text_tests.lua

   1 -- major tests for text editing flows
   2 -- Arguably this should be called edit_tests.lua,
   3 -- but that would mess up the git blame at this point.
   4
   5 function test_initial_state()
   6   App.screen.init{width=120, height=60}
   7   Editor_state = edit.initialize_test_state()
   8   Editor_state.lines = load_array{}
   9   Text.redraw_all(Editor_state)
  10   edit.draw(Editor_state)
  11   check_eq(#Editor_state.lines, 1, '#lines')
  12   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
  13   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
  14   check_eq(Editor_state.screen_top1.line, 1, 'screen_top:line')
  15   check_eq(Editor_state.screen_top1.pos, 1, 'screen_top:pos')
  16 end
  17
  18 function test_click_to_create_drawing()
  19   App.screen.init{width=120, height=60}
  20   Editor_state = edit.initialize_test_state()
  21   Editor_state.lines = load_array{}
  22   Text.redraw_all(Editor_state)
  23   edit.draw(Editor_state)
  24   edit.run_after_mouse_click(Editor_state, 8,Editor_state.top+8, 1)
  25   -- cursor skips drawing to always remain on text
  26   check_eq(#Editor_state.lines, 2, '#lines')
  27   check_eq(Editor_state.cursor1.line, 2, 'cursor')
  28 end
  29
  30 function test_backspace_to_delete_drawing()
  31   -- display a drawing followed by a line of text (you shouldn't ever have a drawing right at the end)
  32   App.screen.init{width=120, height=60}
  33   Editor_state = edit.initialize_test_state()
  34   Editor_state.lines = load_array{'```lines', '```', ''}
  35   Text.redraw_all(Editor_state)
  36   -- cursor is on text as always (outside tests this will get initialized correctly)
  37   Editor_state.cursor1.line = 2
  38   -- backspacing deletes the drawing
  39   edit.run_after_keychord(Editor_state, 'backspace')
  40   check_eq(#Editor_state.lines, 1, '#lines')
  41   check_eq(Editor_state.cursor1.line, 1, 'cursor')
  42 end
  43
  44 function test_backspace_from_start_of_final_line()
  45   -- display final line of text with cursor at start of it
  46   App.screen.init{width=120, height=60}
  47   Editor_state = edit.initialize_test_state()
  48   Editor_state.lines = load_array{'abc', 'def'}
  49   Editor_state.screen_top1 = {line=2, pos=1}
  50   Editor_state.cursor1 = {line=2, pos=1}
  51   Text.redraw_all(Editor_state)
  52   -- backspace scrolls up
  53   edit.run_after_keychord(Editor_state, 'backspace')
  54   check_eq(#Editor_state.lines, 1, '#lines')
  55   check_eq(Editor_state.cursor1.line, 1, 'cursor')
  56   check_eq(Editor_state.screen_top1.line, 1, 'screen_top')
  57 end
  58
  59 function test_insert_first_character()
  60   App.screen.init{width=120, height=60}
  61   Editor_state = edit.initialize_test_state()
  62   Editor_state.lines = load_array{}
  63   Text.redraw_all(Editor_state)
  64   edit.draw(Editor_state)
  65   edit.run_after_text_input(Editor_state, 'a')
  66   local y = Editor_state.top
  67   App.screen.check(y, 'a', 'screen:1')
  68 end
  69
  70 function test_press_ctrl()
  71   -- press ctrl while the cursor is on text
  72   App.screen.init{width=50, height=80}
  73   Editor_state = edit.initialize_test_state()
  74   Editor_state.lines = load_array{''}
  75   Text.redraw_all(Editor_state)
  76   Editor_state.cursor1 = {line=1, pos=1}
  77   Editor_state.screen_top1 = {line=1, pos=1}
  78   Editor_state.screen_bottom1 = {}
  79   edit.run_after_keychord(Editor_state, 'C-m')
  80 end
  81
  82 function test_move_left()
  83   App.screen.init{width=120, height=60}
  84   Editor_state = edit.initialize_test_state()
  85   Editor_state.lines = load_array{'a'}
  86   Text.redraw_all(Editor_state)
  87   Editor_state.cursor1 = {line=1, pos=2}
  88   edit.draw(Editor_state)
  89   edit.run_after_keychord(Editor_state, 'left')
  90   check_eq(Editor_state.cursor1.pos, 1, 'check')
  91 end
  92
  93 function test_move_right()
  94   App.screen.init{width=120, height=60}
  95   Editor_state = edit.initialize_test_state()
  96   Editor_state.lines = load_array{'a'}
  97   Text.redraw_all(Editor_state)
  98   Editor_state.cursor1 = {line=1, pos=1}
  99   edit.draw(Editor_state)
 100   edit.run_after_keychord(Editor_state, 'right')
 101   check_eq(Editor_state.cursor1.pos, 2, 'check')
 102 end
 103
 104 function test_move_left_to_previous_line()
 105   App.screen.init{width=120, height=60}
 106   Editor_state = edit.initialize_test_state()
 107   Editor_state.lines = load_array{'abc', 'def'}
 108   Text.redraw_all(Editor_state)
 109   Editor_state.cursor1 = {line=2, pos=1}
 110   edit.draw(Editor_state)
 111   edit.run_after_keychord(Editor_state, 'left')
 112   check_eq(Editor_state.cursor1.line, 1, 'line')
 113   check_eq(Editor_state.cursor1.pos, 4, 'pos')  -- past end of line
 114 end
 115
 116 function test_move_right_to_next_line()
 117   App.screen.init{width=120, height=60}
 118   Editor_state = edit.initialize_test_state()
 119   Editor_state.lines = load_array{'abc', 'def'}
 120   Text.redraw_all(Editor_state)
 121   Editor_state.cursor1 = {line=1, pos=4}  -- past end of line
 122   edit.draw(Editor_state)
 123   edit.run_after_keychord(Editor_state, 'right')
 124   check_eq(Editor_state.cursor1.line, 2, 'line')
 125   check_eq(Editor_state.cursor1.pos, 1, 'pos')
 126 end
 127
 128 function test_move_to_start_of_word()
 129   App.screen.init{width=120, height=60}
 130   Editor_state = edit.initialize_test_state()
 131   Editor_state.lines = load_array{'abc'}
 132   Text.redraw_all(Editor_state)
 133   Editor_state.cursor1 = {line=1, pos=3}
 134   edit.draw(Editor_state)
 135   edit.run_after_keychord(Editor_state, 'M-left')
 136   check_eq(Editor_state.cursor1.pos, 1, 'check')
 137 end
 138
 139 function test_move_to_start_of_previous_word()
 140   App.screen.init{width=120, height=60}
 141   Editor_state = edit.initialize_test_state()
 142   Editor_state.lines = load_array{'abc def'}
 143   Text.redraw_all(Editor_state)
 144   Editor_state.cursor1 = {line=1, pos=4}  -- at the space between words
 145   edit.draw(Editor_state)
 146   edit.run_after_keychord(Editor_state, 'M-left')
 147   check_eq(Editor_state.cursor1.pos, 1, 'check')
 148 end
 149
 150 function test_skip_to_previous_word()
 151   App.screen.init{width=120, height=60}
 152   Editor_state = edit.initialize_test_state()
 153   Editor_state.lines = load_array{'abc def'}
 154   Text.redraw_all(Editor_state)
 155   Editor_state.cursor1 = {line=1, pos=5}  -- at the start of second word
 156   edit.draw(Editor_state)
 157   edit.run_after_keychord(Editor_state, 'M-left')
 158   check_eq(Editor_state.cursor1.pos, 1, 'check')
 159 end
 160
 161 function test_skip_past_tab_to_previous_word()
 162   App.screen.init{width=120, height=60}
 163   Editor_state = edit.initialize_test_state()
 164   Editor_state.lines = load_array{'abc def\tghi'}
 165   Text.redraw_all(Editor_state)
 166   Editor_state.cursor1 = {line=1, pos=10}  -- within third word
 167   edit.draw(Editor_state)
 168   edit.run_after_keychord(Editor_state, 'M-left')
 169   check_eq(Editor_state.cursor1.pos, 9, 'check')
 170 end
 171
 172 function test_skip_multiple_spaces_to_previous_word()
 173   App.screen.init{width=120, height=60}
 174   Editor_state = edit.initialize_test_state()
 175   Editor_state.lines = load_array{'abc  def'}
 176   Text.redraw_all(Editor_state)
 177   Editor_state.cursor1 = {line=1, pos=6}  -- at the start of second word
 178   edit.draw(Editor_state)
 179   edit.run_after_keychord(Editor_state, 'M-left')
 180   check_eq(Editor_state.cursor1.pos, 1, 'check')
 181 end
 182
 183 function test_move_to_start_of_word_on_previous_line()
 184   App.screen.init{width=120, height=60}
 185   Editor_state = edit.initialize_test_state()
 186   Editor_state.lines = load_array{'abc def', 'ghi'}
 187   Text.redraw_all(Editor_state)
 188   Editor_state.cursor1 = {line=2, pos=1}
 189   edit.draw(Editor_state)
 190   edit.run_after_keychord(Editor_state, 'M-left')
 191   check_eq(Editor_state.cursor1.line, 1, 'line')
 192   check_eq(Editor_state.cursor1.pos, 5, 'pos')
 193 end
 194
 195 function test_move_past_end_of_word()
 196   App.screen.init{width=120, height=60}
 197   Editor_state = edit.initialize_test_state()
 198   Editor_state.lines = load_array{'abc def'}
 199   Text.redraw_all(Editor_state)
 200   Editor_state.cursor1 = {line=1, pos=1}
 201   edit.draw(Editor_state)
 202   edit.run_after_keychord(Editor_state, 'M-right')
 203   check_eq(Editor_state.cursor1.pos, 4, 'check')
 204 end
 205
 206 function test_skip_to_next_word()
 207   App.screen.init{width=120, height=60}
 208   Editor_state = edit.initialize_test_state()
 209   Editor_state.lines = load_array{'abc def'}
 210   Text.redraw_all(Editor_state)
 211   Editor_state.cursor1 = {line=1, pos=4}  -- at the space between words
 212   edit.draw(Editor_state)
 213   edit.run_after_keychord(Editor_state, 'M-right')
 214   check_eq(Editor_state.cursor1.pos, 8, 'check')
 215 end
 216
 217 function test_skip_past_tab_to_next_word()
 218   App.screen.init{width=120, height=60}
 219   Editor_state = edit.initialize_test_state()
 220   Editor_state.lines = load_array{'abc\tdef'}
 221   Text.redraw_all(Editor_state)
 222   Editor_state.cursor1 = {line=1, pos=1}  -- at the space between words
 223   edit.draw(Editor_state)
 224   edit.run_after_keychord(Editor_state, 'M-right')
 225   check_eq(Editor_state.cursor1.pos, 4, 'check')
 226 end
 227
 228 function test_skip_multiple_spaces_to_next_word()
 229   App.screen.init{width=120, height=60}
 230   Editor_state = edit.initialize_test_state()
 231   Editor_state.lines = load_array{'abc  def'}
 232   Text.redraw_all(Editor_state)
 233   Editor_state.cursor1 = {line=1, pos=4}  -- at the start of second word
 234   edit.draw(Editor_state)
 235   edit.run_after_keychord(Editor_state, 'M-right')
 236   check_eq(Editor_state.cursor1.pos, 9, 'check')
 237 end
 238
 239 function test_move_past_end_of_word_on_next_line()
 240   App.screen.init{width=120, height=60}
 241   Editor_state = edit.initialize_test_state()
 242   Editor_state.lines = load_array{'abc def', 'ghi'}
 243   Text.redraw_all(Editor_state)
 244   Editor_state.cursor1 = {line=1, pos=8}
 245   edit.draw(Editor_state)
 246   edit.run_after_keychord(Editor_state, 'M-right')
 247   check_eq(Editor_state.cursor1.line, 2, 'line')
 248   check_eq(Editor_state.cursor1.pos, 4, 'pos')
 249 end
 250
 251 function test_click_moves_cursor()
 252   App.screen.init{width=50, height=60}
 253   Editor_state = edit.initialize_test_state()
 254   Editor_state.lines = load_array{'abc', 'def', 'xyz'}
 255   Text.redraw_all(Editor_state)
 256   Editor_state.cursor1 = {line=1, pos=1}
 257   Editor_state.screen_top1 = {line=1, pos=1}
 258   Editor_state.screen_bottom1 = {}
 259   Editor_state.selection1 = {}
 260   edit.draw(Editor_state)  -- populate line_cache.starty for each line Editor_state.line_cache
 261   edit.run_after_mouse_release(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
 262   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
 263   check_eq(Editor_state.cursor1.pos, 2, 'cursor:pos')
 264   -- selection is empty to avoid perturbing future edits
 265   check_nil(Editor_state.selection1.line, 'selection:line')
 266   check_nil(Editor_state.selection1.pos, 'selection:pos')
 267 end
 268
 269 function test_click_to_left_of_line()
 270   -- display a line with the cursor in the middle
 271   App.screen.init{width=50, height=80}
 272   Editor_state = edit.initialize_test_state()
 273   Editor_state.lines = load_array{'abc'}
 274   Text.redraw_all(Editor_state)
 275   Editor_state.cursor1 = {line=1, pos=3}
 276   Editor_state.screen_top1 = {line=1, pos=1}
 277   Editor_state.screen_bottom1 = {}
 278   Editor_state.selection1 = {}
 279   -- click to the left of the line
 280   edit.draw(Editor_state)
 281   edit.run_after_mouse_click(Editor_state, Editor_state.left-4,Editor_state.top+5, 1)
 282   -- cursor moves to start of line
 283   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
 284   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
 285   check_nil(Editor_state.selection1.line, 'selection is empty to avoid perturbing future edits')
 286 end
 287
 288 function test_click_takes_margins_into_account()
 289   -- display two lines with cursor on one of them
 290   App.screen.init{width=100, height=80}
 291   Editor_state = edit.initialize_test_state()
 292   Editor_state.left = 50  -- occupy only right side of screen
 293   Editor_state.lines = load_array{'abc', 'def'}
 294   Text.redraw_all(Editor_state)
 295   Editor_state.cursor1 = {line=2, pos=1}
 296   Editor_state.screen_top1 = {line=1, pos=1}
 297   Editor_state.screen_bottom1 = {}
 298   Editor_state.selection1 = {}
 299   -- click on the other line
 300   edit.draw(Editor_state)
 301   edit.run_after_mouse_click(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
 302   -- cursor moves
 303   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
 304   check_eq(Editor_state.cursor1.pos, 2, 'cursor:pos')
 305   check_nil(Editor_state.selection1.line, 'selection is empty to avoid perturbing future edits')
 306 end
 307
 308 function test_click_on_empty_line()
 309   -- display two lines with the first one empty
 310   App.screen.init{width=50, height=80}
 311   Editor_state = edit.initialize_test_state()
 312   Editor_state.lines = load_array{'', 'def'}
 313   Text.redraw_all(Editor_state)
 314   Editor_state.cursor1 = {line=2, pos=1}
 315   Editor_state.screen_top1 = {line=1, pos=1}
 316   Editor_state.screen_bottom1 = {}
 317   Editor_state.selection1 = {}
 318   -- click on the empty line
 319   edit.draw(Editor_state)
 320   edit.run_after_mouse_click(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
 321   -- cursor moves
 322   check_eq(Editor_state.cursor1.line, 1, 'cursor')
 323   -- selection remains empty
 324   check_nil(Editor_state.selection1.line, 'selection is empty to avoid perturbing future edits')
 325 end
 326
 327 function test_click_below_all_lines()
 328   -- display one line
 329   App.screen.init{width=50, height=80}
 330   Editor_state = edit.initialize_test_state()
 331   Editor_state.lines = load_array{'abc'}
 332   Text.redraw_all(Editor_state)
 333   Editor_state.cursor1 = {line=1, pos=1}
 334   Editor_state.screen_top1 = {line=1, pos=1}
 335   Editor_state.screen_bottom1 = {}
 336   Editor_state.selection1 = {}
 337   -- click below first line
 338   edit.draw(Editor_state)
 339   edit.run_after_mouse_click(Editor_state, Editor_state.left+8,Editor_state.top+50, 1)
 340   -- cursor doesn't move
 341   check_eq(Editor_state.cursor1.line, 1, 'cursor')
 342   -- selection remains empty
 343   check_nil(Editor_state.selection1.line, 'selection is empty to avoid perturbing future edits')
 344 end
 345
 346 function test_draw_text()
 347   App.screen.init{width=120, height=60}
 348   Editor_state = edit.initialize_test_state()
 349   Editor_state.lines = load_array{'abc', 'def', 'ghi'}
 350   Text.redraw_all(Editor_state)
 351   Editor_state.cursor1 = {line=1, pos=1}
 352   Editor_state.screen_top1 = {line=1, pos=1}
 353   Editor_state.screen_bottom1 = {}
 354   edit.draw(Editor_state)
 355   local y = Editor_state.top
 356   App.screen.check(y, 'abc', 'screen:1')
 357   y = y + Editor_state.line_height
 358   App.screen.check(y, 'def', 'screen:2')
 359   y = y + Editor_state.line_height
 360   App.screen.check(y, 'ghi', 'screen:3')
 361 end
 362
 363 function test_draw_wrapping_text()
 364   App.screen.init{width=50, height=60}
 365   Editor_state = edit.initialize_test_state()
 366   Editor_state.lines = load_array{'abc', 'defgh', 'xyz'}
 367   Text.redraw_all(Editor_state)
 368   Editor_state.cursor1 = {line=1, pos=1}
 369   Editor_state.screen_top1 = {line=1, pos=1}
 370   Editor_state.screen_bottom1 = {}
 371   edit.draw(Editor_state)
 372   local y = Editor_state.top
 373   App.screen.check(y, 'abc', 'screen:1')
 374   y = y + Editor_state.line_height
 375   App.screen.check(y, 'de', 'screen:2')
 376   y = y + Editor_state.line_height
 377   App.screen.check(y, 'fgh', 'screen:3')
 378 end
 379
 380 function test_draw_word_wrapping_text()
 381   App.screen.init{width=60, height=60}
 382   Editor_state = edit.initialize_test_state()
 383   Editor_state.lines = load_array{'abc def ghi', 'jkl'}
 384   Text.redraw_all(Editor_state)
 385   Editor_state.cursor1 = {line=1, pos=1}
 386   Editor_state.screen_top1 = {line=1, pos=1}
 387   Editor_state.screen_bottom1 = {}
 388   edit.draw(Editor_state)
 389   local y = Editor_state.top
 390   App.screen.check(y, 'abc ', 'screen:1')
 391   y = y + Editor_state.line_height
 392   App.screen.check(y, 'def ', 'screen:2')
 393   y = y + Editor_state.line_height
 394   App.screen.check(y, 'ghi', 'screen:3')
 395 end
 396
 397 function test_click_on_wrapping_line()
 398   -- display two screen lines with cursor on one of them
 399   App.screen.init{width=50, height=80}
 400   Editor_state = edit.initialize_test_state()
 401   Editor_state.lines = load_array{'abc def ghi jkl mno pqr stu'}
 402   Text.redraw_all(Editor_state)
 403   Editor_state.cursor1 = {line=1, pos=20}
 404   Editor_state.screen_top1 = {line=1, pos=1}
 405   Editor_state.screen_bottom1 = {}
 406   -- click on the other line
 407   edit.draw(Editor_state)
 408   edit.run_after_mouse_click(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
 409   -- cursor moves
 410   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
 411   check_eq(Editor_state.cursor1.pos, 2, 'cursor:pos')
 412   check_nil(Editor_state.selection1.line, 'selection is empty to avoid perturbing future edits')
 413 end
 414
 415 function test_click_on_wrapping_line_takes_margins_into_account()
 416   -- display two screen lines with cursor on one of them
 417   App.screen.init{width=100, height=80}
 418   Editor_state = edit.initialize_test_state()
 419   Editor_state.left = 50  -- occupy only right side of screen
 420   Editor_state.lines = load_array{'abc def ghi jkl mno pqr stu'}
 421   Text.redraw_all(Editor_state)
 422   Editor_state.cursor1 = {line=1, pos=20}
 423   Editor_state.screen_top1 = {line=1, pos=1}
 424   Editor_state.screen_bottom1 = {}
 425   -- click on the other line
 426   edit.draw(Editor_state)
 427   edit.run_after_mouse_click(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
 428   -- cursor moves
 429   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
 430   check_eq(Editor_state.cursor1.pos, 2, 'cursor:pos')
 431   check_nil(Editor_state.selection1.line, 'selection is empty to avoid perturbing future edits')
 432 end
 433
 434 function test_draw_text_wrapping_within_word()
 435   -- arrange a screen line that needs to be split within a word
 436   App.screen.init{width=60, height=60}
 437   Editor_state = edit.initialize_test_state()
 438   Editor_state.lines = load_array{'abcd e fghijk', 'xyz'}
 439   Text.redraw_all(Editor_state)
 440   Editor_state.cursor1 = {line=1, pos=1}
 441   Editor_state.screen_top1 = {line=1, pos=1}
 442   Editor_state.screen_bottom1 = {}
 443   edit.draw(Editor_state)
 444   local y = Editor_state.top
 445   App.screen.check(y, 'abcd ', 'screen:1')
 446   y = y + Editor_state.line_height
 447   App.screen.check(y, 'e fgh', 'screen:2')
 448   y = y + Editor_state.line_height
 449   App.screen.check(y, 'ijk', 'screen:3')
 450 end
 451
 452 function test_draw_wrapping_text_containing_non_ascii()
 453   -- draw a long line containing non-ASCII
 454   App.screen.init{width=60, height=60}
 455   Editor_state = edit.initialize_test_state()
 456   Editor_state.lines = load_array{'madam I’m adam', 'xyz'}  -- notice the non-ASCII apostrophe
 457   Text.redraw_all(Editor_state)
 458   Editor_state.cursor1 = {line=1, pos=1}
 459   Editor_state.screen_top1 = {line=1, pos=1}
 460   Editor_state.screen_bottom1 = {}
 461   edit.draw(Editor_state)
 462   local y = Editor_state.top
 463   App.screen.check(y, 'mad', 'screen:1')
 464   y = y + Editor_state.line_height
 465   App.screen.check(y, 'am I', 'screen:2')
 466   y = y + Editor_state.line_height
 467   App.screen.check(y, '’m a', 'screen:3')
 468 end
 469
 470 function test_click_past_end_of_screen_line()
 471   -- display a wrapping line
 472   App.screen.init{width=75, height=80}
 473   Editor_state = edit.initialize_test_state()
 474                                --  12345678901234
 475   Editor_state.lines = load_array{"madam I'm adam"}
 476   Text.redraw_all(Editor_state)
 477   Editor_state.cursor1 = {line=1, pos=1}
 478   Editor_state.screen_top1 = {line=1, pos=1}
 479   Editor_state.screen_bottom1 = {}
 480   edit.draw(Editor_state)
 481   local y = Editor_state.top
 482   App.screen.check(y, 'madam ', 'baseline/screen:1')
 483   y = y + Editor_state.line_height
 484   App.screen.check(y, "I'm ad", 'baseline/screen:2')
 485   y = y + Editor_state.line_height
 486   -- click past end of second screen line
 487   edit.run_after_mouse_click(Editor_state, App.screen.width-2,y-2, 1)
 488   -- cursor moves to end of screen line
 489   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
 490   check_eq(Editor_state.cursor1.pos, 12, 'cursor:pos')
 491 end
 492
 493 function test_click_on_wrapping_line_rendered_from_partway_at_top_of_screen()
 494   -- display a wrapping line from its second screen line
 495   App.screen.init{width=75, height=80}
 496   Editor_state = edit.initialize_test_state()
 497                                --  12345678901234
 498   Editor_state.lines = load_array{"madam I'm adam"}
 499   Text.redraw_all(Editor_state)
 500   Editor_state.cursor1 = {line=1, pos=8}
 501   Editor_state.screen_top1 = {line=1, pos=7}
 502   Editor_state.screen_bottom1 = {}
 503   edit.draw(Editor_state)
 504   local y = Editor_state.top
 505   App.screen.check(y, "I'm ad", 'baseline/screen:2')
 506   y = y + Editor_state.line_height
 507   -- click past end of second screen line
 508   edit.run_after_mouse_click(Editor_state, App.screen.width-2,y-2, 1)
 509   -- cursor moves to end of screen line
 510   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
 511   check_eq(Editor_state.cursor1.pos, 12, 'cursor:pos')
 512 end
 513
 514 function test_click_past_end_of_wrapping_line()
 515   -- display a wrapping line
 516   App.screen.init{width=75, height=80}
 517   Editor_state = edit.initialize_test_state()
 518                                --  12345678901234
 519   Editor_state.lines = load_array{"madam I'm adam"}
 520   Text.redraw_all(Editor_state)
 521   Editor_state.cursor1 = {line=1, pos=1}
 522   Editor_state.screen_top1 = {line=1, pos=1}
 523   Editor_state.screen_bottom1 = {}
 524   edit.draw(Editor_state)
 525   local y = Editor_state.top
 526   App.screen.check(y, 'madam ', 'baseline/screen:1')
 527   y = y + Editor_state.line_height
 528   App.screen.check(y, "I'm ad", 'baseline/screen:2')
 529   y = y + Editor_state.line_height
 530   App.screen.check(y, 'am', 'baseline/screen:3')
 531   y = y + Editor_state.line_height
 532   -- click past the end of it
 533   edit.run_after_mouse_click(Editor_state, App.screen.width-2,y-2, 1)
 534   -- cursor moves to end of line
 535   check_eq(Editor_state.cursor1.pos, 15, 'cursor')  -- one more than the number of UTF-8 code-points
 536 end
 537
 538 function test_click_past_end_of_wrapping_line_containing_non_ascii()
 539   -- display a wrapping line containing non-ASCII
 540   App.screen.init{width=75, height=80}
 541   Editor_state = edit.initialize_test_state()
 542                                --  12345678901234
 543   Editor_state.lines = load_array{'madam I’m adam'}  -- notice the non-ASCII apostrophe
 544   Text.redraw_all(Editor_state)
 545   Editor_state.cursor1 = {line=1, pos=1}
 546   Editor_state.screen_top1 = {line=1, pos=1}
 547   Editor_state.screen_bottom1 = {}
 548   edit.draw(Editor_state)
 549   local y = Editor_state.top
 550   App.screen.check(y, 'madam ', 'baseline/screen:1')
 551   y = y + Editor_state.line_height
 552   App.screen.check(y, 'I’m ad', 'baseline/screen:2')
 553   y = y + Editor_state.line_height
 554   App.screen.check(y, 'am', 'baseline/screen:3')
 555   y = y + Editor_state.line_height
 556   -- click past the end of it
 557   edit.run_after_mouse_click(Editor_state, App.screen.width-2,y-2, 1)
 558   -- cursor moves to end of line
 559   check_eq(Editor_state.cursor1.pos, 15, 'cursor')  -- one more than the number of UTF-8 code-points
 560 end
 561
 562 function test_click_past_end_of_word_wrapping_line()
 563   -- display a long line wrapping at a word boundary on a screen of more realistic length
 564   App.screen.init{width=160, height=80}
 565   Editor_state = edit.initialize_test_state()
 566                                 -- 0        1         2
 567                                 -- 123456789012345678901
 568   Editor_state.lines = load_array{'the quick brown fox jumped over the lazy dog'}
 569   Text.redraw_all(Editor_state)
 570   Editor_state.cursor1 = {line=1, pos=1}
 571   Editor_state.screen_top1 = {line=1, pos=1}
 572   Editor_state.screen_bottom1 = {}
 573   edit.draw(Editor_state)
 574   local y = Editor_state.top
 575   App.screen.check(y, 'the quick brown fox ', 'baseline/screen:1')
 576   y = y + Editor_state.line_height
 577   -- click past the end of the screen line
 578   edit.run_after_mouse_click(Editor_state, App.screen.width-2,y-2, 1)
 579   -- cursor moves to end of screen line
 580   check_eq(Editor_state.cursor1.pos, 20, 'cursor')
 581 end
 582
 583 function test_select_text()
 584   -- display a line of text
 585   App.screen.init{width=75, height=80}
 586   Editor_state = edit.initialize_test_state()
 587   Editor_state.lines = load_array{'abc def'}
 588   Text.redraw_all(Editor_state)
 589   Editor_state.cursor1 = {line=1, pos=1}
 590   Editor_state.screen_top1 = {line=1, pos=1}
 591   Editor_state.screen_bottom1 = {}
 592   edit.draw(Editor_state)
 593   -- select a letter
 594   App.fake_key_press('lshift')
 595   edit.run_after_keychord(Editor_state, 'S-right')
 596   App.fake_key_release('lshift')
 597   edit.key_release(Editor_state, 'lshift')
 598   -- selection persists even after shift is released
 599   check_eq(Editor_state.selection1.line, 1, 'selection:line')
 600   check_eq(Editor_state.selection1.pos, 1, 'selection:pos')
 601   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
 602   check_eq(Editor_state.cursor1.pos, 2, 'cursor:pos')
 603 end
 604
 605 function test_cursor_movement_without_shift_resets_selection()
 606   -- display a line of text with some part selected
 607   App.screen.init{width=75, height=80}
 608   Editor_state = edit.initialize_test_state()
 609   Editor_state.lines = load_array{'abc'}
 610   Text.redraw_all(Editor_state)
 611   Editor_state.cursor1 = {line=1, pos=1}
 612   Editor_state.selection1 = {line=1, pos=2}
 613   Editor_state.screen_top1 = {line=1, pos=1}
 614   Editor_state.screen_bottom1 = {}
 615   edit.draw(Editor_state)
 616   -- press an arrow key without shift
 617   edit.run_after_keychord(Editor_state, 'right')
 618   -- no change to data, selection is reset
 619   check_nil(Editor_state.selection1.line, 'check')
 620   check_eq(Editor_state.lines[1].data, 'abc', 'data')
 621 end
 622
 623 function test_edit_deletes_selection()
 624   -- display a line of text with some part selected
 625   App.screen.init{width=75, height=80}
 626   Editor_state = edit.initialize_test_state()
 627   Editor_state.lines = load_array{'abc'}
 628   Text.redraw_all(Editor_state)
 629   Editor_state.cursor1 = {line=1, pos=1}
 630   Editor_state.selection1 = {line=1, pos=2}
 631   Editor_state.screen_top1 = {line=1, pos=1}
 632   Editor_state.screen_bottom1 = {}
 633   edit.draw(Editor_state)
 634   -- press a key
 635   edit.run_after_text_input(Editor_state, 'x')
 636   -- selected text is deleted and replaced with the key
 637   check_eq(Editor_state.lines[1].data, 'xbc', 'check')
 638 end
 639
 640 function test_edit_with_shift_key_deletes_selection()
 641   -- display a line of text with some part selected
 642   App.screen.init{width=75, height=80}
 643   Editor_state = edit.initialize_test_state()
 644   Editor_state.lines = load_array{'abc'}
 645   Text.redraw_all(Editor_state)
 646   Editor_state.cursor1 = {line=1, pos=1}
 647   Editor_state.selection1 = {line=1, pos=2}
 648   Editor_state.screen_top1 = {line=1, pos=1}
 649   Editor_state.screen_bottom1 = {}
 650   edit.draw(Editor_state)
 651   -- mimic precise keypresses for a capital letter
 652   App.fake_key_press('lshift')
 653   edit.keychord_press(Editor_state, 'd', 'd')
 654   edit.text_input(Editor_state, 'D')
 655   edit.key_release(Editor_state, 'd')
 656   App.fake_key_release('lshift')
 657   -- selected text is deleted and replaced with the key
 658   check_nil(Editor_state.selection1.line, 'check')
 659   check_eq(Editor_state.lines[1].data, 'Dbc', 'data')
 660 end
 661
 662 function test_copy_does_not_reset_selection()
 663   -- display a line of text with a selection
 664   App.screen.init{width=75, height=80}
 665   Editor_state = edit.initialize_test_state()
 666   Editor_state.lines = load_array{'abc'}
 667   Text.redraw_all(Editor_state)
 668   Editor_state.cursor1 = {line=1, pos=1}
 669   Editor_state.selection1 = {line=1, pos=2}
 670   Editor_state.screen_top1 = {line=1, pos=1}
 671   Editor_state.screen_bottom1 = {}
 672   edit.draw(Editor_state)
 673   -- copy selection
 674   edit.run_after_keychord(Editor_state, 'C-c')
 675   check_eq(App.clipboard, 'a', 'clipboard')
 676   -- selection is reset since shift key is not pressed
 677   check(Editor_state.selection1.line, 'check')
 678 end
 679
 680 function test_cut()
 681   -- display a line of text with some part selected
 682   App.screen.init{width=75, height=80}
 683   Editor_state = edit.initialize_test_state()
 684   Editor_state.lines = load_array{'abc'}
 685   Text.redraw_all(Editor_state)
 686   Editor_state.cursor1 = {line=1, pos=1}
 687   Editor_state.selection1 = {line=1, pos=2}
 688   Editor_state.screen_top1 = {line=1, pos=1}
 689   Editor_state.screen_bottom1 = {}
 690   edit.draw(Editor_state)
 691   -- press a key
 692   edit.run_after_keychord(Editor_state, 'C-x')
 693   check_eq(App.clipboard, 'a', 'clipboard')
 694   -- selected text is deleted
 695   check_eq(Editor_state.lines[1].data, 'bc', 'data')
 696 end
 697
 698 function test_paste_replaces_selection()
 699   -- display a line of text with a selection
 700   App.screen.init{width=75, height=80}
 701   Editor_state = edit.initialize_test_state()
 702   Editor_state.lines = load_array{'abc', 'def'}
 703   Text.redraw_all(Editor_state)
 704   Editor_state.cursor1 = {line=2, pos=1}
 705   Editor_state.selection1 = {line=1, pos=1}
 706   Editor_state.screen_top1 = {line=1, pos=1}
 707   Editor_state.screen_bottom1 = {}
 708   edit.draw(Editor_state)
 709   -- set clipboard
 710   App.clipboard = 'xyz'
 711   -- paste selection
 712   edit.run_after_keychord(Editor_state, 'C-v')
 713   -- selection is reset since shift key is not pressed
 714   -- selection includes the newline, so it's also deleted
 715   check_eq(Editor_state.lines[1].data, 'xyzdef', 'check')
 716 end
 717
 718 function test_deleting_selection_may_scroll()
 719   -- display lines 2/3/4
 720   App.screen.init{width=120, height=60}
 721   Editor_state = edit.initialize_test_state()
 722   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
 723   Text.redraw_all(Editor_state)
 724   Editor_state.cursor1 = {line=3, pos=2}
 725   Editor_state.screen_top1 = {line=2, pos=1}
 726   Editor_state.screen_bottom1 = {}
 727   edit.draw(Editor_state)
 728   local y = Editor_state.top
 729   App.screen.check(y, 'def', 'baseline/screen:1')
 730   y = y + Editor_state.line_height
 731   App.screen.check(y, 'ghi', 'baseline/screen:2')
 732   y = y + Editor_state.line_height
 733   App.screen.check(y, 'jkl', 'baseline/screen:3')
 734   -- set up a selection starting above the currently displayed page
 735   Editor_state.selection1 = {line=1, pos=2}
 736   -- delete selection
 737   edit.run_after_keychord(Editor_state, 'backspace')
 738   -- page scrolls up
 739   check_eq(Editor_state.screen_top1.line, 1, 'check')
 740   check_eq(Editor_state.lines[1].data, 'ahi', 'data')
 741 end
 742
 743 function test_edit_wrapping_text()
 744   App.screen.init{width=50, height=60}
 745   Editor_state = edit.initialize_test_state()
 746   Editor_state.lines = load_array{'abc', 'def', 'xyz'}
 747   Text.redraw_all(Editor_state)
 748   Editor_state.cursor1 = {line=2, pos=4}
 749   Editor_state.screen_top1 = {line=1, pos=1}
 750   Editor_state.screen_bottom1 = {}
 751   edit.draw(Editor_state)
 752   edit.run_after_text_input(Editor_state, 'g')
 753   local y = Editor_state.top
 754   App.screen.check(y, 'abc', 'screen:1')
 755   y = y + Editor_state.line_height
 756   App.screen.check(y, 'de', 'screen:2')
 757   y = y + Editor_state.line_height
 758   App.screen.check(y, 'fg', 'screen:3')
 759 end
 760
 761 function test_insert_newline()
 762   -- display a few lines
 763   App.screen.init{width=Editor_state.left+30, height=60}
 764   Editor_state = edit.initialize_test_state()
 765   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
 766   Text.redraw_all(Editor_state)
 767   Editor_state.cursor1 = {line=1, pos=2}
 768   Editor_state.screen_top1 = {line=1, pos=1}
 769   Editor_state.screen_bottom1 = {}
 770   edit.draw(Editor_state)
 771   local y = Editor_state.top
 772   App.screen.check(y, 'abc', 'baseline/screen:1')
 773   y = y + Editor_state.line_height
 774   App.screen.check(y, 'def', 'baseline/screen:2')
 775   y = y + Editor_state.line_height
 776   App.screen.check(y, 'ghi', 'baseline/screen:3')
 777   -- hitting the enter key splits the line
 778   edit.run_after_keychord(Editor_state, 'return')
 779   check_eq(Editor_state.screen_top1.line, 1, 'screen_top')
 780   check_eq(Editor_state.cursor1.line, 2, 'cursor:line')
 781   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
 782   y = Editor_state.top
 783   App.screen.check(y, 'a', 'screen:1')
 784   y = y + Editor_state.line_height
 785   App.screen.check(y, 'bc', 'screen:2')
 786   y = y + Editor_state.line_height
 787   App.screen.check(y, 'def', 'screen:3')
 788 end
 789
 790 function test_insert_newline_at_start_of_line()
 791   -- display a line
 792   App.screen.init{width=Editor_state.left+30, height=60}
 793   Editor_state = edit.initialize_test_state()
 794   Editor_state.lines = load_array{'abc'}
 795   Text.redraw_all(Editor_state)
 796   Editor_state.cursor1 = {line=1, pos=1}
 797   Editor_state.screen_top1 = {line=1, pos=1}
 798   Editor_state.screen_bottom1 = {}
 799   -- hitting the enter key splits the line
 800   edit.run_after_keychord(Editor_state, 'return')
 801   check_eq(Editor_state.cursor1.line, 2, 'cursor:line')
 802   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
 803   check_eq(Editor_state.lines[1].data, '', 'data:1')
 804   check_eq(Editor_state.lines[2].data, 'abc', 'data:2')
 805 end
 806
 807 function test_insert_from_clipboard()
 808   -- display a few lines
 809   App.screen.init{width=Editor_state.left+30, height=60}
 810   Editor_state = edit.initialize_test_state()
 811   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
 812   Text.redraw_all(Editor_state)
 813   Editor_state.cursor1 = {line=1, pos=2}
 814   Editor_state.screen_top1 = {line=1, pos=1}
 815   Editor_state.screen_bottom1 = {}
 816   edit.draw(Editor_state)
 817   local y = Editor_state.top
 818   App.screen.check(y, 'abc', 'baseline/screen:1')
 819   y = y + Editor_state.line_height
 820   App.screen.check(y, 'def', 'baseline/screen:2')
 821   y = y + Editor_state.line_height
 822   App.screen.check(y, 'ghi', 'baseline/screen:3')
 823   -- paste some text including a newline, check that new line is created
 824   App.clipboard = 'xy\nz'
 825   edit.run_after_keychord(Editor_state, 'C-v')
 826   check_eq(Editor_state.screen_top1.line, 1, 'screen_top')
 827   check_eq(Editor_state.cursor1.line, 2, 'cursor:line')
 828   check_eq(Editor_state.cursor1.pos, 2, 'cursor:pos')
 829   y = Editor_state.top
 830   App.screen.check(y, 'axy', 'screen:1')
 831   y = y + Editor_state.line_height
 832   App.screen.check(y, 'zbc', 'screen:2')
 833   y = y + Editor_state.line_height
 834   App.screen.check(y, 'def', 'screen:3')
 835 end
 836
 837 function test_select_text_using_mouse()
 838   App.screen.init{width=50, height=60}
 839   Editor_state = edit.initialize_test_state()
 840   Editor_state.lines = load_array{'abc', 'def', 'xyz'}
 841   Text.redraw_all(Editor_state)
 842   Editor_state.cursor1 = {line=1, pos=1}
 843   Editor_state.screen_top1 = {line=1, pos=1}
 844   Editor_state.screen_bottom1 = {}
 845   Editor_state.selection1 = {}
 846   edit.draw(Editor_state)  -- populate line_cache.starty for each line Editor_state.line_cache
 847   -- press and hold on first location
 848   edit.run_after_mouse_press(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
 849   -- drag and release somewhere else
 850   edit.run_after_mouse_release(Editor_state, Editor_state.left+20,Editor_state.top+Editor_state.line_height+5, 1)
 851   check_eq(Editor_state.selection1.line, 1, 'selection:line')
 852   check_eq(Editor_state.selection1.pos, 2, 'selection:pos')
 853   check_eq(Editor_state.cursor1.line, 2, 'cursor:line')
 854   check_eq(Editor_state.cursor1.pos, 4, 'cursor:pos')
 855 end
 856
 857 function test_select_text_using_mouse_starting_above_text()
 858   App.screen.init{width=50, height=60}
 859   Editor_state = edit.initialize_test_state()
 860   Editor_state.lines = load_array{'abc', 'def', 'xyz'}
 861   Text.redraw_all(Editor_state)
 862   Editor_state.cursor1 = {line=1, pos=1}
 863   Editor_state.screen_top1 = {line=1, pos=1}
 864   Editor_state.screen_bottom1 = {}
 865   Editor_state.selection1 = {}
 866   edit.draw(Editor_state)  -- populate line_cache.starty for each line Editor_state.line_cache
 867   -- press mouse above first line of text
 868   edit.run_after_mouse_press(Editor_state, Editor_state.left+8,5, 1)
 869   check(Editor_state.selection1.line ~= nil, 'selection:line-not-nil')
 870   check_eq(Editor_state.selection1.line, 1, 'selection:line')
 871   check_eq(Editor_state.selection1.pos, 1, 'selection:pos')
 872 end
 873
 874 function test_select_text_using_mouse_starting_above_text_wrapping_line()
 875   -- first screen line starts in the middle of a line
 876   App.screen.init{width=50, height=60}
 877   Editor_state = edit.initialize_test_state()
 878   Editor_state.lines = load_array{'abc', 'defgh', 'xyz'}
 879   Text.redraw_all(Editor_state)
 880   Editor_state.cursor1 = {line=2, pos=5}
 881   Editor_state.screen_top1 = {line=2, pos=3}
 882   Editor_state.screen_bottom1 = {}
 883   -- press mouse above first line of text
 884   edit.draw(Editor_state)
 885   edit.run_after_mouse_press(Editor_state, Editor_state.left+8,5, 1)
 886   -- selection is at screen top
 887   check(Editor_state.selection1.line ~= nil, 'selection:line-not-nil')
 888   check_eq(Editor_state.selection1.line, 2, 'selection:line')
 889   check_eq(Editor_state.selection1.pos, 3, 'selection:pos')
 890 end
 891
 892 function test_select_text_using_mouse_starting_below_text()
 893   -- I'd like to test what happens when a mouse click is below some page of
 894   -- text, potentially even in the middle of a line.
 895   -- However, it's brittle to set up a text line boundary just right.
 896   -- So I'm going to just check things below the bottom of the final line of
 897   -- text when it's in the middle of the screen.
 898   -- final screen line ends in the middle of screen
 899   App.screen.init{width=50, height=60}
 900   Editor_state = edit.initialize_test_state()
 901   Editor_state.lines = load_array{'abcde'}
 902   Text.redraw_all(Editor_state)
 903   Editor_state.cursor1 = {line=1, pos=1}
 904   Editor_state.screen_top1 = {line=1, pos=1}
 905   Editor_state.screen_bottom1 = {}
 906   edit.draw(Editor_state)
 907   local y = Editor_state.top
 908   App.screen.check(y, 'ab', 'baseline:screen:1')
 909   y = y + Editor_state.line_height
 910   App.screen.check(y, 'cde', 'baseline:screen:2')
 911   -- press mouse above first line of text
 912   edit.run_after_mouse_press(Editor_state, 5,App.screen.height-5, 1)
 913   -- selection is past bottom-most text in screen
 914   check(Editor_state.selection1.line ~= nil, 'selection:line-not-nil')
 915   check_eq(Editor_state.selection1.line, 1, 'selection:line')
 916   check_eq(Editor_state.selection1.pos, 6, 'selection:pos')
 917 end
 918
 919 function test_select_text_using_mouse_and_shift()
 920   App.screen.init{width=50, height=60}
 921   Editor_state = edit.initialize_test_state()
 922   Editor_state.lines = load_array{'abc', 'def', 'xyz'}
 923   Text.redraw_all(Editor_state)
 924   Editor_state.cursor1 = {line=1, pos=1}
 925   Editor_state.screen_top1 = {line=1, pos=1}
 926   Editor_state.screen_bottom1 = {}
 927   Editor_state.selection1 = {}
 928   edit.draw(Editor_state)  -- populate line_cache.starty for each line Editor_state.line_cache
 929   -- click on first location
 930   edit.run_after_mouse_press(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
 931   edit.run_after_mouse_release(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
 932   -- hold down shift and click somewhere else
 933   App.fake_key_press('lshift')
 934   edit.run_after_mouse_press(Editor_state, Editor_state.left+20,Editor_state.top+5, 1)
 935   edit.run_after_mouse_release(Editor_state, Editor_state.left+20,Editor_state.top+Editor_state.line_height+5, 1)
 936   App.fake_key_release('lshift')
 937   check_eq(Editor_state.selection1.line, 1, 'selection:line')
 938   check_eq(Editor_state.selection1.pos, 2, 'selection:pos')
 939   check_eq(Editor_state.cursor1.line, 2, 'cursor:line')
 940   check_eq(Editor_state.cursor1.pos, 4, 'cursor:pos')
 941 end
 942
 943 function test_select_text_repeatedly_using_mouse_and_shift()
 944   App.screen.init{width=50, height=60}
 945   Editor_state = edit.initialize_test_state()
 946   Editor_state.lines = load_array{'abc', 'def', 'xyz'}
 947   Text.redraw_all(Editor_state)
 948   Text.redraw_all(Editor_state)
 949   Editor_state.cursor1 = {line=1, pos=1}
 950   Editor_state.screen_top1 = {line=1, pos=1}
 951   Editor_state.screen_bottom1 = {}
 952   Editor_state.selection1 = {}
 953   edit.draw(Editor_state)  -- populate line_cache.starty for each line Editor_state.line_cache
 954   -- click on first location
 955   edit.run_after_mouse_press(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
 956   edit.run_after_mouse_release(Editor_state, Editor_state.left+8,Editor_state.top+5, 1)
 957   -- hold down shift and click on a second location
 958   App.fake_key_press('lshift')
 959   edit.run_after_mouse_press(Editor_state, Editor_state.left+20,Editor_state.top+5, 1)
 960   edit.run_after_mouse_release(Editor_state, Editor_state.left+20,Editor_state.top+Editor_state.line_height+5, 1)
 961   -- hold down shift and click at a third location
 962   App.fake_key_press('lshift')
 963   edit.run_after_mouse_press(Editor_state, Editor_state.left+20,Editor_state.top+5, 1)
 964   edit.run_after_mouse_release(Editor_state, Editor_state.left+8,Editor_state.top+Editor_state.line_height+5, 1)
 965   App.fake_key_release('lshift')
 966   -- selection is between first and third location. forget the second location, not the first.
 967   check_eq(Editor_state.selection1.line, 1, 'selection:line')
 968   check_eq(Editor_state.selection1.pos, 2, 'selection:pos')
 969   check_eq(Editor_state.cursor1.line, 2, 'cursor:line')
 970   check_eq(Editor_state.cursor1.pos, 2, 'cursor:pos')
 971 end
 972
 973 function test_select_all_text()
 974   -- display a single line of text
 975   App.screen.init{width=75, height=80}
 976   Editor_state = edit.initialize_test_state()
 977   Editor_state.lines = load_array{'abc def'}
 978   Text.redraw_all(Editor_state)
 979   Editor_state.cursor1 = {line=1, pos=1}
 980   Editor_state.screen_top1 = {line=1, pos=1}
 981   Editor_state.screen_bottom1 = {}
 982   edit.draw(Editor_state)
 983   -- select all
 984   App.fake_key_press('lctrl')
 985   edit.run_after_keychord(Editor_state, 'C-a')
 986   App.fake_key_release('lctrl')
 987   edit.key_release(Editor_state, 'lctrl')
 988   -- selection
 989   check_eq(Editor_state.selection1.line, 1, 'selection:line')
 990   check_eq(Editor_state.selection1.pos, 1, 'selection:pos')
 991   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
 992   check_eq(Editor_state.cursor1.pos, 8, 'cursor:pos')
 993 end
 994
 995 function test_cut_without_selection()
 996   -- display a few lines
 997   App.screen.init{width=Editor_state.left+30, height=60}
 998   Editor_state = edit.initialize_test_state()
 999   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
1000   Text.redraw_all(Editor_state)
1001   Editor_state.cursor1 = {line=1, pos=2}
1002   Editor_state.screen_top1 = {line=1, pos=1}
1003   Editor_state.screen_bottom1 = {}
1004   Editor_state.selection1 = {}
1005   edit.draw(Editor_state)
1006   -- try to cut without selecting text
1007   edit.run_after_keychord(Editor_state, 'C-x')
1008   -- no crash
1009   check_nil(Editor_state.selection1.line, 'check')
1010 end
1011
1012 function test_pagedown()
1013   App.screen.init{width=120, height=45}
1014   Editor_state = edit.initialize_test_state()
1015   Editor_state.lines = load_array{'abc', 'def', 'ghi'}
1016   Text.redraw_all(Editor_state)
1017   Editor_state.cursor1 = {line=1, pos=1}
1018   Editor_state.screen_top1 = {line=1, pos=1}
1019   Editor_state.screen_bottom1 = {}
1020   -- initially the first two lines are displayed
1021   edit.draw(Editor_state)
1022   local y = Editor_state.top
1023   App.screen.check(y, 'abc', 'baseline/screen:1')
1024   y = y + Editor_state.line_height
1025   App.screen.check(y, 'def', 'baseline/screen:2')
1026   -- after pagedown the bottom line becomes the top
1027   edit.run_after_keychord(Editor_state, 'pagedown')
1028   check_eq(Editor_state.screen_top1.line, 2, 'screen_top')
1029   check_eq(Editor_state.cursor1.line, 2, 'cursor')
1030   y = Editor_state.top
1031   App.screen.check(y, 'def', 'screen:1')
1032   y = y + Editor_state.line_height
1033   App.screen.check(y, 'ghi', 'screen:2')
1034 end
1035
1036 function test_pagedown_skips_drawings()
1037   -- some lines of text with a drawing intermixed
1038   local drawing_width = 50
1039   App.screen.init{width=Editor_state.left+drawing_width, height=80}
1040   Editor_state = edit.initialize_test_state()
1041   Editor_state.lines = load_array{'abc',               -- height 15
1042                                   '```lines', '```',   -- height 25
1043                                   'def',               -- height 15
1044                                   'ghi'}               -- height 15
1045   Text.redraw_all(Editor_state)
1046   check_eq(Editor_state.lines[2].mode, 'drawing', 'baseline/lines')
1047   Editor_state.cursor1 = {line=1, pos=1}
1048   Editor_state.screen_top1 = {line=1, pos=1}
1049   Editor_state.screen_bottom1 = {}
1050   local drawing_height = Drawing_padding_height + drawing_width/2  -- default
1051   -- initially the screen displays the first line and the drawing
1052   -- 15px margin + 15px line1 + 10px margin + 25px drawing + 10px margin = 75px < screen height 80px
1053   edit.draw(Editor_state)
1054   local y = Editor_state.top
1055   App.screen.check(y, 'abc', 'baseline/screen:1')
1056   -- after pagedown the screen draws the drawing up top
1057   -- 15px margin + 10px margin + 25px drawing + 10px margin + 15px line3 = 75px < screen height 80px
1058   edit.run_after_keychord(Editor_state, 'pagedown')
1059   check_eq(Editor_state.screen_top1.line, 2, 'screen_top')
1060   check_eq(Editor_state.cursor1.line, 3, 'cursor')
1061   y = Editor_state.top + drawing_height
1062   App.screen.check(y, 'def', 'screen:1')
1063 end
1064
1065 function test_pagedown_often_shows_start_of_wrapping_line()
1066   -- draw a few lines ending in part of a wrapping line
1067   App.screen.init{width=50, height=60}
1068   Editor_state = edit.initialize_test_state()
1069   Editor_state.lines = load_array{'abc', 'def ghi jkl', 'mno'}
1070   Text.redraw_all(Editor_state)
1071   Editor_state.cursor1 = {line=1, pos=1}
1072   Editor_state.screen_top1 = {line=1, pos=1}
1073   Editor_state.screen_bottom1 = {}
1074   edit.draw(Editor_state)
1075   local y = Editor_state.top
1076   App.screen.check(y, 'abc', 'baseline/screen:1')
1077   y = y + Editor_state.line_height
1078   App.screen.check(y, 'def ', 'baseline/screen:2')
1079   y = y + Editor_state.line_height
1080   App.screen.check(y, 'ghi ', 'baseline/screen:3')
1081   -- after pagedown we start drawing from the bottom _line_ (multiple screen lines)
1082   edit.run_after_keychord(Editor_state, 'pagedown')
1083   check_eq(Editor_state.screen_top1.line, 2, 'screen_top:line')
1084   check_eq(Editor_state.screen_top1.pos, 1, 'screen_top:pos')
1085   check_eq(Editor_state.cursor1.line, 2, 'cursor:line')
1086   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
1087   y = Editor_state.top
1088   App.screen.check(y, 'def ', 'screen:1')
1089   y = y + Editor_state.line_height
1090   App.screen.check(y, 'ghi ', 'screen:2')
1091   y = y + Editor_state.line_height
1092   App.screen.check(y, 'jkl', 'screen:3')
1093 end
1094
1095 function test_pagedown_can_start_from_middle_of_long_wrapping_line()
1096   -- draw a few lines starting from a very long wrapping line
1097   App.screen.init{width=Editor_state.left+30, height=60}
1098   Editor_state = edit.initialize_test_state()
1099   Editor_state.lines = load_array{'abc def ghi jkl mno pqr stu vwx yza bcd efg hij', 'XYZ'}
1100   Text.redraw_all(Editor_state)
1101   Editor_state.cursor1 = {line=1, pos=2}
1102   Editor_state.screen_top1 = {line=1, pos=1}
1103   Editor_state.screen_bottom1 = {}
1104   edit.draw(Editor_state)
1105   local y = Editor_state.top
1106   App.screen.check(y, 'abc ', 'baseline/screen:1')
1107   y = y + Editor_state.line_height
1108   App.screen.check(y, 'def ', 'baseline/screen:2')
1109   y = y + Editor_state.line_height
1110   App.screen.check(y, 'ghi ', 'baseline/screen:3')
1111   -- after pagedown we scroll down the very long wrapping line
1112   edit.run_after_keychord(Editor_state, 'pagedown')
1113   check_eq(Editor_state.screen_top1.line, 1, 'screen_top:line')
1114   check_eq(Editor_state.screen_top1.pos, 9, 'screen_top:pos')
1115   y = Editor_state.top
1116   App.screen.check(y, 'ghi ', 'screen:1')
1117   y = y + Editor_state.line_height
1118   App.screen.check(y, 'jkl ', 'screen:2')
1119   y = y + Editor_state.line_height
1120   if Version == '12.0' then
1121     -- HACK: Maybe v12.0 uses a different font? Strange that it only causes
1122     -- issues in a couple of places.
1123     -- We'll need to rethink our tests if issues like this start to multiply.
1124     App.screen.check(y, 'mno ', 'screen:3')
1125   else
1126     App.screen.check(y, 'mn', 'screen:3')
1127   end
1128 end
1129
1130 function test_pagedown_never_moves_up()
1131   -- draw the final screen line of a wrapping line
1132   App.screen.init{width=Editor_state.left+30, height=60}
1133   Editor_state = edit.initialize_test_state()
1134   Editor_state.lines = load_array{'abc def ghi'}
1135   Text.redraw_all(Editor_state)
1136   Editor_state.cursor1 = {line=1, pos=9}
1137   Editor_state.screen_top1 = {line=1, pos=9}
1138   Editor_state.screen_bottom1 = {}
1139   edit.draw(Editor_state)
1140   -- pagedown makes no change
1141   edit.run_after_keychord(Editor_state, 'pagedown')
1142   check_eq(Editor_state.screen_top1.line, 1, 'screen_top:line')
1143   check_eq(Editor_state.screen_top1.pos, 9, 'screen_top:pos')
1144 end
1145
1146 function test_down_arrow_moves_cursor()
1147   App.screen.init{width=120, height=60}
1148   Editor_state = edit.initialize_test_state()
1149   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
1150   Text.redraw_all(Editor_state)
1151   Editor_state.cursor1 = {line=1, pos=1}
1152   Editor_state.screen_top1 = {line=1, pos=1}
1153   Editor_state.screen_bottom1 = {}
1154   -- initially the first three lines are displayed
1155   edit.draw(Editor_state)
1156   local y = Editor_state.top
1157   App.screen.check(y, 'abc', 'baseline/screen:1')
1158   y = y + Editor_state.line_height
1159   App.screen.check(y, 'def', 'baseline/screen:2')
1160   y = y + Editor_state.line_height
1161   App.screen.check(y, 'ghi', 'baseline/screen:3')
1162   -- after hitting the down arrow, the cursor moves down by 1 line
1163   edit.run_after_keychord(Editor_state, 'down')
1164   check_eq(Editor_state.screen_top1.line, 1, 'screen_top')
1165   check_eq(Editor_state.cursor1.line, 2, 'cursor')
1166   -- the screen is unchanged
1167   y = Editor_state.top
1168   App.screen.check(y, 'abc', 'screen:1')
1169   y = y + Editor_state.line_height
1170   App.screen.check(y, 'def', 'screen:2')
1171   y = y + Editor_state.line_height
1172   App.screen.check(y, 'ghi', 'screen:3')
1173 end
1174
1175 function test_down_arrow_skips_drawing()
1176   -- some lines of text with a drawing intermixed
1177   local drawing_width = 50
1178   App.screen.init{width=Editor_state.left+drawing_width, height=100}
1179   Editor_state = edit.initialize_test_state()
1180   Editor_state.lines = load_array{'abc',               -- height 15
1181                                   '```lines', '```',   -- height 25
1182                                   'ghi'}
1183   Text.redraw_all(Editor_state)
1184   Editor_state.cursor1 = {line=1, pos=1}
1185   Editor_state.screen_top1 = {line=1, pos=1}
1186   Editor_state.screen_bottom1 = {}
1187   edit.draw(Editor_state)
1188   local y = Editor_state.top
1189   App.screen.check(y, 'abc', 'baseline/screen:1')
1190   y = y + Editor_state.line_height
1191   local drawing_height = Drawing_padding_height + drawing_width/2  -- default
1192   y = y + drawing_height
1193   App.screen.check(y, 'ghi', 'baseline/screen:3')
1194   check(Editor_state.cursor_x, 'baseline/cursor_x')
1195   -- after hitting the down arrow the cursor moves down by 2 lines, skipping the drawing
1196   edit.run_after_keychord(Editor_state, 'down')
1197   check_eq(Editor_state.cursor1.line, 3, 'cursor')
1198 end
1199
1200 function test_down_arrow_scrolls_down_by_one_line()
1201   -- display the first three lines with the cursor on the bottom line
1202   App.screen.init{width=120, height=60}
1203   Editor_state = edit.initialize_test_state()
1204   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
1205   Text.redraw_all(Editor_state)
1206   Editor_state.cursor1 = {line=3, pos=1}
1207   Editor_state.screen_top1 = {line=1, pos=1}
1208   Editor_state.screen_bottom1 = {}
1209   edit.draw(Editor_state)
1210   local y = Editor_state.top
1211   App.screen.check(y, 'abc', 'baseline/screen:1')
1212   y = y + Editor_state.line_height
1213   App.screen.check(y, 'def', 'baseline/screen:2')
1214   y = y + Editor_state.line_height
1215   App.screen.check(y, 'ghi', 'baseline/screen:3')
1216   -- after hitting the down arrow the screen scrolls down by one line
1217   edit.run_after_keychord(Editor_state, 'down')
1218   check_eq(Editor_state.screen_top1.line, 2, 'screen_top')
1219   check_eq(Editor_state.cursor1.line, 4, 'cursor')
1220   y = Editor_state.top
1221   App.screen.check(y, 'def', 'screen:1')
1222   y = y + Editor_state.line_height
1223   App.screen.check(y, 'ghi', 'screen:2')
1224   y = y + Editor_state.line_height
1225   App.screen.check(y, 'jkl', 'screen:3')
1226 end
1227
1228 function test_down_arrow_scrolls_down_by_one_screen_line()
1229   -- display the first three lines with the cursor on the bottom line
1230   App.screen.init{width=Editor_state.left+30, height=60}
1231   Editor_state = edit.initialize_test_state()
1232   Editor_state.lines = load_array{'abc', 'def', 'ghi jkl', 'mno'}
1233   Text.redraw_all(Editor_state)
1234   Editor_state.cursor1 = {line=3, pos=1}
1235   Editor_state.screen_top1 = {line=1, pos=1}
1236   Editor_state.screen_bottom1 = {}
1237   edit.draw(Editor_state)
1238   local y = Editor_state.top
1239   App.screen.check(y, 'abc', 'baseline/screen:1')
1240   y = y + Editor_state.line_height
1241   App.screen.check(y, 'def', 'baseline/screen:2')
1242   y = y + Editor_state.line_height
1243   App.screen.check(y, 'ghi ', 'baseline/screen:3')  -- line wrapping includes trailing whitespace
1244   -- after hitting the down arrow the screen scrolls down by one line
1245   edit.run_after_keychord(Editor_state, 'down')
1246   check_eq(Editor_state.screen_top1.line, 2, 'screen_top')
1247   check_eq(Editor_state.cursor1.line, 3, 'cursor:line')
1248   check_eq(Editor_state.cursor1.pos, 5, 'cursor:pos')
1249   y = Editor_state.top
1250   App.screen.check(y, 'def', 'screen:1')
1251   y = y + Editor_state.line_height
1252   App.screen.check(y, 'ghi ', 'screen:2')
1253   y = y + Editor_state.line_height
1254   App.screen.check(y, 'jkl', 'screen:3')
1255 end
1256
1257 function test_down_arrow_scrolls_down_by_one_screen_line_after_splitting_within_word()
1258   -- display the first three lines with the cursor on the bottom line
1259   App.screen.init{width=Editor_state.left+30, height=60}
1260   Editor_state = edit.initialize_test_state()
1261   Editor_state.lines = load_array{'abc', 'def', 'ghijkl', 'mno'}
1262   Text.redraw_all(Editor_state)
1263   Editor_state.cursor1 = {line=3, pos=1}
1264   Editor_state.screen_top1 = {line=1, pos=1}
1265   Editor_state.screen_bottom1 = {}
1266   edit.draw(Editor_state)
1267   local y = Editor_state.top
1268   App.screen.check(y, 'abc', 'baseline/screen:1')
1269   y = y + Editor_state.line_height
1270   App.screen.check(y, 'def', 'baseline/screen:2')
1271   y = y + Editor_state.line_height
1272   App.screen.check(y, 'ghij', 'baseline/screen:3')
1273   -- after hitting the down arrow the screen scrolls down by one line
1274   edit.run_after_keychord(Editor_state, 'down')
1275   check_eq(Editor_state.screen_top1.line, 2, 'screen_top')
1276   check_eq(Editor_state.cursor1.line, 3, 'cursor:line')
1277   check_eq(Editor_state.cursor1.pos, 5, 'cursor:pos')
1278   y = Editor_state.top
1279   App.screen.check(y, 'def', 'screen:1')
1280   y = y + Editor_state.line_height
1281   App.screen.check(y, 'ghij', 'screen:2')
1282   y = y + Editor_state.line_height
1283   App.screen.check(y, 'kl', 'screen:3')
1284 end
1285
1286 function test_pagedown_followed_by_down_arrow_does_not_scroll_screen_up()
1287   App.screen.init{width=Editor_state.left+30, height=60}
1288   Editor_state = edit.initialize_test_state()
1289   Editor_state.lines = load_array{'abc', 'def', 'ghijkl', 'mno'}
1290   Text.redraw_all(Editor_state)
1291   Editor_state.cursor1 = {line=3, pos=1}
1292   Editor_state.screen_top1 = {line=1, pos=1}
1293   Editor_state.screen_bottom1 = {}
1294   edit.draw(Editor_state)
1295   local y = Editor_state.top
1296   App.screen.check(y, 'abc', 'baseline/screen:1')
1297   y = y + Editor_state.line_height
1298   App.screen.check(y, 'def', 'baseline/screen:2')
1299   y = y + Editor_state.line_height
1300   App.screen.check(y, 'ghij', 'baseline/screen:3')
1301   -- after hitting pagedown the screen scrolls down to start of a long line
1302   edit.run_after_keychord(Editor_state, 'pagedown')
1303   check_eq(Editor_state.screen_top1.line, 3, 'baseline2/screen_top')
1304   check_eq(Editor_state.cursor1.line, 3, 'baseline2/cursor:line')
1305   check_eq(Editor_state.cursor1.pos, 1, 'baseline2/cursor:pos')
1306   -- after hitting down arrow the screen doesn't scroll down further, and certainly doesn't scroll up
1307   edit.run_after_keychord(Editor_state, 'down')
1308   check_eq(Editor_state.screen_top1.line, 3, 'screen_top')
1309   check_eq(Editor_state.cursor1.line, 3, 'cursor:line')
1310   check_eq(Editor_state.cursor1.pos, 5, 'cursor:pos')
1311   y = Editor_state.top
1312   App.screen.check(y, 'ghij', 'screen:1')
1313   y = y + Editor_state.line_height
1314   App.screen.check(y, 'kl', 'screen:2')
1315   y = y + Editor_state.line_height
1316   App.screen.check(y, 'mno', 'screen:3')
1317 end
1318
1319 function test_up_arrow_moves_cursor()
1320   -- display the first 3 lines with the cursor on the bottom line
1321   App.screen.init{width=120, height=60}
1322   Editor_state = edit.initialize_test_state()
1323   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
1324   Text.redraw_all(Editor_state)
1325   Editor_state.cursor1 = {line=3, pos=1}
1326   Editor_state.screen_top1 = {line=1, pos=1}
1327   Editor_state.screen_bottom1 = {}
1328   edit.draw(Editor_state)
1329   local y = Editor_state.top
1330   App.screen.check(y, 'abc', 'baseline/screen:1')
1331   y = y + Editor_state.line_height
1332   App.screen.check(y, 'def', 'baseline/screen:2')
1333   y = y + Editor_state.line_height
1334   App.screen.check(y, 'ghi', 'baseline/screen:3')
1335   -- after hitting the up arrow the cursor moves up by 1 line
1336   edit.run_after_keychord(Editor_state, 'up')
1337   check_eq(Editor_state.screen_top1.line, 1, 'screen_top')
1338   check_eq(Editor_state.cursor1.line, 2, 'cursor')
1339   -- the screen is unchanged
1340   y = Editor_state.top
1341   App.screen.check(y, 'abc', 'screen:1')
1342   y = y + Editor_state.line_height
1343   App.screen.check(y, 'def', 'screen:2')
1344   y = y + Editor_state.line_height
1345   App.screen.check(y, 'ghi', 'screen:3')
1346 end
1347
1348 function test_up_arrow_skips_drawing()
1349   -- some lines of text with a drawing intermixed
1350   local drawing_width = 50
1351   App.screen.init{width=Editor_state.left+drawing_width, height=100}
1352   Editor_state = edit.initialize_test_state()
1353   Editor_state.lines = load_array{'abc',               -- height 15
1354                                   '```lines', '```',   -- height 25
1355                                   'ghi'}
1356   Text.redraw_all(Editor_state)
1357   Editor_state.cursor1 = {line=3, pos=1}
1358   Editor_state.screen_top1 = {line=1, pos=1}
1359   Editor_state.screen_bottom1 = {}
1360   edit.draw(Editor_state)
1361   local y = Editor_state.top
1362   App.screen.check(y, 'abc', 'baseline/screen:1')
1363   y = y + Editor_state.line_height
1364   local drawing_height = Drawing_padding_height + drawing_width/2  -- default
1365   y = y + drawing_height
1366   App.screen.check(y, 'ghi', 'baseline/screen:3')
1367   check(Editor_state.cursor_x, 'baseline/cursor_x')
1368   -- after hitting the up arrow the cursor moves up by 2 lines, skipping the drawing
1369   edit.run_after_keychord(Editor_state, 'up')
1370   check_eq(Editor_state.cursor1.line, 1, 'cursor')
1371 end
1372
1373 function test_up_arrow_scrolls_up_by_one_line()
1374   -- display the lines 2/3/4 with the cursor on line 2
1375   App.screen.init{width=120, height=60}
1376   Editor_state = edit.initialize_test_state()
1377   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
1378   Text.redraw_all(Editor_state)
1379   Editor_state.cursor1 = {line=2, pos=1}
1380   Editor_state.screen_top1 = {line=2, pos=1}
1381   Editor_state.screen_bottom1 = {}
1382   edit.draw(Editor_state)
1383   local y = Editor_state.top
1384   App.screen.check(y, 'def', 'baseline/screen:1')
1385   y = y + Editor_state.line_height
1386   App.screen.check(y, 'ghi', 'baseline/screen:2')
1387   y = y + Editor_state.line_height
1388   App.screen.check(y, 'jkl', 'baseline/screen:3')
1389   -- after hitting the up arrow the screen scrolls up by one line
1390   edit.run_after_keychord(Editor_state, 'up')
1391   check_eq(Editor_state.screen_top1.line, 1, 'screen_top')
1392   check_eq(Editor_state.cursor1.line, 1, 'cursor')
1393   y = Editor_state.top
1394   App.screen.check(y, 'abc', 'screen:1')
1395   y = y + Editor_state.line_height
1396   App.screen.check(y, 'def', 'screen:2')
1397   y = y + Editor_state.line_height
1398   App.screen.check(y, 'ghi', 'screen:3')
1399 end
1400
1401 function test_up_arrow_scrolls_up_by_one_line_skipping_drawing()
1402   -- display lines 3/4/5 with a drawing just off screen at line 2
1403   App.screen.init{width=120, height=60}
1404   Editor_state = edit.initialize_test_state()
1405   Editor_state.lines = load_array{'abc', '```lines', '```', 'def', 'ghi', 'jkl'}
1406   Text.redraw_all(Editor_state)
1407   Editor_state.cursor1 = {line=3, pos=1}
1408   Editor_state.screen_top1 = {line=3, pos=1}
1409   Editor_state.screen_bottom1 = {}
1410   edit.draw(Editor_state)
1411   local y = Editor_state.top
1412   App.screen.check(y, 'def', 'baseline/screen:1')
1413   y = y + Editor_state.line_height
1414   App.screen.check(y, 'ghi', 'baseline/screen:2')
1415   y = y + Editor_state.line_height
1416   App.screen.check(y, 'jkl', 'baseline/screen:3')
1417   -- after hitting the up arrow the screen scrolls up to previous text line
1418   edit.run_after_keychord(Editor_state, 'up')
1419   check_eq(Editor_state.screen_top1.line, 1, 'screen_top')
1420   check_eq(Editor_state.cursor1.line, 1, 'cursor')
1421 end
1422
1423 function test_up_arrow_scrolls_up_by_one_screen_line()
1424   -- display lines starting from second screen line of a line
1425   App.screen.init{width=Editor_state.left+30, height=60}
1426   Editor_state = edit.initialize_test_state()
1427   Editor_state.lines = load_array{'abc', 'def', 'ghi jkl', 'mno'}
1428   Text.redraw_all(Editor_state)
1429   Editor_state.cursor1 = {line=3, pos=6}
1430   Editor_state.screen_top1 = {line=3, pos=5}
1431   Editor_state.screen_bottom1 = {}
1432   edit.draw(Editor_state)
1433   local y = Editor_state.top
1434   App.screen.check(y, 'jkl', 'baseline/screen:1')
1435   y = y + Editor_state.line_height
1436   App.screen.check(y, 'mno', 'baseline/screen:2')
1437   -- after hitting the up arrow the screen scrolls up to first screen line
1438   edit.run_after_keychord(Editor_state, 'up')
1439   y = Editor_state.top
1440   App.screen.check(y, 'ghi ', 'screen:1')
1441   y = y + Editor_state.line_height
1442   App.screen.check(y, 'jkl', 'screen:2')
1443   y = y + Editor_state.line_height
1444   App.screen.check(y, 'mno', 'screen:3')
1445   check_eq(Editor_state.screen_top1.line, 3, 'screen_top:line')
1446   check_eq(Editor_state.screen_top1.pos, 1, 'screen_top:pos')
1447   check_eq(Editor_state.cursor1.line, 3, 'cursor:line')
1448   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
1449 end
1450
1451 function test_up_arrow_scrolls_up_to_final_screen_line()
1452   -- display lines starting just after a long line
1453   App.screen.init{width=Editor_state.left+30, height=60}
1454   Editor_state = edit.initialize_test_state()
1455   Editor_state.lines = load_array{'abc def', 'ghi', 'jkl', 'mno'}
1456   Text.redraw_all(Editor_state)
1457   Editor_state.cursor1 = {line=2, pos=1}
1458   Editor_state.screen_top1 = {line=2, pos=1}
1459   Editor_state.screen_bottom1 = {}
1460   edit.draw(Editor_state)
1461   local y = Editor_state.top
1462   App.screen.check(y, 'ghi', 'baseline/screen:1')
1463   y = y + Editor_state.line_height
1464   App.screen.check(y, 'jkl', 'baseline/screen:2')
1465   y = y + Editor_state.line_height
1466   App.screen.check(y, 'mno', 'baseline/screen:3')
1467   -- after hitting the up arrow the screen scrolls up to final screen line of previous line
1468   edit.run_after_keychord(Editor_state, 'up')
1469   y = Editor_state.top
1470   App.screen.check(y, 'def', 'screen:1')
1471   y = y + Editor_state.line_height
1472   App.screen.check(y, 'ghi', 'screen:2')
1473   y = y + Editor_state.line_height
1474   App.screen.check(y, 'jkl', 'screen:3')
1475   check_eq(Editor_state.screen_top1.line, 1, 'screen_top:line')
1476   check_eq(Editor_state.screen_top1.pos, 5, 'screen_top:pos')
1477   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
1478   check_eq(Editor_state.cursor1.pos, 5, 'cursor:pos')
1479 end
1480
1481 function test_up_arrow_scrolls_up_to_empty_line()
1482   -- display a screenful of text with an empty line just above it outside the screen
1483   App.screen.init{width=120, height=60}
1484   Editor_state = edit.initialize_test_state()
1485   Editor_state.lines = load_array{'', 'abc', 'def', 'ghi', 'jkl'}
1486   Text.redraw_all(Editor_state)
1487   Editor_state.cursor1 = {line=2, pos=1}
1488   Editor_state.screen_top1 = {line=2, pos=1}
1489   Editor_state.screen_bottom1 = {}
1490   edit.draw(Editor_state)
1491   local y = Editor_state.top
1492   App.screen.check(y, 'abc', 'baseline/screen:1')
1493   y = y + Editor_state.line_height
1494   App.screen.check(y, 'def', 'baseline/screen:2')
1495   y = y + Editor_state.line_height
1496   App.screen.check(y, 'ghi', 'baseline/screen:3')
1497   -- after hitting the up arrow the screen scrolls up by one line
1498   edit.run_after_keychord(Editor_state, 'up')
1499   check_eq(Editor_state.screen_top1.line, 1, 'screen_top')
1500   check_eq(Editor_state.cursor1.line, 1, 'cursor')
1501   y = Editor_state.top
1502   -- empty first line
1503   y = y + Editor_state.line_height
1504   App.screen.check(y, 'abc', 'screen:2')
1505   y = y + Editor_state.line_height
1506   App.screen.check(y, 'def', 'screen:3')
1507 end
1508
1509 function test_pageup()
1510   App.screen.init{width=120, height=45}
1511   Editor_state = edit.initialize_test_state()
1512   Editor_state.lines = load_array{'abc', 'def', 'ghi'}
1513   Text.redraw_all(Editor_state)
1514   Editor_state.cursor1 = {line=2, pos=1}
1515   Editor_state.screen_top1 = {line=2, pos=1}
1516   Editor_state.screen_bottom1 = {}
1517   -- initially the last two lines are displayed
1518   edit.draw(Editor_state)
1519   local y = Editor_state.top
1520   App.screen.check(y, 'def', 'baseline/screen:1')
1521   y = y + Editor_state.line_height
1522   App.screen.check(y, 'ghi', 'baseline/screen:2')
1523   -- after pageup the cursor goes to first line
1524   edit.run_after_keychord(Editor_state, 'pageup')
1525   check_eq(Editor_state.screen_top1.line, 1, 'screen_top')
1526   check_eq(Editor_state.cursor1.line, 1, 'cursor')
1527   y = Editor_state.top
1528   App.screen.check(y, 'abc', 'screen:1')
1529   y = y + Editor_state.line_height
1530   App.screen.check(y, 'def', 'screen:2')
1531 end
1532
1533 function test_pageup_scrolls_up_by_screen_line()
1534   -- display the first three lines with the cursor on the bottom line
1535   App.screen.init{width=Editor_state.left+30, height=60}
1536   Editor_state = edit.initialize_test_state()
1537   Editor_state.lines = load_array{'abc def', 'ghi', 'jkl', 'mno'}
1538   Text.redraw_all(Editor_state)
1539   Editor_state.cursor1 = {line=2, pos=1}
1540   Editor_state.screen_top1 = {line=2, pos=1}
1541   Editor_state.screen_bottom1 = {}
1542   edit.draw(Editor_state)
1543   local y = Editor_state.top
1544   App.screen.check(y, 'ghi', 'baseline/screen:1')
1545   y = y + Editor_state.line_height
1546   App.screen.check(y, 'jkl', 'baseline/screen:2')
1547   y = y + Editor_state.line_height
1548   App.screen.check(y, 'mno', 'baseline/screen:3')  -- line wrapping includes trailing whitespace
1549   -- after hitting the page-up key the screen scrolls up to top
1550   edit.run_after_keychord(Editor_state, 'pageup')
1551   check_eq(Editor_state.screen_top1.line, 1, 'screen_top')
1552   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
1553   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
1554   y = Editor_state.top
1555   App.screen.check(y, 'abc ', 'screen:1')
1556   y = y + Editor_state.line_height
1557   App.screen.check(y, 'def', 'screen:2')
1558   y = y + Editor_state.line_height
1559   App.screen.check(y, 'ghi', 'screen:3')
1560 end
1561
1562 function test_pageup_scrolls_up_from_middle_screen_line()
1563   -- display a few lines starting from the middle of a line (Editor_state.cursor1.pos > 1)
1564   App.screen.init{width=Editor_state.left+30, height=60}
1565   Editor_state = edit.initialize_test_state()
1566   Editor_state.lines = load_array{'abc def', 'ghi jkl', 'mno'}
1567   Text.redraw_all(Editor_state)
1568   Editor_state.cursor1 = {line=2, pos=5}
1569   Editor_state.screen_top1 = {line=2, pos=5}
1570   Editor_state.screen_bottom1 = {}
1571   edit.draw(Editor_state)
1572   local y = Editor_state.top
1573   App.screen.check(y, 'jkl', 'baseline/screen:2')
1574   y = y + Editor_state.line_height
1575   App.screen.check(y, 'mno', 'baseline/screen:3')  -- line wrapping includes trailing whitespace
1576   -- after hitting the page-up key the screen scrolls up to top
1577   edit.run_after_keychord(Editor_state, 'pageup')
1578   check_eq(Editor_state.screen_top1.line, 1, 'screen_top')
1579   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
1580   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
1581   y = Editor_state.top
1582   App.screen.check(y, 'abc ', 'screen:1')
1583   y = y + Editor_state.line_height
1584   App.screen.check(y, 'def', 'screen:2')
1585   y = y + Editor_state.line_height
1586   App.screen.check(y, 'ghi ', 'screen:3')
1587 end
1588
1589 function test_enter_on_bottom_line_scrolls_down()
1590   -- display a few lines with cursor on bottom line
1591   App.screen.init{width=Editor_state.left+30, height=60}
1592   Editor_state = edit.initialize_test_state()
1593   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
1594   Text.redraw_all(Editor_state)
1595   Editor_state.cursor1 = {line=3, pos=2}
1596   Editor_state.screen_top1 = {line=1, pos=1}
1597   Editor_state.screen_bottom1 = {}
1598   edit.draw(Editor_state)
1599   local y = Editor_state.top
1600   App.screen.check(y, 'abc', 'baseline/screen:1')
1601   y = y + Editor_state.line_height
1602   App.screen.check(y, 'def', 'baseline/screen:2')
1603   y = y + Editor_state.line_height
1604   App.screen.check(y, 'ghi', 'baseline/screen:3')
1605   -- after hitting the enter key the screen scrolls down
1606   edit.run_after_keychord(Editor_state, 'return')
1607   check_eq(Editor_state.screen_top1.line, 2, 'screen_top')
1608   check_eq(Editor_state.cursor1.line, 4, 'cursor:line')
1609   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
1610   y = Editor_state.top
1611   App.screen.check(y, 'def', 'screen:1')
1612   y = y + Editor_state.line_height
1613   App.screen.check(y, 'g', 'screen:2')
1614   y = y + Editor_state.line_height
1615   App.screen.check(y, 'hi', 'screen:3')
1616 end
1617
1618 function test_enter_on_final_line_avoids_scrolling_down_when_not_at_bottom()
1619   -- display just the bottom line on screen
1620   App.screen.init{width=Editor_state.left+30, height=60}
1621   Editor_state = edit.initialize_test_state()
1622   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
1623   Text.redraw_all(Editor_state)
1624   Editor_state.cursor1 = {line=4, pos=2}
1625   Editor_state.screen_top1 = {line=4, pos=1}
1626   Editor_state.screen_bottom1 = {}
1627   edit.draw(Editor_state)
1628   local y = Editor_state.top
1629   App.screen.check(y, 'jkl', 'baseline/screen:1')
1630   -- after hitting the enter key the screen does not scroll down
1631   edit.run_after_keychord(Editor_state, 'return')
1632   check_eq(Editor_state.screen_top1.line, 4, 'screen_top')
1633   check_eq(Editor_state.cursor1.line, 5, 'cursor:line')
1634   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
1635   y = Editor_state.top
1636   App.screen.check(y, 'j', 'screen:1')
1637   y = y + Editor_state.line_height
1638   App.screen.check(y, 'kl', 'screen:2')
1639 end
1640
1641 function test_inserting_text_on_final_line_avoids_scrolling_down_when_not_at_bottom()
1642   -- display just an empty bottom line on screen
1643   App.screen.init{width=Editor_state.left+30, height=60}
1644   Editor_state = edit.initialize_test_state()
1645   Editor_state.lines = load_array{'abc', ''}
1646   Text.redraw_all(Editor_state)
1647   Editor_state.cursor1 = {line=2, pos=1}
1648   Editor_state.screen_top1 = {line=2, pos=1}
1649   Editor_state.screen_bottom1 = {}
1650   edit.draw(Editor_state)
1651   -- after hitting the inserting_text key the screen does not scroll down
1652   edit.run_after_text_input(Editor_state, 'a')
1653   check_eq(Editor_state.screen_top1.line, 2, 'screen_top')
1654   check_eq(Editor_state.cursor1.line, 2, 'cursor:line')
1655   check_eq(Editor_state.cursor1.pos, 2, 'cursor:pos')
1656   local y = Editor_state.top
1657   App.screen.check(y, 'a', 'screen:1')
1658 end
1659
1660 function test_typing_on_bottom_line_scrolls_down()
1661   -- display a few lines with cursor on bottom line
1662   App.screen.init{width=Editor_state.left+30, height=60}
1663   Editor_state = edit.initialize_test_state()
1664   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
1665   Text.redraw_all(Editor_state)
1666   Editor_state.cursor1 = {line=3, pos=4}
1667   Editor_state.screen_top1 = {line=1, pos=1}
1668   Editor_state.screen_bottom1 = {}
1669   edit.draw(Editor_state)
1670   local y = Editor_state.top
1671   App.screen.check(y, 'abc', 'baseline/screen:1')
1672   y = y + Editor_state.line_height
1673   App.screen.check(y, 'def', 'baseline/screen:2')
1674   y = y + Editor_state.line_height
1675   App.screen.check(y, 'ghi', 'baseline/screen:3')
1676   -- after typing something the line wraps and the screen scrolls down
1677   edit.run_after_text_input(Editor_state, 'j')
1678   edit.run_after_text_input(Editor_state, 'k')
1679   edit.run_after_text_input(Editor_state, 'l')
1680   check_eq(Editor_state.screen_top1.line, 2, 'screen_top')
1681   check_eq(Editor_state.cursor1.line, 3, 'cursor:line')
1682   check_eq(Editor_state.cursor1.pos, 7, 'cursor:pos')
1683   y = Editor_state.top
1684   App.screen.check(y, 'def', 'screen:1')
1685   y = y + Editor_state.line_height
1686   App.screen.check(y, 'ghij', 'screen:2')
1687   y = y + Editor_state.line_height
1688   App.screen.check(y, 'kl', 'screen:3')
1689 end
1690
1691 function test_left_arrow_scrolls_up_in_wrapped_line()
1692   -- display lines starting from second screen line of a line
1693   App.screen.init{width=Editor_state.left+30, height=60}
1694   Editor_state = edit.initialize_test_state()
1695   Editor_state.lines = load_array{'abc', 'def', 'ghi jkl', 'mno'}
1696   Text.redraw_all(Editor_state)
1697   Editor_state.screen_top1 = {line=3, pos=5}
1698   Editor_state.screen_bottom1 = {}
1699   -- cursor is at top of screen
1700   Editor_state.cursor1 = {line=3, pos=5}
1701   edit.draw(Editor_state)
1702   local y = Editor_state.top
1703   App.screen.check(y, 'jkl', 'baseline/screen:1')
1704   y = y + Editor_state.line_height
1705   App.screen.check(y, 'mno', 'baseline/screen:2')
1706   -- after hitting the left arrow the screen scrolls up to first screen line
1707   edit.run_after_keychord(Editor_state, 'left')
1708   y = Editor_state.top
1709   App.screen.check(y, 'ghi ', 'screen:1')
1710   y = y + Editor_state.line_height
1711   App.screen.check(y, 'jkl', 'screen:2')
1712   y = y + Editor_state.line_height
1713   App.screen.check(y, 'mno', 'screen:3')
1714   check_eq(Editor_state.screen_top1.line, 3, 'screen_top:line')
1715   check_eq(Editor_state.screen_top1.pos, 1, 'screen_top:pos')
1716   check_eq(Editor_state.cursor1.line, 3, 'cursor:line')
1717   check_eq(Editor_state.cursor1.pos, 4, 'cursor:pos')
1718 end
1719
1720 function test_right_arrow_scrolls_down_in_wrapped_line()
1721   -- display the first three lines with the cursor on the bottom line
1722   App.screen.init{width=Editor_state.left+30, height=60}
1723   Editor_state = edit.initialize_test_state()
1724   Editor_state.lines = load_array{'abc', 'def', 'ghi jkl', 'mno'}
1725   Text.redraw_all(Editor_state)
1726   Editor_state.screen_top1 = {line=1, pos=1}
1727   Editor_state.screen_bottom1 = {}
1728   -- cursor is at bottom right of screen
1729   Editor_state.cursor1 = {line=3, pos=5}
1730   edit.draw(Editor_state)
1731   local y = Editor_state.top
1732   App.screen.check(y, 'abc', 'baseline/screen:1')
1733   y = y + Editor_state.line_height
1734   App.screen.check(y, 'def', 'baseline/screen:2')
1735   y = y + Editor_state.line_height
1736   App.screen.check(y, 'ghi ', 'baseline/screen:3')  -- line wrapping includes trailing whitespace
1737   -- after hitting the right arrow the screen scrolls down by one line
1738   edit.run_after_keychord(Editor_state, 'right')
1739   check_eq(Editor_state.screen_top1.line, 2, 'screen_top')
1740   check_eq(Editor_state.cursor1.line, 3, 'cursor:line')
1741   check_eq(Editor_state.cursor1.pos, 6, 'cursor:pos')
1742   y = Editor_state.top
1743   App.screen.check(y, 'def', 'screen:1')
1744   y = y + Editor_state.line_height
1745   App.screen.check(y, 'ghi ', 'screen:2')
1746   y = y + Editor_state.line_height
1747   App.screen.check(y, 'jkl', 'screen:3')
1748 end
1749
1750 function test_home_scrolls_up_in_wrapped_line()
1751   -- display lines starting from second screen line of a line
1752   App.screen.init{width=Editor_state.left+30, height=60}
1753   Editor_state = edit.initialize_test_state()
1754   Editor_state.lines = load_array{'abc', 'def', 'ghi jkl', 'mno'}
1755   Text.redraw_all(Editor_state)
1756   Editor_state.screen_top1 = {line=3, pos=5}
1757   Editor_state.screen_bottom1 = {}
1758   -- cursor is at top of screen
1759   Editor_state.cursor1 = {line=3, pos=5}
1760   edit.draw(Editor_state)
1761   local y = Editor_state.top
1762   App.screen.check(y, 'jkl', 'baseline/screen:1')
1763   y = y + Editor_state.line_height
1764   App.screen.check(y, 'mno', 'baseline/screen:2')
1765   -- after hitting home the screen scrolls up to first screen line
1766   edit.run_after_keychord(Editor_state, 'home')
1767   y = Editor_state.top
1768   App.screen.check(y, 'ghi ', 'screen:1')
1769   y = y + Editor_state.line_height
1770   App.screen.check(y, 'jkl', 'screen:2')
1771   y = y + Editor_state.line_height
1772   App.screen.check(y, 'mno', 'screen:3')
1773   check_eq(Editor_state.screen_top1.line, 3, 'screen_top:line')
1774   check_eq(Editor_state.screen_top1.pos, 1, 'screen_top:pos')
1775   check_eq(Editor_state.cursor1.line, 3, 'cursor:line')
1776   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
1777 end
1778
1779 function test_end_scrolls_down_in_wrapped_line()
1780   -- display the first three lines with the cursor on the bottom line
1781   App.screen.init{width=Editor_state.left+30, height=60}
1782   Editor_state = edit.initialize_test_state()
1783   Editor_state.lines = load_array{'abc', 'def', 'ghi jkl', 'mno'}
1784   Text.redraw_all(Editor_state)
1785   Editor_state.screen_top1 = {line=1, pos=1}
1786   Editor_state.screen_bottom1 = {}
1787   -- cursor is at bottom right of screen
1788   Editor_state.cursor1 = {line=3, pos=5}
1789   edit.draw(Editor_state)
1790   local y = Editor_state.top
1791   App.screen.check(y, 'abc', 'baseline/screen:1')
1792   y = y + Editor_state.line_height
1793   App.screen.check(y, 'def', 'baseline/screen:2')
1794   y = y + Editor_state.line_height
1795   App.screen.check(y, 'ghi ', 'baseline/screen:3')  -- line wrapping includes trailing whitespace
1796   -- after hitting end the screen scrolls down by one line
1797   edit.run_after_keychord(Editor_state, 'end')
1798   check_eq(Editor_state.screen_top1.line, 2, 'screen_top')
1799   check_eq(Editor_state.cursor1.line, 3, 'cursor:line')
1800   check_eq(Editor_state.cursor1.pos, 8, 'cursor:pos')
1801   y = Editor_state.top
1802   App.screen.check(y, 'def', 'screen:1')
1803   y = y + Editor_state.line_height
1804   App.screen.check(y, 'ghi ', 'screen:2')
1805   y = y + Editor_state.line_height
1806   App.screen.check(y, 'jkl', 'screen:3')
1807 end
1808
1809 function test_position_cursor_on_recently_edited_wrapping_line()
1810   -- draw a line wrapping over 2 screen lines
1811   App.screen.init{width=100, height=200}
1812   Editor_state = edit.initialize_test_state()
1813   Editor_state.lines = load_array{'abc def ghi jkl mno pqr ', 'xyz'}
1814   Text.redraw_all(Editor_state)
1815   Editor_state.cursor1 = {line=1, pos=25}
1816   Editor_state.screen_top1 = {line=1, pos=1}
1817   Editor_state.screen_bottom1 = {}
1818   edit.draw(Editor_state)
1819   local y = Editor_state.top
1820   App.screen.check(y, 'abc def ghi ', 'baseline1/screen:1')
1821   y = y + Editor_state.line_height
1822   App.screen.check(y, 'jkl mno pqr ', 'baseline1/screen:2')
1823   y = y + Editor_state.line_height
1824   App.screen.check(y, 'xyz', 'baseline1/screen:3')
1825   -- add to the line until it's wrapping over 3 screen lines
1826   edit.run_after_text_input(Editor_state, 's')
1827   edit.run_after_text_input(Editor_state, 't')
1828   edit.run_after_text_input(Editor_state, 'u')
1829   check_eq(Editor_state.cursor1.pos, 28, 'cursor:pos')
1830   y = Editor_state.top
1831   App.screen.check(y, 'abc def ghi ', 'baseline2/screen:1')
1832   y = y + Editor_state.line_height
1833   App.screen.check(y, 'jkl mno pqr ', 'baseline2/screen:2')
1834   y = y + Editor_state.line_height
1835   App.screen.check(y, 'stu', 'baseline2/screen:3')
1836   -- try to move the cursor earlier in the third screen line by clicking the mouse
1837   edit.run_after_mouse_release(Editor_state, Editor_state.left+2,Editor_state.top+Editor_state.line_height*2+5, 1)
1838   -- cursor should move
1839   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
1840   check_eq(Editor_state.cursor1.pos, 25, 'cursor:pos')
1841 end
1842
1843 function test_backspace_can_scroll_up()
1844   -- display the lines 2/3/4 with the cursor on line 2
1845   App.screen.init{width=120, height=60}
1846   Editor_state = edit.initialize_test_state()
1847   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl'}
1848   Text.redraw_all(Editor_state)
1849   Editor_state.cursor1 = {line=2, pos=1}
1850   Editor_state.screen_top1 = {line=2, pos=1}
1851   Editor_state.screen_bottom1 = {}
1852   edit.draw(Editor_state)
1853   local y = Editor_state.top
1854   App.screen.check(y, 'def', 'baseline/screen:1')
1855   y = y + Editor_state.line_height
1856   App.screen.check(y, 'ghi', 'baseline/screen:2')
1857   y = y + Editor_state.line_height
1858   App.screen.check(y, 'jkl', 'baseline/screen:3')
1859   -- after hitting backspace the screen scrolls up by one line
1860   edit.run_after_keychord(Editor_state, 'backspace')
1861   check_eq(Editor_state.screen_top1.line, 1, 'screen_top')
1862   check_eq(Editor_state.cursor1.line, 1, 'cursor')
1863   y = Editor_state.top
1864   App.screen.check(y, 'abcdef', 'screen:1')
1865   y = y + Editor_state.line_height
1866   App.screen.check(y, 'ghi', 'screen:2')
1867   y = y + Editor_state.line_height
1868   App.screen.check(y, 'jkl', 'screen:3')
1869 end
1870
1871 function test_backspace_can_scroll_up_screen_line()
1872   -- display lines starting from second screen line of a line
1873   App.screen.init{width=Editor_state.left+30, height=60}
1874   Editor_state = edit.initialize_test_state()
1875   Editor_state.lines = load_array{'abc', 'def', 'ghi jkl', 'mno'}
1876   Text.redraw_all(Editor_state)
1877   Editor_state.cursor1 = {line=3, pos=5}
1878   Editor_state.screen_top1 = {line=3, pos=5}
1879   Editor_state.screen_bottom1 = {}
1880   edit.draw(Editor_state)
1881   local y = Editor_state.top
1882   App.screen.check(y, 'jkl', 'baseline/screen:1')
1883   y = y + Editor_state.line_height
1884   App.screen.check(y, 'mno', 'baseline/screen:2')
1885   -- after hitting backspace the screen scrolls up by one screen line
1886   edit.run_after_keychord(Editor_state, 'backspace')
1887   y = Editor_state.top
1888   App.screen.check(y, 'ghij', 'screen:1')
1889   y = y + Editor_state.line_height
1890   App.screen.check(y, 'kl', 'screen:2')
1891   y = y + Editor_state.line_height
1892   App.screen.check(y, 'mno', 'screen:3')
1893   check_eq(Editor_state.screen_top1.line, 3, 'screen_top:line')
1894   check_eq(Editor_state.screen_top1.pos, 1, 'screen_top:pos')
1895   check_eq(Editor_state.cursor1.line, 3, 'cursor:line')
1896   check_eq(Editor_state.cursor1.pos, 4, 'cursor:pos')
1897 end
1898
1899 function test_backspace_past_line_boundary()
1900   -- position cursor at start of a (non-first) line
1901   App.screen.init{width=Editor_state.left+30, height=60}
1902   Editor_state = edit.initialize_test_state()
1903   Editor_state.lines = load_array{'abc', 'def'}
1904   Text.redraw_all(Editor_state)
1905   Editor_state.cursor1 = {line=2, pos=1}
1906   -- backspace joins with previous line
1907   edit.run_after_keychord(Editor_state, 'backspace')
1908   check_eq(Editor_state.lines[1].data, 'abcdef', 'check')
1909 end
1910
1911 -- some tests for operating over selections created using Shift- chords
1912 -- we're just testing delete_selection, and it works the same for all keys
1913
1914 function test_backspace_over_selection()
1915   -- select just one character within a line with cursor before selection
1916   App.screen.init{width=Editor_state.left+30, height=60}
1917   Editor_state = edit.initialize_test_state()
1918   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl', 'mno'}
1919   Text.redraw_all(Editor_state)
1920   Editor_state.cursor1 = {line=1, pos=1}
1921   Editor_state.selection1 = {line=1, pos=2}
1922   -- backspace deletes the selected character, even though it's after the cursor
1923   edit.run_after_keychord(Editor_state, 'backspace')
1924   check_eq(Editor_state.lines[1].data, 'bc', 'data')
1925   -- cursor (remains) at start of selection
1926   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
1927   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
1928   -- selection is cleared
1929   check_nil(Editor_state.selection1.line, 'selection')
1930 end
1931
1932 function test_backspace_over_selection_reverse()
1933   -- select just one character within a line with cursor after selection
1934   App.screen.init{width=Editor_state.left+30, height=60}
1935   Editor_state = edit.initialize_test_state()
1936   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl', 'mno'}
1937   Text.redraw_all(Editor_state)
1938   Editor_state.cursor1 = {line=1, pos=2}
1939   Editor_state.selection1 = {line=1, pos=1}
1940   -- backspace deletes the selected character
1941   edit.run_after_keychord(Editor_state, 'backspace')
1942   check_eq(Editor_state.lines[1].data, 'bc', 'data')
1943   -- cursor moves to start of selection
1944   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
1945   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
1946   -- selection is cleared
1947   check_nil(Editor_state.selection1.line, 'selection')
1948 end
1949
1950 function test_backspace_over_multiple_lines()
1951   -- select just one character within a line with cursor after selection
1952   App.screen.init{width=Editor_state.left+30, height=60}
1953   Editor_state = edit.initialize_test_state()
1954   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl', 'mno'}
1955   Text.redraw_all(Editor_state)
1956   Editor_state.cursor1 = {line=1, pos=2}
1957   Editor_state.selection1 = {line=4, pos=2}
1958   -- backspace deletes the region and joins the remaining portions of lines on either side
1959   edit.run_after_keychord(Editor_state, 'backspace')
1960   check_eq(Editor_state.lines[1].data, 'akl', 'data:1')
1961   check_eq(Editor_state.lines[2].data, 'mno', 'data:2')
1962   -- cursor remains at start of selection
1963   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
1964   check_eq(Editor_state.cursor1.pos, 2, 'cursor:pos')
1965   -- selection is cleared
1966   check_nil(Editor_state.selection1.line, 'selection')
1967 end
1968
1969 function test_backspace_to_end_of_line()
1970   -- select region from cursor to end of line
1971   App.screen.init{width=Editor_state.left+30, height=60}
1972   Editor_state = edit.initialize_test_state()
1973   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl', 'mno'}
1974   Text.redraw_all(Editor_state)
1975   Editor_state.cursor1 = {line=1, pos=2}
1976   Editor_state.selection1 = {line=1, pos=4}
1977   -- backspace deletes rest of line without joining to any other line
1978   edit.run_after_keychord(Editor_state, 'backspace')
1979   check_eq(Editor_state.lines[1].data, 'a', 'data:1')
1980   check_eq(Editor_state.lines[2].data, 'def', 'data:2')
1981   -- cursor remains at start of selection
1982   check_eq(Editor_state.cursor1.line, 1, 'cursor:line')
1983   check_eq(Editor_state.cursor1.pos, 2, 'cursor:pos')
1984   -- selection is cleared
1985   check_nil(Editor_state.selection1.line, 'selection')
1986 end
1987
1988 function test_backspace_to_start_of_line()
1989   -- select region from cursor to start of line
1990   App.screen.init{width=Editor_state.left+30, height=60}
1991   Editor_state = edit.initialize_test_state()
1992   Editor_state.lines = load_array{'abc', 'def', 'ghi', 'jkl', 'mno'}
1993   Text.redraw_all(Editor_state)
1994   Editor_state.cursor1 = {line=2, pos=1}
1995   Editor_state.selection1 = {line=2, pos=3}
1996   -- backspace deletes beginning of line without joining to any other line
1997   edit.run_after_keychord(Editor_state, 'backspace')
1998   check_eq(Editor_state.lines[1].data, 'abc', 'data:1')
1999   check_eq(Editor_state.lines[2].data, 'f', 'data:2')
2000   -- cursor remains at start of selection
2001   check_eq(Editor_state.cursor1.line, 2, 'cursor:line')
2002   check_eq(Editor_state.cursor1.pos, 1, 'cursor:pos')
2003   -- selection is cleared
2004   check_nil(Editor_state.selection1.line, 'selection')
2005 end
2006
2007 function test_undo_insert_text()
2008   App.screen.init{width=120, height=60}
2009   Editor_state = edit.initialize_test_state()
2010   Editor_state.lines = load_array{'abc', 'def', 'xyz'}
2011   Text.redraw_all(Editor_state)
2012   Editor_state.cursor1 = {line=2, pos=4}
2013   Editor_state.screen_top1 = {line=1, pos=1}
2014   Editor_state.screen_bottom1 = {}
2015   -- insert a character
2016   edit.draw(Editor_state)
2017   edit.run_after_text_input(Editor_state, 'g')
2018   check_eq(Editor_state.cursor1.line, 2, 'baseline/cursor:line')
2019   check_eq(Editor_state.cursor1.pos, 5, 'baseline/cursor:pos')
2020   check_nil(Editor_state.selection1.line, 'baseline/selection:line')
2021   check_nil(Editor_state.selection1.pos, 'baseline/selection:pos')
2022   local y = Editor_state.top
2023   App.screen.check(y, 'abc', 'baseline/screen:1')
2024   y = y + Editor_state.line_height
2025   App.screen.check(y, 'defg', 'baseline/screen:2')
2026   y = y + Editor_state.line_height
2027   App.screen.check(y, 'xyz', 'baseline/screen:3')
2028   -- undo
2029   edit.run_after_keychord(Editor_state, 'C-z')
2030   check_eq(Editor_state.cursor1.line, 2, 'cursor:line')
2031   check_eq(Editor_state.cursor1.pos, 4, 'cursor:pos')
2032   check_nil(Editor_state.selection1.line, 'selection:line')
2033   check_nil(Editor_state.selection1.pos, 'selection:pos')
2034   y = Editor_state.top
2035   App.screen.check(y, 'abc', 'screen:1')
2036   y = y + Editor_state.line_height
2037   App.screen.check(y, 'def', 'screen:2')
2038   y = y + Editor_state.line_height
2039   App.screen.check(y, 'xyz', 'screen:3')
2040 end
2041
2042 function test_undo_delete_text()
2043   App.screen.init{width=120, height=60}
2044   Editor_state = edit.initialize_test_state()
2045   Editor_state.lines = load_array{'abc', 'defg', 'xyz'}
2046   Text.redraw_all(Editor_state)
2047   Editor_state.cursor1 = {line=2, pos=5}
2048   Editor_state.screen_top1 = {line=1, pos=1}
2049   Editor_state.screen_bottom1 = {}
2050   -- delete a character
2051   edit.run_after_keychord(Editor_state, 'backspace')
2052   check_eq(Editor_state.cursor1.line, 2, 'baseline/cursor:line')
2053   check_eq(Editor_state.cursor1.pos, 4, 'baseline/cursor:pos')
2054   check_nil(Editor_state.selection1.line, 'baseline/selection:line')
2055   check_nil(Editor_state.selection1.pos, 'baseline/selection:pos')
2056   local y = Editor_state.top
2057   App.screen.check(y, 'abc', 'baseline/screen:1')
2058   y = y + Editor_state.line_height
2059   App.screen.check(y, 'def', 'baseline/screen:2')
2060   y = y + Editor_state.line_height
2061   App.screen.check(y, 'xyz', 'baseline/screen:3')
2062   -- undo
2063 --?   -- after undo, the backspaced key is selected
2064   edit.run_after_keychord(Editor_state, 'C-z')
2065   check_eq(Editor_state.cursor1.line, 2, 'cursor:line')
2066   check_eq(Editor_state.cursor1.pos, 5, 'cursor:pos')
2067   check_nil(Editor_state.selection1.line, 'selection:line')
2068   check_nil(Editor_state.selection1.pos, 'selection:pos')
2069 --?   check_eq(Editor_state.selection1.line, 2, 'selection:line')
2070 --?   check_eq(Editor_state.selection1.pos, 4, 'selection:pos')
2071   y = Editor_state.top
2072   App.screen.check(y, 'abc', 'screen:1')
2073   y = y + Editor_state.line_height
2074   App.screen.check(y, 'defg', 'screen:2')
2075   y = y + Editor_state.line_height
2076   App.screen.check(y, 'xyz', 'screen:3')
2077 end
2078
2079 function test_undo_restores_selection()
2080   -- display a line of text with some part selected
2081   App.screen.init{width=75, height=80}
2082   Editor_state = edit.initialize_test_state()
2083   Editor_state.lines = load_array{'abc'}
2084   Text.redraw_all(Editor_state)
2085   Editor_state.cursor1 = {line=1, pos=1}
2086   Editor_state.selection1 = {line=1, pos=2}
2087   Editor_state.screen_top1 = {line=1, pos=1}
2088   Editor_state.screen_bottom1 = {}
2089   edit.draw(Editor_state)
2090   -- delete selected text
2091   edit.run_after_text_input(Editor_state, 'x')
2092   check_eq(Editor_state.lines[1].data, 'xbc', 'baseline')
2093   check_nil(Editor_state.selection1.line, 'baseline:selection')
2094   -- undo
2095   edit.run_after_keychord(Editor_state, 'C-z')
2096   edit.run_after_keychord(Editor_state, 'C-z')
2097   -- selection is restored
2098   check_eq(Editor_state.selection1.line, 1, 'line')
2099   check_eq(Editor_state.selection1.pos, 2, 'pos')
2100 end
2101
2102 function test_search()
2103   App.screen.init{width=120, height=60}
2104   Editor_state = edit.initialize_test_state()
2105   Editor_state.lines = load_array{'```lines', '```', 'def', 'ghi', '’deg'}  -- contains unicode quote in final line
2106   Text.redraw_all(Editor_state)
2107   Editor_state.cursor1 = {line=1, pos=1}
2108   Editor_state.screen_top1 = {line=1, pos=1}
2109   Editor_state.screen_bottom1 = {}
2110   edit.draw(Editor_state)
2111   -- search for a string
2112   edit.run_after_keychord(Editor_state, 'C-f')
2113   edit.run_after_text_input(Editor_state, 'd')
2114   edit.run_after_keychord(Editor_state, 'return')
2115   check_eq(Editor_state.cursor1.line, 2, '1/cursor:line')
2116   check_eq(Editor_state.cursor1.pos, 1, '1/cursor:pos')
2117   -- reset cursor
2118   Editor_state.cursor1 = {line=1, pos=1}
2119   Editor_state.screen_top1 = {line=1, pos=1}
2120   -- search for second occurrence
2121   edit.run_after_keychord(Editor_state, 'C-f')
2122   edit.run_after_text_input(Editor_state, 'de')
2123   edit.run_after_keychord(Editor_state, 'down')
2124   edit.run_after_keychord(Editor_state, 'return')
2125   check_eq(Editor_state.cursor1.line, 4, '2/cursor:line')
2126   check_eq(Editor_state.cursor1.pos, 2, '2/cursor:pos')
2127 end
2128
2129 function test_search_upwards()
2130   App.screen.init{width=120, height=60}
2131   Editor_state = edit.initialize_test_state()
2132   Editor_state.lines = load_array{'’abc', 'abd'}  -- contains unicode quote
2133   Text.redraw_all(Editor_state)
2134   Editor_state.cursor1 = {line=2, pos=1}
2135   Editor_state.screen_top1 = {line=1, pos=1}
2136   Editor_state.screen_bottom1 = {}
2137   edit.draw(Editor_state)
2138   -- search for a string
2139   edit.run_after_keychord(Editor_state, 'C-f')
2140   edit.run_after_text_input(Editor_state, 'a')
2141   -- search for previous occurrence
2142   edit.run_after_keychord(Editor_state, 'up')
2143   check_eq(Editor_state.cursor1.line, 1, '2/cursor:line')
2144   check_eq(Editor_state.cursor1.pos, 2, '2/cursor:pos')
2145 end
2146
2147 function test_search_wrap()
2148   App.screen.init{width=120, height=60}
2149   Editor_state = edit.initialize_test_state()
2150   Editor_state.lines = load_array{'’abc', 'def'}  -- contains unicode quote in first line
2151   Text.redraw_all(Editor_state)
2152   Editor_state.cursor1 = {line=2, pos=1}
2153   Editor_state.screen_top1 = {line=1, pos=1}
2154   Editor_state.screen_bottom1 = {}
2155   edit.draw(Editor_state)
2156   -- search for a string
2157   edit.run_after_keychord(Editor_state, 'C-f')
2158   edit.run_after_text_input(Editor_state, 'a')
2159   edit.run_after_keychord(Editor_state, 'return')
2160   -- cursor wraps
2161   check_eq(Editor_state.cursor1.line, 1, '1/cursor:line')
2162   check_eq(Editor_state.cursor1.pos, 2, '1/cursor:pos')
2163 end
2164
2165 function test_search_wrap_upwards()
2166   App.screen.init{width=120, height=60}
2167   Editor_state = edit.initialize_test_state()
2168   Editor_state.lines = load_array{'abc ’abd'}  -- contains unicode quote
2169   Text.redraw_all(Editor_state)
2170   Editor_state.cursor1 = {line=1, pos=1}
2171   Editor_state.screen_top1 = {line=1, pos=1}
2172   Editor_state.screen_bottom1 = {}
2173   edit.draw(Editor_state)
2174   -- search upwards for a string
2175   edit.run_after_keychord(Editor_state, 'C-f')
2176   edit.run_after_text_input(Editor_state, 'a')
2177   edit.run_after_keychord(Editor_state, 'up')
2178   -- cursor wraps
2179   check_eq(Editor_state.cursor1.line, 1, '1/cursor:line')
2180   check_eq(Editor_state.cursor1.pos, 6, '1/cursor:pos')
2181 end