| 🛟 Updated. 28d5985 k33g 21h ago | 1 | package terminal |
| 2 | |
| 3 | import ( |
| 4 | "strings" |
| 5 | "testing" |
| 6 | |
| 7 | "github.com/gdamore/tcell/v2" |
| 8 | ) |
| 9 | |
| 10 | // writeString puts a run of characters onto a screen, as a program would. |
| 11 | func writeString(s *Screen, text string) { |
| 12 | for _, r := range text { |
| 13 | s.WriteRune(r) |
| 14 | } |
| 15 | } |
| 16 | |
| 17 | // wantLines fails the test unless the screen's rows read as expected. Rows |
| 18 | // beyond the ones given are not checked. |
| 19 | func wantLines(t *testing.T, s *Screen, lines ...string) { |
| 20 | t.Helper() |
| 21 | for row, want := range lines { |
| 22 | if got := s.LineText(row); got != want { |
| 23 | t.Errorf("row %d = %q, want %q", row, got, want) |
| 24 | } |
| 25 | } |
| 26 | } |
| 27 | |
| 28 | func TestANewScreenIsBlankWithTheCursorAtTheTopLeft(t *testing.T) { |
| 29 | s := NewScreen(20, 5) |
| 30 | |
| 31 | width, height := s.Size() |
| 32 | if width != 20 || height != 5 { |
| 33 | t.Errorf("Size() = %dx%d, want 20x5", width, height) |
| 34 | } |
| 35 | if got := s.Cursor(); got != (Cursor{}) { |
| 36 | t.Errorf("Cursor() = %+v, want the top left", got) |
| 37 | } |
| 38 | if !s.CursorVisible() { |
| 39 | t.Error("CursorVisible() = false on a new screen") |
| 40 | } |
| 41 | for row := range 5 { |
| 42 | if got := s.LineText(row); got != "" { |
| 43 | t.Errorf("row %d = %q, want it blank", row, got) |
| 44 | } |
| 45 | } |
| 46 | } |
| 47 | |
| 48 | func TestASizeBelowOneIsRaisedToOne(t *testing.T) { |
| 49 | s := NewScreen(0, -3) |
| 50 | |
| 51 | if width, height := s.Size(); width != 1 || height != 1 { |
| 52 | t.Errorf("Size() = %dx%d, want 1x1 — the cursor must have somewhere to be", width, height) |
| 53 | } |
| 54 | s.WriteRune('x') // must not panic |
| 55 | } |
| 56 | |
| 57 | func TestWritingAdvancesTheCursor(t *testing.T) { |
| 58 | s := NewScreen(20, 3) |
| 59 | |
| 60 | writeString(s, "hello") |
| 61 | |
| 62 | wantLines(t, s, "hello") |
| 63 | if got := s.Cursor(); got != (Cursor{Row: 0, Col: 5}) { |
| 64 | t.Errorf("Cursor() = %+v, want column 5", got) |
| 65 | } |
| 66 | } |
| 67 | |
| 68 | func TestTheCursorStopsInTheLastColumnUntilTheNextCharacter(t *testing.T) { |
| 69 | // A character written in the last column must not scroll the screen by |
| 70 | // itself. Only the character after it wraps. |
| 71 | s := NewScreen(3, 2) |
| 72 | |
| 73 | writeString(s, "abc") |
| 74 | |
| 75 | if got := s.Cursor(); got != (Cursor{Row: 0, Col: 2}) { |
| 76 | t.Fatalf("Cursor() = %+v, want it parked in the last column", got) |
| 77 | } |
| 78 | wantLines(t, s, "abc", "") |
| 79 | |
| 80 | s.WriteRune('d') |
| 81 | wantLines(t, s, "abc", "d") |
| 82 | } |
| 83 | |
| 84 | func TestWrappingCanBeTurnedOff(t *testing.T) { |
| 85 | s := NewScreen(3, 2) |
| 86 | s.SetAutoWrap(false) |
| 87 | |
| 88 | writeString(s, "abcdef") |
| 89 | |
| 90 | wantLines(t, s, "abf", "") |
| 91 | if got := s.Cursor(); got != (Cursor{Row: 0, Col: 2}) { |
| 92 | t.Errorf("Cursor() = %+v, want it held in the last column", got) |
| 93 | } |
| 94 | } |
| 95 | |
| 96 | func TestMoveToClampsToTheScreen(t *testing.T) { |
| 97 | s := NewScreen(10, 4) |
| 98 | |
| 99 | tests := []struct { |
| 100 | name string |
| 101 | row, col int |
| 102 | want Cursor |
| 103 | }{ |
| 104 | {"inside", 2, 3, Cursor{Row: 2, Col: 3}}, |
| 105 | {"past the bottom", 99, 0, Cursor{Row: 3, Col: 0}}, |
| 106 | {"past the right", 0, 99, Cursor{Row: 0, Col: 9}}, |
| 107 | {"negative", -5, -5, Cursor{}}, |
| 108 | } |
| 109 | |
| 110 | for _, tc := range tests { |
| 111 | t.Run(tc.name, func(t *testing.T) { |
| 112 | s.MoveTo(tc.row, tc.col) |
| 113 | if got := s.Cursor(); got != tc.want { |
| 114 | t.Errorf("MoveTo(%d, %d) gave %+v, want %+v", tc.row, tc.col, got, tc.want) |
| 115 | } |
| 116 | }) |
| 117 | } |
| 118 | } |
| 119 | |
| 120 | func TestCarriageReturnAndLineFeed(t *testing.T) { |
| 121 | s := NewScreen(10, 3) |
| 122 | writeString(s, "one") |
| 123 | |
| 124 | s.CarriageReturn() |
| 125 | if got := s.Cursor().Col; got != 0 { |
| 126 | t.Errorf("after a carriage return the cursor is at column %d, want 0", got) |
| 127 | } |
| 128 | |
| 129 | s.LineFeed() |
| 130 | if got := s.Cursor(); got != (Cursor{Row: 1, Col: 0}) { |
| 131 | t.Errorf("Cursor() = %+v, want the start of the next line", got) |
| 132 | } |
| 133 | } |
| 134 | |
| 135 | func TestALineFeedOnTheLastRowScrolls(t *testing.T) { |
| 136 | s := NewScreen(10, 3) |
| 137 | for _, text := range []string{"one", "two", "three"} { |
| 138 | writeString(s, text) |
| 139 | s.CarriageReturn() |
| 140 | s.LineFeed() |
| 141 | } |
| 142 | |
| 143 | wantLines(t, s, "two", "three", "") |
| 144 | if got := s.ScrollbackLen(); got != 1 { |
| 145 | t.Errorf("ScrollbackLen() = %d, want the scrolled-off line kept", got) |
| 146 | } |
| 147 | } |
| 148 | |
| 149 | func TestReverseLineFeedScrollsDownAtTheTop(t *testing.T) { |
| 150 | s := NewScreen(10, 3) |
| 151 | writeString(s, "one") |
| 152 | s.MoveTo(0, 0) |
| 153 | |
| 154 | s.ReverseLineFeed() |
| 155 | |
| 156 | wantLines(t, s, "", "one") |
| 157 | if got := s.Cursor().Row; got != 0 { |
| 158 | t.Errorf("Cursor().Row = %d, want it held at the top", got) |
| 159 | } |
| 160 | } |
| 161 | |
| 162 | func TestBackspaceMovesWithoutErasing(t *testing.T) { |
| 163 | s := NewScreen(10, 2) |
| 164 | writeString(s, "abc") |
| 165 | |
| 166 | s.Backspace() |
| 167 | |
| 168 | if got := s.Cursor().Col; got != 2 { |
| 169 | t.Errorf("Cursor().Col = %d, want 2", got) |
| 170 | } |
| 171 | wantLines(t, s, "abc") |
| 172 | |
| 173 | s.MoveTo(0, 0) |
| 174 | s.Backspace() |
| 175 | if got := s.Cursor().Col; got != 0 { |
| 176 | t.Errorf("Cursor().Col = %d, want it held at the first column", got) |
| 177 | } |
| 178 | } |
| 179 | |
| 180 | func TestTabMovesToTheNextStop(t *testing.T) { |
| 181 | s := NewScreen(30, 2) |
| 182 | |
| 183 | s.Tab() |
| 184 | if got := s.Cursor().Col; got != TabWidth { |
| 185 | t.Errorf("Cursor().Col = %d, want %d", got, TabWidth) |
| 186 | } |
| 187 | |
| 188 | s.MoveTo(0, 3) |
| 189 | s.Tab() |
| 190 | if got := s.Cursor().Col; got != TabWidth { |
| 191 | t.Errorf("Cursor().Col = %d, want the next stop at %d", got, TabWidth) |
| 192 | } |
| 193 | } |
| 194 | |
| 195 | func TestTabStopsAtTheLastColumn(t *testing.T) { |
| 196 | s := NewScreen(10, 2) |
| 197 | s.MoveTo(0, 9) |
| 198 | |
| 199 | s.Tab() |
| 200 | |
| 201 | if got := s.Cursor().Col; got != 9 { |
| 202 | t.Errorf("Cursor().Col = %d, want it held in the last column", got) |
| 203 | } |
| 204 | } |
| 205 | |
| 206 | func TestSaveAndRestoreCursorCarryTheStyle(t *testing.T) { |
| 207 | s := NewScreen(10, 4) |
| 208 | s.MoveTo(2, 3) |
| 209 | s.SetStyle(tcell.StyleDefault.Bold(true)) |
| 210 | |
| 211 | s.SaveCursor() |
| 212 | s.MoveTo(0, 0) |
| 213 | s.SetStyle(tcell.StyleDefault) |
| 214 | s.RestoreCursor() |
| 215 | |
| 216 | if got := s.Cursor(); got != (Cursor{Row: 2, Col: 3}) { |
| 217 | t.Errorf("Cursor() = %+v, want what was saved", got) |
| 218 | } |
| 219 | if _, _, attrs := s.Style().Decompose(); attrs&tcell.AttrBold == 0 { |
| 220 | t.Error("the saved style was not restored") |
| 221 | } |
| 222 | } |
| 223 | |
| 224 | func TestEraseDisplay(t *testing.T) { |
| 225 | fill := func() *Screen { |
| 226 | s := NewScreen(5, 3) |
| 227 | for row, text := range []string{"aaaaa", "bbbbb", "ccccc"} { |
| 228 | s.MoveTo(row, 0) |
| 229 | writeString(s, text) |
| 230 | } |
| 231 | s.MoveTo(1, 2) |
| 232 | return s |
| 233 | } |
| 234 | |
| 235 | tests := []struct { |
| 236 | name string |
| 237 | mode EraseMode |
| 238 | lines []string |
| 239 | }{ |
| 240 | {"to the end", EraseToEnd, []string{"aaaaa", "bb", ""}}, |
| 241 | {"to the start", EraseToStart, []string{"", " bb", "ccccc"}}, |
| 242 | {"all of it", EraseAll, []string{"", "", ""}}, |
| 243 | } |
| 244 | |
| 245 | for _, tc := range tests { |
| 246 | t.Run(tc.name, func(t *testing.T) { |
| 247 | s := fill() |
| 248 | s.EraseDisplay(tc.mode) |
| 249 | wantLines(t, s, tc.lines...) |
| 250 | if got := s.Cursor(); got != (Cursor{Row: 1, Col: 2}) { |
| 251 | t.Errorf("Cursor() = %+v, want it left where it was", got) |
| 252 | } |
| 253 | }) |
| 254 | } |
| 255 | } |
| 256 | |
| 257 | func TestEraseLine(t *testing.T) { |
| 258 | tests := []struct { |
| 259 | name string |
| 260 | mode EraseMode |
| 261 | want string |
| 262 | }{ |
| 263 | {"to the end", EraseToEnd, "ab"}, |
| 264 | {"to the start", EraseToStart, " de"}, |
| 265 | {"all of it", EraseAll, ""}, |
| 266 | } |
| 267 | |
| 268 | for _, tc := range tests { |
| 269 | t.Run(tc.name, func(t *testing.T) { |
| 270 | s := NewScreen(5, 2) |
| 271 | writeString(s, "abcde") |
| 272 | s.MoveTo(0, 2) |
| 273 | |
| 274 | s.EraseLine(tc.mode) |
| 275 | |
| 276 | wantLines(t, s, tc.want) |
| 277 | }) |
| 278 | } |
| 279 | } |
| 280 | |
| 281 | func TestEraseCharsBlanksInPlace(t *testing.T) { |
| 282 | s := NewScreen(6, 2) |
| 283 | writeString(s, "abcdef") |
| 284 | s.MoveTo(0, 1) |
| 285 | |
| 286 | s.EraseChars(3) |
| 287 | |
| 288 | wantLines(t, s, "a ef") |
| 289 | } |
| 290 | |
| 291 | func TestInsertAndDeleteChars(t *testing.T) { |
| 292 | s := NewScreen(6, 2) |
| 293 | writeString(s, "abcdef") |
| 294 | s.MoveTo(0, 2) |
| 295 | |
| 296 | s.DeleteChars(2) |
| 297 | wantLines(t, s, "abef") |
| 298 | |
| 299 | s.MoveTo(0, 2) |
| 300 | s.InsertChars(2) |
| 301 | wantLines(t, s, "ab ef") |
| 302 | } |
| 303 | |
| 304 | func TestInsertAndDeleteCharsAreClampedToTheLine(t *testing.T) { |
| 305 | s := NewScreen(4, 2) |
| 306 | writeString(s, "abcd") |
| 307 | s.MoveTo(0, 2) |
| 308 | |
| 309 | s.DeleteChars(99) // must not read past the line |
| 310 | wantLines(t, s, "ab") |
| 311 | |
| 312 | s.InsertChars(99) |
| 313 | wantLines(t, s, "ab") |
| 314 | } |
| 315 | |
| 316 | func TestInsertAndDeleteLines(t *testing.T) { |
| 317 | build := func() *Screen { |
| 318 | s := NewScreen(5, 4) |
| 319 | for row, text := range []string{"one", "two", "three", "four"} { |
| 320 | s.MoveTo(row, 0) |
| 321 | writeString(s, text) |
| 322 | } |
| 323 | s.MoveTo(1, 0) |
| 324 | return s |
| 325 | } |
| 326 | |
| 327 | s := build() |
| 328 | s.InsertLines(1) |
| 329 | wantLines(t, s, "one", "", "two", "three") |
| 330 | |
| 331 | s = build() |
| 332 | s.DeleteLines(1) |
| 333 | wantLines(t, s, "one", "three", "four", "") |
| 334 | } |
| 335 | |
| 336 | func TestInsertLinesOutsideTheScrollRegionDoesNothing(t *testing.T) { |
| 337 | // A program with a status line on row 0 narrows the region so that its |
| 338 | // status line stays put; an insert from outside must not push it about. |
| 339 | s := NewScreen(5, 4) |
| 340 | s.MoveTo(0, 0) |
| 341 | writeString(s, "stay") |
| 342 | s.SetScrollRegion(1, 3) |
| 343 | s.MoveTo(0, 0) |
| 344 | |
| 345 | s.InsertLines(2) |
| 346 | |
| 347 | wantLines(t, s, "stay") |
| 348 | } |
| 349 | |
| 350 | func TestTheScrollRegionLimitsScrolling(t *testing.T) { |
| 351 | s := NewScreen(5, 4) |
| 352 | for row, text := range []string{"head", "a", "b", "c"} { |
| 353 | s.MoveTo(row, 0) |
| 354 | writeString(s, text) |
| 355 | } |
| 356 | |
| 357 | s.SetScrollRegion(1, 3) |
| 358 | s.MoveTo(3, 0) |
| 359 | s.LineFeed() |
| 360 | |
| 361 | wantLines(t, s, "head", "b", "c", "") |
| 362 | } |
| 363 | |
| 364 | func TestSettingTheScrollRegionMovesTheCursorHome(t *testing.T) { |
| 365 | s := NewScreen(5, 4) |
| 366 | s.MoveTo(3, 3) |
| 367 | |
| 368 | s.SetScrollRegion(1, 3) |
| 369 | |
| 370 | if got := s.Cursor(); got != (Cursor{}) { |
| 371 | t.Errorf("Cursor() = %+v, want the top left", got) |
| 372 | } |
| 373 | } |
| 374 | |
| 375 | func TestAnImpossibleScrollRegionIsIgnored(t *testing.T) { |
| 376 | s := NewScreen(5, 4) |
| 377 | s.SetScrollRegion(1, 3) |
| 378 | s.MoveTo(2, 2) |
| 379 | |
| 380 | s.SetScrollRegion(3, 1) // the wrong way round |
| 381 | s.SetScrollRegion(2, 2) // empty |
| 382 | |
| 383 | s.MoveTo(3, 0) |
| 384 | s.LineFeed() |
| 385 | if got := s.Cursor().Row; got != 3 { |
| 386 | t.Errorf("Cursor().Row = %d, want the earlier region still in force", got) |
| 387 | } |
| 388 | } |
| 389 | |
| 390 | func TestScrollingANarrowRegionIsNotHistory(t *testing.T) { |
| 391 | // Lines leaving a narrow region are part of a program redrawing its own |
| 392 | // display, not lines the session has finished with. |
| 393 | s := NewScreen(5, 4) |
| 394 | s.SetScrollRegion(1, 3) |
| 395 | s.MoveTo(3, 0) |
| 396 | |
| 397 | s.LineFeed() |
| 398 | |
| 399 | if got := s.ScrollbackLen(); got != 0 { |
| 400 | t.Errorf("ScrollbackLen() = %d, want nothing remembered", got) |
| 401 | } |
| 402 | } |
| 403 | |
| 404 | func TestScrollbackKeepsWhatLeavesTheTop(t *testing.T) { |
| 405 | s := NewScreen(10, 2) |
| 406 | for _, text := range []string{"one", "two", "three", "four"} { |
| 407 | writeString(s, text) |
| 408 | s.CarriageReturn() |
| 409 | s.LineFeed() |
| 410 | } |
| 411 | |
| 412 | if got := s.ScrollbackLen(); got != 3 { |
| 413 | t.Fatalf("ScrollbackLen() = %d, want 3", got) |
| 414 | } |
| 415 | if got := lineText(s.ScrollbackLine(0)); got != "one" { |
| 416 | t.Errorf("the oldest scrollback line is %q, want %q", got, "one") |
| 417 | } |
| 418 | if s.ScrollbackLine(-1) != nil || s.ScrollbackLine(99) != nil { |
| 419 | t.Error("ScrollbackLine outside the history returned something") |
| 420 | } |
| 421 | } |
| 422 | |
| 423 | func TestScrollbackIsCapped(t *testing.T) { |
| 424 | s := NewScreen(10, 2) |
| 425 | s.SetMaxScrollback(3) |
| 426 | |
| 427 | for i := range 20 { |
| 428 | writeString(s, string(rune('a'+i%26))) |
| 429 | s.CarriageReturn() |
| 430 | s.LineFeed() |
| 431 | } |
| 432 | |
| 433 | if got := s.ScrollbackLen(); got != 3 { |
| 434 | t.Errorf("ScrollbackLen() = %d, want the cap of 3", got) |
| 435 | } |
| 436 | } |
| 437 | |
| 438 | func TestScrollbackCanBeTurnedOff(t *testing.T) { |
| 439 | s := NewScreen(10, 2) |
| 440 | s.SetMaxScrollback(0) |
| 441 | |
| 442 | for range 5 { |
| 443 | s.LineFeed() |
| 444 | } |
| 445 | |
| 446 | if got := s.ScrollbackLen(); got != 0 { |
| 447 | t.Errorf("ScrollbackLen() = %d, want none kept", got) |
| 448 | } |
| 449 | } |
| 450 | |
| 451 | func TestTheAlternateScreenIsAScratchSurface(t *testing.T) { |
| 452 | s := NewScreen(10, 3) |
| 453 | writeString(s, "before") |
| 454 | |
| 455 | s.UseAlternate(true) |
| 456 | |
| 457 | if !s.Alternate() { |
| 458 | t.Fatal("Alternate() = false after switching to it") |
| 459 | } |
| 460 | wantLines(t, s, "") |
| 461 | if got := s.Cursor(); got != (Cursor{}) { |
| 462 | t.Errorf("Cursor() = %+v, want the top left of a fresh screen", got) |
| 463 | } |
| 464 | |
| 465 | writeString(s, "during") |
| 466 | s.UseAlternate(false) |
| 467 | |
| 468 | if s.Alternate() { |
| 469 | t.Fatal("Alternate() = true after switching back") |
| 470 | } |
| 471 | wantLines(t, s, "before") |
| 472 | } |
| 473 | |
| 474 | func TestSwitchingToTheScreenAlreadyShowingDoesNothing(t *testing.T) { |
| 475 | s := NewScreen(10, 3) |
| 476 | writeString(s, "kept") |
| 477 | |
| 478 | s.UseAlternate(false) // already on the primary |
| 479 | |
| 480 | wantLines(t, s, "kept") |
| 481 | } |
| 482 | |
| 483 | func TestTheAlternateScreenHasNoScrollback(t *testing.T) { |
| 484 | s := NewScreen(10, 2) |
| 485 | s.UseAlternate(true) |
| 486 | |
| 487 | for range 5 { |
| 488 | s.LineFeed() |
| 489 | } |
| 490 | |
| 491 | if got := s.ScrollbackLen(); got != 0 { |
| 492 | t.Errorf("ScrollbackLen() = %d, want none on a scratch surface", got) |
| 493 | } |
| 494 | } |
| 495 | |
| 496 | func TestLeavingTheAlternateScreenBringsBackTheHistory(t *testing.T) { |
| 497 | s := NewScreen(10, 2) |
| 498 | for _, text := range []string{"one", "two", "three"} { |
| 499 | writeString(s, text) |
| 500 | s.CarriageReturn() |
| 501 | s.LineFeed() |
| 502 | } |
| 503 | before := s.ScrollbackLen() |
| 504 | |
| 505 | s.UseAlternate(true) |
| 506 | s.UseAlternate(false) |
| 507 | |
| 508 | if got := s.ScrollbackLen(); got != before { |
| 509 | t.Errorf("ScrollbackLen() = %d, want the %d lines from before", got, before) |
| 510 | } |
| 511 | } |
| 512 | |
| 513 | func TestResizeKeepsWhatFits(t *testing.T) { |
| 514 | s := NewScreen(10, 3) |
| 515 | for row, text := range []string{"one", "two", "three"} { |
| 516 | s.MoveTo(row, 0) |
| 517 | writeString(s, text) |
| 518 | } |
| 519 | |
| 520 | s.Resize(20, 5) |
| 521 | |
| 522 | if width, height := s.Size(); width != 20 || height != 5 { |
| 523 | t.Fatalf("Size() = %dx%d, want 20x5", width, height) |
| 524 | } |
| 525 | wantLines(t, s, "one", "two", "three", "", "") |
| 526 | } |
| 527 | |
| 528 | func TestShrinkingKeepsTheNewestLinesAndRemembersTheRest(t *testing.T) { |
| 529 | s := NewScreen(10, 4) |
| 530 | for row, text := range []string{"one", "two", "three", "four"} { |
| 531 | s.MoveTo(row, 0) |
| 532 | writeString(s, text) |
| 533 | } |
| 534 | |
| 535 | s.Resize(10, 2) |
| 536 | |
| 537 | wantLines(t, s, "three", "four") |
| 538 | if got := s.ScrollbackLen(); got != 2 { |
| 539 | t.Fatalf("ScrollbackLen() = %d, want the two lost lines kept", got) |
| 540 | } |
| 541 | if got := lineText(s.ScrollbackLine(0)); got != "one" { |
| 542 | t.Errorf("the oldest remembered line is %q, want %q", got, "one") |
| 543 | } |
| 544 | } |
| 545 | |
| 546 | func TestShrinkingAMostlyEmptyScreenKeepsWhatIsOnIt(t *testing.T) { |
| 547 | // A command that prints one line and exits leaves the cursor near the top |
| 548 | // and the rest of the screen blank. Dropping rows from the top to make |
| 549 | // room then throws the output away while keeping blank rows below it — |
| 550 | // which is how "echo TADA" in a tool window showed nothing at all. |
| 551 | s := NewScreen(20, 24) |
| 552 | writeString(s, "TADA") |
| 553 | s.LineFeed() |
| 554 | s.CarriageReturn() |
| 555 | |
| 556 | s.Resize(20, 20) |
| 557 | |
| 558 | if got := lineText(s.Line(0)); got != "TADA" { |
| 559 | t.Errorf("the first row is %q, want the output still on screen", got) |
| 560 | } |
| 561 | if got := s.ScrollbackLen(); got != 0 { |
| 562 | t.Errorf("ScrollbackLen() = %d; nothing had scrolled off, so nothing should be remembered", got) |
| 563 | } |
| 564 | } |
| 565 | |
| 566 | func TestShrinkingDropsOnlyAsManyRowsAsTheCursorNeeds(t *testing.T) { |
| 567 | // Halfway between the two cases: content down to row 5, cursor on row 5, |
| 568 | // shrunk to 4 rows. Two rows have to go for the cursor to fit, and only |
| 569 | // two should. |
| 570 | s := NewScreen(10, 10) |
| 571 | for row, text := range []string{"a", "b", "c", "d", "e", "f"} { |
| 572 | s.MoveTo(row, 0) |
| 573 | writeString(s, text) |
| 574 | } |
| 575 | |
| 576 | s.Resize(10, 4) |
| 577 | |
| 578 | wantLines(t, s, "c", "d", "e", "f") |
| 579 | if got := s.ScrollbackLen(); got != 2 { |
| 580 | t.Errorf("ScrollbackLen() = %d, want the two rows above the kept ones", got) |
| 581 | } |
| 582 | } |
| 583 | |
| 584 | func TestNarrowingCutsColumnsRatherThanReflowing(t *testing.T) { |
| 585 | // No terminal reflows on resize, and pretending to would move text the |
| 586 | // program believes it has already placed. |
| 587 | s := NewScreen(10, 2) |
| 588 | writeString(s, "abcdefghij") |
| 589 | |
| 590 | s.Resize(4, 2) |
| 591 | |
| 592 | wantLines(t, s, "abcd") |
| 593 | } |
| 594 | |
| 595 | func TestResizingToTheSameSizeChangesNothing(t *testing.T) { |
| 596 | s := NewScreen(10, 3) |
| 597 | writeString(s, "kept") |
| 598 | s.MoveTo(2, 5) |
| 599 | |
| 600 | s.Resize(10, 3) |
| 601 | |
| 602 | wantLines(t, s, "kept") |
| 603 | if got := s.Cursor(); got != (Cursor{Row: 2, Col: 5}) { |
| 604 | t.Errorf("Cursor() = %+v, want it untouched", got) |
| 605 | } |
| 606 | } |
| 607 | |
| 608 | func TestResizingWhileOnTheAlternateScreenKeepsThePrimaryUsable(t *testing.T) { |
| 609 | s := NewScreen(10, 3) |
| 610 | writeString(s, "primary") |
| 611 | s.UseAlternate(true) |
| 612 | |
| 613 | s.Resize(20, 6) |
| 614 | s.UseAlternate(false) |
| 615 | |
| 616 | if width, height := s.Size(); width != 20 || height != 6 { |
| 617 | t.Fatalf("Size() = %dx%d, want 20x6", width, height) |
| 618 | } |
| 619 | wantLines(t, s, "primary") |
| 620 | if got := len(s.Line(0)); got != 20 { |
| 621 | t.Errorf("the restored line is %d cells wide, want 20", got) |
| 622 | } |
| 623 | } |
| 624 | |
| 625 | func TestResizeClampsTheCursor(t *testing.T) { |
| 626 | s := NewScreen(10, 5) |
| 627 | s.MoveTo(4, 9) |
| 628 | |
| 629 | s.Resize(4, 2) |
| 630 | |
| 631 | got := s.Cursor() |
| 632 | if got.Row > 1 || got.Col > 3 { |
| 633 | t.Errorf("Cursor() = %+v, want it inside a 4x2 screen", got) |
| 634 | } |
| 635 | } |
| 636 | |
| 637 | func TestResetPutsEverythingBack(t *testing.T) { |
| 638 | s := NewScreen(10, 3) |
| 639 | writeString(s, "text") |
| 640 | s.SetStyle(tcell.StyleDefault.Bold(true)) |
| 641 | s.SetScrollRegion(1, 2) |
| 642 | s.SetCursorVisible(false) |
| 643 | s.UseAlternate(true) |
| 644 | |
| 645 | s.Reset() |
| 646 | |
| 647 | wantLines(t, s, "", "", "") |
| 648 | if s.Alternate() { |
| 649 | t.Error("Alternate() = true after a reset") |
| 650 | } |
| 651 | if !s.CursorVisible() { |
| 652 | t.Error("CursorVisible() = false after a reset") |
| 653 | } |
| 654 | if got := s.Cursor(); got != (Cursor{}) { |
| 655 | t.Errorf("Cursor() = %+v, want the top left", got) |
| 656 | } |
| 657 | if _, _, attrs := s.Style().Decompose(); attrs&tcell.AttrBold != 0 { |
| 658 | t.Error("the style survived a reset") |
| 659 | } |
| 660 | } |
| 661 | |
| 662 | func TestCellAtAndLineOutsideTheScreen(t *testing.T) { |
| 663 | s := NewScreen(4, 2) |
| 664 | |
| 665 | if got := s.CellAt(99, 0).Rune; got != ' ' { |
| 666 | t.Errorf("CellAt off the screen gave %q, want a space", got) |
| 667 | } |
| 668 | if s.Line(-1) != nil || s.Line(99) != nil { |
| 669 | t.Error("Line off the screen returned something") |
| 670 | } |
| 671 | if got := s.LineText(99); got != "" { |
| 672 | t.Errorf("LineText off the screen gave %q", got) |
| 673 | } |
| 674 | } |
| 675 | |
| 676 | func TestErasingKeepsTheCurrentBackground(t *testing.T) { |
| 677 | // A program painting a coloured panel and then clearing a line inside it |
| 678 | // expects the panel's colour to stay, not a hole. |
| 679 | s := NewScreen(5, 2) |
| 680 | panel := tcell.StyleDefault.Background(tcell.ColorNavy) |
| 681 | s.SetStyle(panel) |
| 682 | |
| 683 | s.EraseLine(EraseAll) |
| 684 | |
| 685 | if _, background, _ := s.CellAt(0, 0).Style.Decompose(); background != tcell.ColorNavy { |
| 686 | t.Errorf("the erased cell has background %v, want navy", background) |
| 687 | } |
| 688 | } |
| 689 | |
| 690 | // lineText renders a line as a string with its trailing blanks removed. |
| 691 | func lineText(line Line) string { |
| 692 | var out strings.Builder |
| 693 | for _, cell := range line { |
| 694 | out.WriteRune(cell.Rune) |
| 695 | } |
| 696 | return strings.TrimRight(out.String(), " ") |
| 697 | } |