=5}
1541   edit.draw(Editor_state)
1542   local y = Editor_state.top
1543   App.screen.check(y, 'abc', 'baseline/screen:1')
1544   y = y + Editor_state.line_height
1545   App.screen.check(y, 'def', 'baseline/screen:2')
1546   y = y + Editor_state.line_height
1547   App.screen.check(y, 'ghi ', 'baseline/screen:3')  -- line wrapping includes trailing whitespace
1548   -- after hitting the right arrow the screen scrolls down by one line
1549   edit.run_after_keychord(Editor_state, 'right')
1550   check_eq(Editor_state.screen_top1.line, 2, 'screen_top')
1551   check_eq(Editor_state.cursor1.line, 3, 'cursor:line')
1552   check_eq(Editor_state.cursor1.pos, 6, 'cursor:pos')
1553   y = Editor_state.top
1554   App.screen.check(y, 'def', 'screen:1')
1555   y = y + Editor_state.line_height
1556   App.screen.check(y, 'ghi ', 'screen:2')
1557   y = y + Editor_state.line_height
1558   App.screen.check(y, 'jkl', 'screen:3')
1559 end
1560
1561 function test_home_scrolls_up_in_wrapped_line()
1562   -- display lines starting from second screen line of a line
1563   App.screen.init{width=Editor_state.left+30, height=60}
1564   Editor_state = edit.initialize_test_state()
1565   Editor_state.lines = load_array{'abc', 'def', 'ghi jkl', 'mno'}
1566   Text.redraw_all(Editor_state)
1567   Editor_state.screen_top1 = {line=3, pos=5}
1568   Editor_state.screen_bottom1 = {}
1569   -- cursor is at top of screen
1570   Editor_state.cursor1 = {line=3, pos=5}
1571   edit.draw(Editor_state)
1572   local y = Editor_state.top
1573   App.screen.check(y, 'jkl', 'baseline/screen:1')
1574   y = y + Editor_state.line_height
1575   App.screen.check(y, 'mno', 'baseline/screen:2')
1576   -- after hitting home the screen scrolls up to first screen line
1577   edit.run_after_keychord(Editor_state, 'home')
1578   y = Editor_state.top
1579   App.screen.check(y, 'ghi ', 'screen:1')
1580   y = y + Editor_state.line_height
1581   App.screen.check(y, 'jkl', 'screen:2')
1582   y = y + Editor_state.line_height
1583   App.screen.check(y, 'mno', 'screen:3')
1584   check_eq(Editor_state.screen_top1.line, 3, 'screen_top:line')
1585   check_eq(Editor_state.screen_top1.pos, 1, 'screen_top:pos')
1586   check_eq(Editor_state.cursor1.line, 3, 'cursor:line')
1587   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
1588 end
1589
1590 function test_end_scrolls_down_in_wrapped_line()
1591   -- display the first three lines with the cursor on the bottom line
1592   App.screen.init{width=Editor_state.left+30, height=60}
1593   Editor_state = edit.initialize_test_state()
1594   Editor_state.lines = load_array{'abc', 'def', 'ghi jkl', 'mno'}
1595   Text.redraw_all(Editor_state)
1596   Editor_state.screen_top1 = {line=1, pos=1}
1597   Editor_state.screen_bottom1 = {}
1598   -- cursor is at bottom right of screen
1599   Editor_state.cursor1 = {line=3, pos=5}
1600   edit.draw(Editor_state)
1601   local y = Editor_state.top
1602   App.screen.check(y, 'abc', 'baseline/screen:1')
1603   y = y + Editor_state.line_height
1604   App.screen.check(y, 'def', 'baseline/screen:2')
1605   y = y + Editor_state.line_height
1606   App.screen.check(y, 'ghi ', 'baseline/screen:3')  -- line wrapping includes trailing whitespace
1607   -- after hitting end the screen scrolls down by one line
1608   edit.run_after_keychord(Editor_state, 'end')
1609   check_eq(Editor_state.screen_top1.line, 2, 'screen_top')
1610   check_eq(Editor_state.cursor1.line, 3, 'cursor:line')
1611   check_eq(Editor_state.cursor1.pos, 8, 'cursor:pos')
1612   y = Editor_state.top
1613   App.screen.check(y, 'def', 'screen:1')
1614   y = y + Editor_state.line_height
1615   App.screen.check(y, 'ghi ', 'screen:2')
1616   y = y + Editor_state.line_height
1617   App.screen.check(y, 'jkl', 'screen:3')
1618 end
1619
1620 function test_position_cursor_on_recently_edited_wrapping_line()
1621   -- draw a line wrapping over 2 screen lines
1622   App.screen.init{width=100, height=200}
1623   Editor_state = edit.initialize_test_state()
1624   Editor_state.lines = load_array{'abc def ghi jkl mno pqr ', 'xyz'}
1625   Text.redraw_all(Editor_state)
1626   Editor_state.cursor1 = {line=1, pos=25}
1627   Editor_state.screen_top1 = {line=1, pos=1}
1628   Editor_state.screen_bottom1 = {}
1629   edit.draw(Editor_state)
1630   local y = Editor_state.top
1631   App.screen.check(y, 'abc def ghi ', 'baseline1/screen:1')
1632   y = y + Editor_state.line_height
1633   App.screen.check(y, 'jkl mno pqr ', 'baseline1/screen:2')
1634   y = y + Editor_state.line_height
1635   App.screen.check(y, 'xyz', 'baseline1/screen:3')
1636   -- add to the line until it's wrapping over 3 screen lines
1637   edit.run_after_text_input(Editor_state, 's')
1638   edit.run_after_text_input(Editor_state, 't')
1639   edit.run_after_text_input(Editor_state, 'u')
1640   check_eq(Editor_state.cursor1.pos, 28, 'cursor:pos')
1641   y = Editor_state.top
1642   App.screen.check(y, 'abc def ghi ', 'baseline2/screen:1')
1643   y = y + Editor_state.line_height
1644   App.screen.check(y, 'jkl mno pqr ', 'baseline2/screen:2')
1645   y = y + Editor_state.line_height
1646   App.screen.check(y, 'stu', 'baseline2/screen:3')
1647   -- try to move the cursor earlier in the third screen line by clicking the mouse
1648   edit.run_after_mouse_release(Editor_state, Editor_state.left+8,Editor_state.top+Editor_state.line_height*2+5, 1)
1649   -- cursor should move
1650   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
1651   check_eq(Editor_state.cursor1.pos, 26, 'cursor:pos')
1652 end
1653
1654 function test_backspace_can_scroll_up()
1655   -- display the lines 2/3/4 with the cursor on line 2
1656   App.screen.init{width=120, height=60}
1657   Editor_state = edit.initialize_test_state()
1658   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
1659   Text.redraw_all(Editor_state)
1660   Editor_state.cursor1 = {line=2, pos=1}
1661   Editor_state.screen_top1 = {line=2, pos=1}
1662   Editor_state.screen_bottom1 = {}
1663   edit.draw(Editor_state)
1664   local y = Editor_state.top
1665   App.screen.check(y, 'def', 'baseline/screen:1')
1666   y = y + Editor_state.line_height
1667   App.screen.check(y, 'ghi', 'baseline/screen:2')
1668   y = y + Editor_state.line_height
1669   App.screen.check(y, 'jkl', 'baseline/screen:3')
1670   -- after hitting backspace the screen scrolls up by one line
1671   edit.run_after_keychord(Editor_state, 'backspace')
1672   check_eq(Editor_state.screen_top1.line, 1, 'screen_top')
1673   check_eq(Editor_state.cursor1.line, 1, 'cursor')
1674   y = Editor_state.top
1675   App.screen.check(y, 'abcdef', 'screen:1')
1676   y = y + Editor_state.line_height
1677   App.screen.check(y, 'ghi', 'screen:2')
1678   y = y + Editor_state.line_height
1679   App.screen.check(y, 'jkl', 'screen:3')
1680 end
1681
1682 function test_backspace_can_scroll_up_screen_line()
1683   -- display lines starting from second screen line of a line
1684   App.screen.init{width=Editor_state.left+30, height=60}
1685   Editor_state = edit.initialize_test_state()
1686   Editor_state.lines = load_array{'abc', 'def', 'ghi jkl', 'mno'}
1687   Text.redraw_all(Editor_state)
1688   Editor_state.cursor1 = {line=3, pos=5}
1689   Editor_state.screen_top1 = {line=3, pos=5}
1690   Editor_state.screen_bottom1 = {}
1691   edit.draw(Editor_state)
1692   local y = Editor_state.top
1693   App.screen.check(y, 'jkl', 'baseline/screen:1')
1694   y = y + Editor_state.line_height
1695   App.screen.check(y, 'mno', 'baseline/screen:2')
1696   -- after hitting backspace the screen scrolls up by one screen line
1697   edit.run_after_keychord(Editor_state, 'backspace')
1698   y = Editor_state.top
1699   App.screen.check(y, 'ghij', 'screen:1')
1700   y = y + Editor_state.line_height
1701   App.screen.check(y, 'kl', 'screen:2')
1702   y = y + Editor_state.line_height
1703   App.screen.check(y, 'mno', 'screen:3')
1704   check_eq(Editor_state.screen_top1.line, 3, 'screen_top:line')
1705   check_eq(Editor_state.screen_top1.pos, 1, 'screen_top:pos')
1706   check_eq(Editor_state.cursor1.line, 3, 'cursor:line')
1707   check_eq(Editor_state.cursor1.pos, 4, 'cursor:pos')
1708 end
1709
1710 function test_backspace_past_line_boundary()
1711   -- position cursor at start of a (non-first) line
1712   App.screen.init{width=Editor_state.left+30, height=60}
1713   Editor_state = edit.initialize_test_state()
1714   Editor_state.lines = load_array{'abc', 'def'}
1715   Text.redraw_all(Editor_state)
1716   Editor_state.cursor1 = {line=2, pos=1}
1717   -- backspace joins with previous line
1718   edit.run_after_keychord(Editor_state, 'backspace')
1719   check_eq(Editor_state.lines[1].data, 'abcdef', 'check')
1720 end
1721
1722 -- some tests for operating over selections created using Shift- chords
1723 -- we're just testing delete_selection, and it works the same for all keys
1724
1725 function test_backspace_over_selection()
1726   -- select just one character within a line with cursor before selection
1727   App.screen.init{width=Editor_state.left+30, height=60}
1728   Editor_state = edit.initialize_test_state()
1729   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl', 'mno'}
1730   Text.redraw_all(Editor_state)
1731   Editor_state.cursor1 = {line=1, pos=1}
1732   Editor_state.selection1 = {line=1, pos=2}
1733   -- backspace deletes the selected character, even though it's after the cursor
1734   edit.run_after_keychord(Editor_state, 'backspace')
1735   check_eq(Editor_state.lines[1].data, 'bc', 'data')
1736   -- cursor (remains) at start of selection
1737   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
1738   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
1739   -- selection is cleared
1740   check_nil(Editor_state.selection1.line, 'selection')
1741 end
1742
1743 function test_backspace_over_selection_reverse()
1744   -- select just one character within a line with cursor after selection
1745   App.screen.init{width=Editor_state.left+30, height=60}
1746   Editor_state = edit.initialize_test_state()
1747   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl', 'mno'}
1748   Text.redraw_all(Editor_state)
1749   Editor_state.cursor1 = {line=1, pos=2}
1750   Editor_state.selection1 = {line=1, pos=1}
1751   -- backspace deletes the selected character
1752   edit.run_after_keychord(Editor_state, 'backspace')
1753   check_eq(Editor_state.lines[1].data, 'bc', 'data')
1754   -- cursor moves to start of selection
1755   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
1756   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
1757   -- selection is cleared
1758   check_nil(Editor_state.selection1.line, 'selection')
1759 end
1760
1761 function test_backspace_over_multiple_lines()
1762   -- select just one character within a line with cursor after selection
1763   App.screen.init{width=Editor_state.left+30, height=60}
1764   Editor_state = edit.initialize_test_state()
1765   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl', 'mno'}
1766   Text.redraw_all(Editor_state)
1767   Editor_state.cursor1 = {line=1, pos=2}
1768   Editor_state.selection1 = {line=4, pos=2}
1769   -- backspace deletes the region and joins the remaining portions of lines on either side
1770   edit.run_after_keychord(Editor_state, 'backspace')
1771   check_eq(Editor_state.lines[1].data, 'akl', 'data:1')
1772   check_eq(Editor_state.lines[2].data, 'mno', 'data:2')
1773   -- cursor remains at start of selection
1774   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
1775   check_eq(Editor_state.cursor1.pos, 2, 'cursor:pos')
1776   -- selection is cleared
1777   check_nil(Editor_state.selection1.line, 'selection')
1778 end
1779
1780 function test_backspace_to_end_of_line()
1781   -- select region from cursor to end of line
1782   App.screen.init{width=Editor_state.left+30, height=60}
1783   Editor_state = edit.initialize_test_state()
1784   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl', 'mno'}
1785   Text.redraw_all(Editor_state)
1786   Editor_state.cursor1 = {line=1, pos=2}
1787   Editor_state.selection1 = {line=1, pos=4}
1788   -- backspace deletes rest of line without joining to any other line
1789   edit.run_after_keychord(Editor_state, 'backspace')
1790   check_eq(Editor_state.lines[1].data, 'a', 'data:1')
1791   check_eq(Editor_state.lines[2].data, 'def', 'data:2')
1792   -- cursor remains at start of selection
1793   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
1794   check_eq(Editor_state.cursor1.pos, 2, 'cursor:pos')
1795   -- selection is cleared
1796   check_nil(Editor_state.selection1.line, 'selection')
1797 end
1798
1799 function test_backspace_to_start_of_line()
1800   -- select region from cursor to start of line
1801   App.screen.init{width=Editor_state.left+30, height=60}
1802   Editor_state = edit.initialize_test_state()
1803   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl', 'mno'}
1804   Text.redraw_all(Editor_state)
1805   Editor_state.cursor1 = {line=2, pos=1}
1806   Editor_state.selection1 = {line=2, pos=3}
1807   -- backspace deletes beginning of line without joining to any other line
1808   edit.run_after_keychord(Editor_state, 'backspace')
1809   check_eq(Editor_state.lines[1].data, 'abc', 'data:1')
1810   check_eq(Editor_state.lines[2].data, 'f', 'data:2')
1811   -- cursor remains at start of selection
1812   check_eq(Editor_state.cursor1.line, 2, 'cursor:line')
1813   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
1814   -- selection is cleared
1815   check_nil(Editor_state.selection1.line, 'selection')
1816 end
1817
1818 function test_undo_insert_text()
1819   App.screen.init{width=120, height=60}
1820   Editor_state = edit.initialize_test_state()
1821   Editor_state.lines = load_array{'abc', 'def', 'xyz'}
1822   Text.redraw_all(Editor_state)
1823   Editor_state.cursor1 = {line=2, pos=4}
1824   Editor_state.screen_top1 = {line=1, pos=1}
1825   Editor_state.screen_bottom1 = {}
1826   -- insert a character
1827   edit.draw(Editor_state)
1828   edit.run_after_text_input(Editor_state, 'g')
1829   check_eq(Editor_state.cursor1.line, 2, 'baseline/cursor:line')
1830   check_eq(Editor_state.cursor1.pos, 5, 'baseline/cursor:pos')
1831   check_nil(Editor_state.selection1.line, 'baseline/selection:line')
1832   check_nil(Editor_state.selection1.pos, 'baseline/selection:pos')
1833   local y = Editor_state.top
1834   App.screen.check(y, 'abc', 'baseline/screen:1')
1835   y = y + Editor_state.line_height
1836   App.screen.check(y, 'defg', 'baseline/screen:2')
1837   y = y + Editor_state.line_height
1838   App.screen.check(y, 'xyz', 'baseline/screen:3')
1839   -- undo
1840   edit.run_after_keychord(Editor_state, 'C-z')
1841   check_eq(Editor_state.cursor1.line, 2, 'cursor:line')
1842   check_eq(Editor_state.cursor1.pos, 4, 'cursor:pos')
1843   check_nil(Editor_state.selection1.line, 'selection:line')
1844   check_nil(Editor_state.selection1.pos, 'selection:pos')
1845   y = Editor_state.top
1846   App.screen.check(y, 'abc', 'screen:1')
1847   y = y + Editor_state.line_height
1848   App.screen.check(y, 'def', 'screen:2')
1849   y = y + Editor_state.line_height
1850   App.screen.check(y, 'xyz', 'screen:3')
1851 end
1852
1853 function test_undo_delete_text()
1854   App.screen.init{width=120, height=60}
1855   Editor_state = edit.initialize_test_state()
1856   Editor_state.lines = load_array{'abc', 'defg', 'xyz'}
1857   Text.redraw_all(Editor_state)
1858   Editor_state.cursor1 = {line=2, pos=5}
1859   Editor_state.screen_top1 = {line=1, pos=1}
1860   Editor_state.screen_bottom1 = {}
1861   -- delete a character
1862   edit.run_after_keychord(Editor_state, 'backspace')
1863   check_eq(Editor_state.cursor1.line, 2, 'baseline/cursor:line')
1864   check_eq(Editor_state.cursor1.pos, 4, 'baseline/cursor:pos')
1865   check_nil(Editor_state.selection1.line, 'baseline/selection:line')
1866   check_nil(Editor_state.selection1.pos, 'baseline/selection:pos')
1867   local y = Editor_state.top
1868   App.screen.check(y, 'abc', 'baseline/screen:1')
1869   y = y + Editor_state.line_height
1870   App.screen.check(y, 'def', 'baseline/screen:2')
1871   y = y + Editor_state.line_height
1872   App.screen.check(y, 'xyz', 'baseline/screen:3')
1873   -- undo
1874 --?   -- after undo, the backspaced key is selected
1875   edit.run_after_keychord(Editor_state, 'C-z')
1876   check_eq(Editor_state.cursor1.line, 2, 'cursor:line')
1877   check_eq(Editor_state.cursor1.pos, 5, 'cursor:pos')
1878   check_nil(Editor_state.selection1.line, 'selection:line')
1879   check_nil(Editor_state.selection1.pos, 'selection:pos')
1880 --?   check_eq(Editor_state.selection1.line, 2, 'selection:line')
1881 --?   check_eq(Editor_state.selection1.pos, 4, 'selection:pos')
1882   y = Editor_state.top
1883   App.screen.check(y, 'abc', 'screen:1')
1884   y = y + Editor_state.line_height
1885   App.screen.check(y, 'defg', 'screen:2')
1886   y = y + Editor_state.line_height
1887   App.screen.check(y, 'xyz', 'screen:3')
1888 end
1889
1890 function test_undo_restores_selection()
1891   -- display a line of text with some part selected
1892   App.screen.init{width=75, height=80}
1893   Editor_state = edit.initialize_test_state()
1894   Editor_state.lines = load_array{'abc'}
1895   Text.redraw_all(Editor_state)
1896   Editor_state.cursor1 = {line=1, pos=1}
1897   Editor_state.selection1 = {line=1, pos=2}
1898   Editor_state.screen_top1 = {line=1, pos=1}
1899   Editor_state.screen_bottom1 = {}
1900   edit.draw(Editor_state)
1901   -- delete selected text
1902   edit.run_after_text_input(Editor_state, 'x')
1903   check_eq(Editor_state.lines[1].data, 'xbc', 'baseline')
1904   check_nil(Editor_state.selection1.line, 'baseline:selection')
1905   -- undo
1906   edit.run_after_keychord(Editor_state, 'C-z')
1907   edit.run_after_keychord(Editor_state, 'C-z')
1908   -- selection is restored
1909   check_eq(Editor_state.selection1.line, 1, 'line')
1910   check_eq(Editor_state.selection1.pos, 2, 'pos')
1911 end
1912
1913 function test_search()
1914   App.screen.init{width=120, height=60}
1915   Editor_state = edit.initialize_test_state()
1916   Editor_state.lines = load_array{'```lines', '```', 'def', 'ghi', 'deg'}
1917   Text.redraw_all(Editor_state)
1918   Editor_state.cursor1 = {line=1, pos=1}
1919   Editor_state.screen_top1 = {line=1, pos=1}
1920   Editor_state.screen_bottom1 = {}
1921   edit.draw(Editor_state)
1922   -- search for a string
1923   edit.run_after_keychord(Editor_state, 'C-f')
1924   edit.run_after_text_input(Editor_state, 'd')
1925   edit.run_after_keychord(Editor_state, 'return')
1926   check_eq(Editor_state.cursor1.line, 2, '1/cursor:line')
1927   check_eq(Editor_state.cursor1.pos, 1, '1/cursor:pos')
1928   -- reset cursor
1929   Editor_state.cursor1 = {line=1, pos=1}
1930   Editor_state.screen_top1 = {line=1, pos=1}
1931   -- search for second occurrence
1932   edit.run_after_keychord(Editor_state, 'C-f')
1933   edit.run_after_text_input(Editor_state, 'de')
1934   edit.run_after_keychord(Editor_state, 'down')
1935   edit.run_after_keychord(Editor_state, 'return')
1936   check_eq(Editor_state.cursor1.line, 4, '2/cursor:line')
1937   check_eq(Editor_state.cursor1.pos, 1, '2/cursor:pos')
1938 end
1939
1940 function test_search_upwards()
1941   App.screen.init{width=120, height=60}
1942   Editor_state = edit.initialize_test_state()
1943   Editor_state.lines = load_array{'abc abd'}
1944   Text.redraw_all(Editor_state)
1945   Editor_state.cursor1 = {line=1, pos=2}
1946   Editor_state.screen_top1 = {line=1, pos=1}
1947   Editor_state.screen_bottom1 = {}
1948   edit.draw(Editor_state)
1949   -- search for a string
1950   edit.run_after_keychord(Editor_state, 'C-f')
1951   edit.run_after_text_input(Editor_state, 'a')
1952   -- search for previous occurrence
1953   edit.run_after_keychord(Editor_state, 'up')
1954   check_eq(Editor_state.cursor1.line, 1, '2/cursor:line')
1955   check_eq(Editor_state.cursor1.pos, 1, '2/cursor:pos')
1956 end
1957
1958 function test_search_wrap()
1959   App.screen.init{width=120, height=60}
1960   Editor_state = edit.initialize_test_state()
1961   Editor_state.lines = load_array{'abc'}
1962   Text.redraw_all(Editor_state)
1963   Editor_state.cursor1 = {line=1, pos=3}
1964   Editor_state.screen_top1 = {line=1, pos=1}
1965   Editor_state.screen_bottom1 = {}
1966   edit.draw(Editor_state)
1967   -- search for a string
1968   edit.run_after_keychord(Editor_state, 'C-f')
1969   edit.run_after_text_input(Editor_state, 'a')
1970   edit.run_after_keychord(Editor_state, 'return')
1971   -- cursor wraps
1972   check_eq(Editor_state.cursor1.line, 1, '1/cursor:line')
1973   check_eq(Editor_state.cursor1.pos, 1, '1/cursor:pos')
1974 end
1975
1976 function test_search_wrap_upwards()
1977   App.screen.init{width=120, height=60}
1978   Editor_state = edit.initialize_test_state()
1979   Editor_state.lines = load_array{'abc abd'}
1980   Text.redraw_all(Editor_state)
1981   Editor_state.cursor1 = {line=1, pos=1}
1982   Editor_state.screen_top1 = {line=1, pos=1}
1983   Editor_state.screen_bottom1 = {}
1984   edit.draw(Editor_state)
1985   -- search upwards for a string
1986   edit.run_after_keychord(Editor_state, 'C-f')
1987   edit.run_after_text_input(Editor_state, 'a')
1988   edit.run_after_keychord(Editor_state, 'up')
1989   -- cursor wraps
1990   check_eq(Editor_state.cursor1.line, 1, '1/cursor:line')
1991   check_eq(Editor_state.cursor1.pos, 5, '1/cursor:pos')
1992 end