t/t6036-recursive-corner-cases.sh

   1 #!/bin/sh
   2
   3 test_description='recursive merge corner cases involving criss-cross merges'
   4
   5 . ./test-lib.sh
   6
   7 get_clean_checkout () {
   8         git reset --hard &&
   9         git clean -fdqx &&
  10         git checkout "$1"
  11 }
  12
  13 #
  14 #  L1  L2
  15 #   o---o
  16 #  / \ / \
  17 # o   X   ?
  18 #  \ / \ /
  19 #   o---o
  20 #  R1  R2
  21 #
  22
  23 test_expect_success 'setup basic criss-cross + rename with no modifications' '
  24         ten="0 1 2 3 4 5 6 7 8 9" &&
  25         for i in $ten
  26         do
  27                 echo line $i in a sample file
  28         done >one &&
  29         for i in $ten
  30         do
  31                 echo line $i in another sample file
  32         done >two &&
  33         git add one two &&
  34         test_tick && git commit -m initial &&
  35
  36         git branch L1 &&
  37         git checkout -b R1 &&
  38         git mv one three &&
  39         test_tick && git commit -m R1 &&
  40
  41         git checkout L1 &&
  42         git mv two three &&
  43         test_tick && git commit -m L1 &&
  44
  45         git checkout L1^0 &&
  46         test_tick && git merge -s ours R1 &&
  47         git tag L2 &&
  48
  49         git checkout R1^0 &&
  50         test_tick && git merge -s ours L1 &&
  51         git tag R2
  52 '
  53
  54 test_expect_success 'merge simple rename+criss-cross with no modifications' '
  55         git reset --hard &&
  56         git checkout L2^0 &&
  57
  58         test_must_fail git merge -s recursive R2^0 &&
  59
  60         test 2 = $(git ls-files -s | wc -l) &&
  61         test 2 = $(git ls-files -u | wc -l) &&
  62         test 2 = $(git ls-files -o | wc -l) &&
  63
  64         test $(git rev-parse :2:three) = $(git rev-parse L2:three) &&
  65         test $(git rev-parse :3:three) = $(git rev-parse R2:three) &&
  66
  67         test $(git rev-parse L2:three) = $(git hash-object three~HEAD) &&
  68         test $(git rev-parse R2:three) = $(git hash-object three~R2^0)
  69 '
  70
  71 #
  72 # Same as before, but modify L1 slightly:
  73 #
  74 #  L1m L2
  75 #   o---o
  76 #  / \ / \
  77 # o   X   ?
  78 #  \ / \ /
  79 #   o---o
  80 #  R1  R2
  81 #
  82
  83 test_expect_success 'setup criss-cross + rename merges with basic modification' '
  84         git rm -rf . &&
  85         git clean -fdqx &&
  86         rm -rf .git &&
  87         git init &&
  88
  89         ten="0 1 2 3 4 5 6 7 8 9" &&
  90         for i in $ten
  91         do
  92                 echo line $i in a sample file
  93         done >one &&
  94         for i in $ten
  95         do
  96                 echo line $i in another sample file
  97         done >two &&
  98         git add one two &&
  99         test_tick && git commit -m initial &&
 100
 101         git branch L1 &&
 102         git checkout -b R1 &&
 103         git mv one three &&
 104         echo more >>two &&
 105         git add two &&
 106         test_tick && git commit -m R1 &&
 107
 108         git checkout L1 &&
 109         git mv two three &&
 110         test_tick && git commit -m L1 &&
 111
 112         git checkout L1^0 &&
 113         test_tick && git merge -s ours R1 &&
 114         git tag L2 &&
 115
 116         git checkout R1^0 &&
 117         test_tick && git merge -s ours L1 &&
 118         git tag R2
 119 '
 120
 121 test_expect_success 'merge criss-cross + rename merges with basic modification' '
 122         git reset --hard &&
 123         git checkout L2^0 &&
 124
 125         test_must_fail git merge -s recursive R2^0 &&
 126
 127         test 2 = $(git ls-files -s | wc -l) &&
 128         test 2 = $(git ls-files -u | wc -l) &&
 129         test 2 = $(git ls-files -o | wc -l) &&
 130
 131         test $(git rev-parse :2:three) = $(git rev-parse L2:three) &&
 132         test $(git rev-parse :3:three) = $(git rev-parse R2:three) &&
 133
 134         test $(git rev-parse L2:three) = $(git hash-object three~HEAD) &&
 135         test $(git rev-parse R2:three) = $(git hash-object three~R2^0)
 136 '
 137
 138 #
 139 # For the next test, we start with three commits in two lines of development
 140 # which setup a rename/add conflict:
 141 #   Commit A: File 'a' exists
 142 #   Commit B: Rename 'a' -> 'new_a'
 143 #   Commit C: Modify 'a', create different 'new_a'
 144 # Later, two different people merge and resolve differently:
 145 #   Commit D: Merge B & C, ignoring separately created 'new_a'
 146 #   Commit E: Merge B & C making use of some piece of secondary 'new_a'
 147 # Finally, someone goes to merge D & E.  Does git detect the conflict?
 148 #
 149 #      B   D
 150 #      o---o
 151 #     / \ / \
 152 #  A o   X   ? F
 153 #     \ / \ /
 154 #      o---o
 155 #      C   E
 156 #
 157
 158 test_expect_success 'setup differently handled merges of rename/add conflict' '
 159         git rm -rf . &&
 160         git clean -fdqx &&
 161         rm -rf .git &&
 162         git init &&
 163
 164         printf "0\n1\n2\n3\n4\n5\n6\n7\n8\n9\n" >a &&
 165         git add a &&
 166         test_tick && git commit -m A &&
 167
 168         git branch B &&
 169         git checkout -b C &&
 170         echo 10 >>a &&
 171         echo "other content" >>new_a &&
 172         git add a new_a &&
 173         test_tick && git commit -m C &&
 174
 175         git checkout B &&
 176         git mv a new_a &&
 177         test_tick && git commit -m B &&
 178
 179         git checkout B^0 &&
 180         test_must_fail git merge C &&
 181         git clean -f &&
 182         test_tick && git commit -m D &&
 183         git tag D &&
 184
 185         git checkout C^0 &&
 186         test_must_fail git merge B &&
 187         rm new_a~HEAD new_a &&
 188         printf "Incorrectly merged content" >>new_a &&
 189         git add -u &&
 190         test_tick && git commit -m E &&
 191         git tag E
 192 '
 193
 194 test_expect_success 'git detects differently handled merges conflict' '
 195         git reset --hard &&
 196         git checkout D^0 &&
 197
 198         test_must_fail git merge -s recursive E^0 &&
 199
 200         test 3 = $(git ls-files -s | wc -l) &&
 201         test 3 = $(git ls-files -u | wc -l) &&
 202         test 0 = $(git ls-files -o | wc -l) &&
 203
 204         test $(git rev-parse :2:new_a) = $(git rev-parse D:new_a) &&
 205         test $(git rev-parse :3:new_a) = $(git rev-parse E:new_a) &&
 206
 207         git cat-file -p B:new_a >>merged &&
 208         git cat-file -p C:new_a >>merge-me &&
 209         >empty &&
 210         test_must_fail git merge-file \
 211                 -L "Temporary merge branch 2" \
 212                 -L "" \
 213                 -L "Temporary merge branch 1" \
 214                 merged empty merge-me &&
 215         sed -e "s/^\([<=>]\)/\1\1\1/" merged >merged-internal &&
 216         test $(git rev-parse :1:new_a) = $(git hash-object merged-internal)
 217 '
 218
 219 #
 220 # criss-cross + modify/delete:
 221 #
 222 #      B   D
 223 #      o---o
 224 #     / \ / \
 225 #  A o   X   ? F
 226 #     \ / \ /
 227 #      o---o
 228 #      C   E
 229 #
 230 #   Commit A: file with contents 'A\n'
 231 #   Commit B: file with contents 'B\n'
 232 #   Commit C: file not present
 233 #   Commit D: file with contents 'B\n'
 234 #   Commit E: file not present
 235 #
 236 # Merging commits D & E should result in modify/delete conflict.
 237
 238 test_expect_success 'setup criss-cross + modify/delete resolved differently' '
 239         git rm -rf . &&
 240         git clean -fdqx &&
 241         rm -rf .git &&
 242         git init &&
 243
 244         echo A >file &&
 245         git add file &&
 246         test_tick &&
 247         git commit -m A &&
 248
 249         git branch B &&
 250         git checkout -b C &&
 251         git rm file &&
 252         test_tick &&
 253         git commit -m C &&
 254
 255         git checkout B &&
 256         echo B >file &&
 257         git add file &&
 258         test_tick &&
 259         git commit -m B &&
 260
 261         git checkout B^0 &&
 262         test_must_fail git merge C &&
 263         echo B >file &&
 264         git add file &&
 265         test_tick &&
 266         git commit -m D &&
 267         git tag D &&
 268
 269         git checkout C^0 &&
 270         test_must_fail git merge B &&
 271         git rm file &&
 272         test_tick &&
 273         git commit -m E &&
 274         git tag E
 275 '
 276
 277 test_expect_success 'git detects conflict merging criss-cross+modify/delete' '
 278         git checkout D^0 &&
 279
 280         test_must_fail git merge -s recursive E^0 &&
 281
 282         test 2 -eq $(git ls-files -s | wc -l) &&
 283         test 2 -eq $(git ls-files -u | wc -l) &&
 284
 285         test $(git rev-parse :1:file) = $(git rev-parse master:file) &&
 286         test $(git rev-parse :2:file) = $(git rev-parse B:file)
 287 '
 288
 289 test_expect_success 'git detects conflict merging criss-cross+modify/delete, reverse direction' '
 290         git reset --hard &&
 291         git checkout E^0 &&
 292
 293         test_must_fail git merge -s recursive D^0 &&
 294
 295         test 2 -eq $(git ls-files -s | wc -l) &&
 296         test 2 -eq $(git ls-files -u | wc -l) &&
 297
 298         test $(git rev-parse :1:file) = $(git rev-parse master:file) &&
 299         test $(git rev-parse :3:file) = $(git rev-parse B:file)
 300 '
 301
 302 #
 303 # criss-cross + d/f conflict via add/add:
 304 #   Commit A: Neither file 'a' nor directory 'a/' exists.
 305 #   Commit B: Introduce 'a'
 306 #   Commit C: Introduce 'a/file'
 307 #   Commit D: Merge B & C, keeping 'a' and deleting 'a/'
 308 #
 309 # Two different later cases:
 310 #   Commit E1: Merge B & C, deleting 'a' but keeping 'a/file'
 311 #   Commit E2: Merge B & C, deleting 'a' but keeping a slightly modified 'a/file'
 312 #
 313 #      B   D
 314 #      o---o
 315 #     / \ / \
 316 #  A o   X   ? F
 317 #     \ / \ /
 318 #      o---o
 319 #      C   E1 or E2
 320 #
 321 # Merging D & E1 requires we first create a virtual merge base X from
 322 # merging A & B in memory.  Now, if X could keep both 'a' and 'a/file' in
 323 # the index, then the merge of D & E1 could be resolved cleanly with both
 324 # 'a' and 'a/file' removed.  Since git does not currently allow creating
 325 # such a tree, the best we can do is have X contain both 'a~<unique>' and
 326 # 'a/file' resulting in the merge of D and E1 having a rename/delete
 327 # conflict for 'a'.  (Although this merge appears to be unsolvable with git
 328 # currently, git could do a lot better than it currently does with these
 329 # d/f conflicts, which is the purpose of this test.)
 330 #
 331 # Merge of D & E2 has similar issues for path 'a', but should always result
 332 # in a modify/delete conflict for path 'a/file'.
 333 #
 334 # We run each merge in both directions, to check for directional issues
 335 # with D/F conflict handling.
 336 #
 337
 338 test_expect_success 'setup differently handled merges of directory/file conflict' '
 339         git rm -rf . &&
 340         git clean -fdqx &&
 341         rm -rf .git &&
 342         git init &&
 343
 344         >ignore-me &&
 345         git add ignore-me &&
 346         test_tick &&
 347         git commit -m A &&
 348         git tag A &&
 349
 350         git branch B &&
 351         git checkout -b C &&
 352         mkdir a &&
 353         echo 10 >a/file &&
 354         git add a/file &&
 355         test_tick &&
 356         git commit -m C &&
 357
 358         git checkout B &&
 359         echo 5 >a &&
 360         git add a &&
 361         test_tick &&
 362         git commit -m B &&
 363
 364         git checkout B^0 &&
 365         test_must_fail git merge C &&
 366         git clean -f &&
 367         rm -rf a/ &&
 368         echo 5 >a &&
 369         git add a &&
 370         test_tick &&
 371         git commit -m D &&
 372         git tag D &&
 373
 374         git checkout C^0 &&
 375         test_must_fail git merge B &&
 376         git clean -f &&
 377         git rm --cached a &&
 378         echo 10 >a/file &&
 379         git add a/file &&
 380         test_tick &&
 381         git commit -m E1 &&
 382         git tag E1 &&
 383
 384         git checkout C^0 &&
 385         test_must_fail git merge B &&
 386         git clean -f &&
 387         git rm --cached a &&
 388         printf "10\n11\n" >a/file &&
 389         git add a/file &&
 390         test_tick &&
 391         git commit -m E2 &&
 392         git tag E2
 393 '
 394
 395 test_expect_success 'merge of D & E1 fails but has appropriate contents' '
 396         get_clean_checkout D^0 &&
 397
 398         test_must_fail git merge -s recursive E1^0 &&
 399
 400         test 2 -eq $(git ls-files -s | wc -l) &&
 401         test 1 -eq $(git ls-files -u | wc -l) &&
 402         test 0 -eq $(git ls-files -o | wc -l) &&
 403
 404         test $(git rev-parse :0:ignore-me) = $(git rev-parse A:ignore-me) &&
 405         test $(git rev-parse :2:a) = $(git rev-parse B:a)
 406 '
 407
 408 test_expect_success 'merge of E1 & D fails but has appropriate contents' '
 409         get_clean_checkout E1^0 &&
 410
 411         test_must_fail git merge -s recursive D^0 &&
 412
 413         test 2 -eq $(git ls-files -s | wc -l) &&
 414         test 1 -eq $(git ls-files -u | wc -l) &&
 415         test 0 -eq $(git ls-files -o | wc -l) &&
 416
 417         test $(git rev-parse :0:ignore-me) = $(git rev-parse A:ignore-me) &&
 418         test $(git rev-parse :3:a) = $(git rev-parse B:a)
 419 '
 420
 421 test_expect_success 'merge of D & E2 fails but has appropriate contents' '
 422         get_clean_checkout D^0 &&
 423
 424         test_must_fail git merge -s recursive E2^0 &&
 425
 426         test 4 -eq $(git ls-files -s | wc -l) &&
 427         test 3 -eq $(git ls-files -u | wc -l) &&
 428         test 1 -eq $(git ls-files -o | wc -l) &&
 429
 430         test $(git rev-parse :2:a) = $(git rev-parse B:a) &&
 431         test $(git rev-parse :3:a/file) = $(git rev-parse E2:a/file) &&
 432         test $(git rev-parse :1:a/file) = $(git rev-parse C:a/file) &&
 433         test $(git rev-parse :0:ignore-me) = $(git rev-parse A:ignore-me) &&
 434
 435         test -f a~HEAD
 436 '
 437
 438 test_expect_success 'merge of E2 & D fails but has appropriate contents' '
 439         get_clean_checkout E2^0 &&
 440
 441         test_must_fail git merge -s recursive D^0 &&
 442
 443         test 4 -eq $(git ls-files -s | wc -l) &&
 444         test 3 -eq $(git ls-files -u | wc -l) &&
 445         test 1 -eq $(git ls-files -o | wc -l) &&
 446
 447         test $(git rev-parse :3:a) = $(git rev-parse B:a) &&
 448         test $(git rev-parse :2:a/file) = $(git rev-parse E2:a/file) &&
 449         test $(git rev-parse :1:a/file) = $(git rev-parse C:a/file) &&
 450         test $(git rev-parse :0:ignore-me) = $(git rev-parse A:ignore-me) &&
 451
 452         test -f a~D^0
 453 '
 454
 455 #
 456 # criss-cross with rename/rename(1to2)/modify followed by
 457 # rename/rename(2to1)/modify:
 458 #
 459 #      B   D
 460 #      o---o
 461 #     / \ / \
 462 #  A o   X   ? F
 463 #     \ / \ /
 464 #      o---o
 465 #      C   E
 466 #
 467 #   Commit A: new file: a
 468 #   Commit B: rename a->b, modifying by adding a line
 469 #   Commit C: rename a->c
 470 #   Commit D: merge B&C, resolving conflict by keeping contents in newname
 471 #   Commit E: merge B&C, resolving conflict similar to D but adding another line
 472 #
 473 # There is a conflict merging B & C, but one of filename not of file
 474 # content.  Whoever created D and E chose specific resolutions for that
 475 # conflict resolution.  Now, since: (1) there is no content conflict
 476 # merging B & C, (2) D does not modify that merged content further, and (3)
 477 # both D & E resolve the name conflict in the same way, the modification to
 478 # newname in E should not cause any conflicts when it is merged with D.
 479 # (Note that this can be accomplished by having the virtual merge base have
 480 # the merged contents of b and c stored in a file named a, which seems like
 481 # the most logical choice anyway.)
 482 #
 483 # Comment from Junio: I do not necessarily agree with the choice "a", but
 484 # it feels sound to say "B and C do not agree what the final pathname
 485 # should be, but we know this content was derived from the common A:a so we
 486 # use one path whose name is arbitrary in the virtual merge base X between
 487 # D and E" and then further let the rename detection to notice that that
 488 # arbitrary path gets renamed between X-D to "newname" and X-E also to
 489 # "newname" to resolve it as both sides renaming it to the same new
 490 # name. It is akin to what we do at the content level, i.e. "B and C do not
 491 # agree what the final contents should be, so we leave the conflict marker
 492 # but that may cancel out at the final merge stage".
 493
 494 test_expect_success 'setup rename/rename(1to2)/modify followed by what looks like rename/rename(2to1)/modify' '
 495         git reset --hard &&
 496         git rm -rf . &&
 497         git clean -fdqx &&
 498         rm -rf .git &&
 499         git init &&
 500
 501         printf "1\n2\n3\n4\n5\n6\n" >a &&
 502         git add a &&
 503         git commit -m A &&
 504         git tag A &&
 505
 506         git checkout -b B A &&
 507         git mv a b &&
 508         echo 7 >>b &&
 509         git add -u &&
 510         git commit -m B &&
 511
 512         git checkout -b C A &&
 513         git mv a c &&
 514         git commit -m C &&
 515
 516         git checkout -q B^0 &&
 517         git merge --no-commit -s ours C^0 &&
 518         git mv b newname &&
 519         git commit -m "Merge commit C^0 into HEAD" &&
 520         git tag D &&
 521
 522         git checkout -q C^0 &&
 523         git merge --no-commit -s ours B^0 &&
 524         git mv c newname &&
 525         printf "7\n8\n" >>newname &&
 526         git add -u &&
 527         git commit -m "Merge commit B^0 into HEAD" &&
 528         git tag E
 529 '
 530
 531 test_expect_success 'handle rename/rename(1to2)/modify followed by what looks like rename/rename(2to1)/modify' '
 532         git checkout D^0 &&
 533
 534         git merge -s recursive E^0 &&
 535
 536         test 1 -eq $(git ls-files -s | wc -l) &&
 537         test 0 -eq $(git ls-files -u | wc -l) &&
 538         test 0 -eq $(git ls-files -o | wc -l) &&
 539
 540         test $(git rev-parse HEAD:newname) = $(git rev-parse E:newname)
 541 '
 542
 543 #
 544 # criss-cross with rename/rename(1to2)/add-source + resolvable modify/modify:
 545 #
 546 #      B   D
 547 #      o---o
 548 #     / \ / \
 549 #  A o   X   ? F
 550 #     \ / \ /
 551 #      o---o
 552 #      C   E
 553 #
 554 #   Commit A: new file: a
 555 #   Commit B: rename a->b
 556 #   Commit C: rename a->c, add different a
 557 #   Commit D: merge B&C, keeping b&c and (new) a modified at beginning
 558 #   Commit E: merge B&C, keeping b&c and (new) a modified at end
 559 #
 560 # Merging commits D & E should result in no conflict; doing so correctly
 561 # requires getting the virtual merge base (from merging B&C) right, handling
 562 # renaming carefully (both in the virtual merge base and later), and getting
 563 # content merge handled.
 564
 565 test_expect_success 'setup criss-cross + rename/rename/add + modify/modify' '
 566         git rm -rf . &&
 567         git clean -fdqx &&
 568         rm -rf .git &&
 569         git init &&
 570
 571         printf "lots\nof\nwords\nand\ncontent\n" >a &&
 572         git add a &&
 573         git commit -m A &&
 574         git tag A &&
 575
 576         git checkout -b B A &&
 577         git mv a b &&
 578         git commit -m B &&
 579
 580         git checkout -b C A &&
 581         git mv a c &&
 582         printf "2\n3\n4\n5\n6\n7\n" >a &&
 583         git add a &&
 584         git commit -m C &&
 585
 586         git checkout B^0 &&
 587         git merge --no-commit -s ours C^0 &&
 588         git checkout C -- a c &&
 589         mv a old_a &&
 590         echo 1 >a &&
 591         cat old_a >>a &&
 592         rm old_a &&
 593         git add -u &&
 594         git commit -m "Merge commit C^0 into HEAD" &&
 595         git tag D &&
 596
 597         git checkout C^0 &&
 598         git merge --no-commit -s ours B^0 &&
 599         git checkout B -- b &&
 600         echo 8 >>a &&
 601         git add -u &&
 602         git commit -m "Merge commit B^0 into HEAD" &&
 603         git tag E
 604 '
 605
 606 test_expect_failure 'detect rename/rename/add-source for virtual merge-base' '
 607         git checkout D^0 &&
 608
 609         git merge -s recursive E^0 &&
 610
 611         test 3 -eq $(git ls-files -s | wc -l) &&
 612         test 0 -eq $(git ls-files -u | wc -l) &&
 613         test 0 -eq $(git ls-files -o | wc -l) &&
 614
 615         test $(git rev-parse HEAD:b) = $(git rev-parse A:a) &&
 616         test $(git rev-parse HEAD:c) = $(git rev-parse A:a) &&
 617         test "$(cat a)" = "$(printf "1\n2\n3\n4\n5\n6\n7\n8\n")"
 618 '
 619
 620 #
 621 # criss-cross with rename/rename(1to2)/add-dest + simple modify:
 622 #
 623 #      B   D
 624 #      o---o
 625 #     / \ / \
 626 #  A o   X   ? F
 627 #     \ / \ /
 628 #      o---o
 629 #      C   E
 630 #
 631 #   Commit A: new file: a
 632 #   Commit B: rename a->b, add c
 633 #   Commit C: rename a->c
 634 #   Commit D: merge B&C, keeping A:a and B:c
 635 #   Commit E: merge B&C, keeping A:a and slightly modified c from B
 636 #
 637 # Merging commits D & E should result in no conflict.  The virtual merge
 638 # base of B & C needs to not delete B:c for that to work, though...
 639
 640 test_expect_success 'setup criss-cross+rename/rename/add-dest + simple modify' '
 641         git rm -rf . &&
 642         git clean -fdqx &&
 643         rm -rf .git &&
 644         git init &&
 645
 646         >a &&
 647         git add a &&
 648         git commit -m A &&
 649         git tag A &&
 650
 651         git checkout -b B A &&
 652         git mv a b &&
 653         printf "1\n2\n3\n4\n5\n6\n7\n" >c &&
 654         git add c &&
 655         git commit -m B &&
 656
 657         git checkout -b C A &&
 658         git mv a c &&
 659         git commit -m C &&
 660
 661         git checkout B^0 &&
 662         git merge --no-commit -s ours C^0 &&
 663         git mv b a &&
 664         git commit -m "D is like B but renames b back to a" &&
 665         git tag D &&
 666
 667         git checkout B^0 &&
 668         git merge --no-commit -s ours C^0 &&
 669         git mv b a &&
 670         echo 8 >>c &&
 671         git add c &&
 672         git commit -m "E like D but has mod in c" &&
 673         git tag E
 674 '
 675
 676 test_expect_success 'virtual merge base handles rename/rename(1to2)/add-dest' '
 677         git checkout D^0 &&
 678
 679         git merge -s recursive E^0 &&
 680
 681         test 2 -eq $(git ls-files -s | wc -l) &&
 682         test 0 -eq $(git ls-files -u | wc -l) &&
 683         test 0 -eq $(git ls-files -o | wc -l) &&
 684
 685         test $(git rev-parse HEAD:a) = $(git rev-parse A:a) &&
 686         test $(git rev-parse HEAD:c) = $(git rev-parse E:c)
 687 '
 688
 689 test_done