source_text_tests.lua

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