t / t6043-merge-rename-directories.shon commit directory rename detection: more involved edge/corner testcases (f95de96)
   1#!/bin/sh
   2
   3test_description="recursive merge with directory renames"
   4# includes checking of many corner cases, with a similar methodology to:
   5#   t6042: corner cases with renames but not criss-cross merges
   6#   t6036: corner cases with both renames and criss-cross merges
   7#
   8# The setup for all of them, pictorially, is:
   9#
  10#      A
  11#      o
  12#     / \
  13#  O o   ?
  14#     \ /
  15#      o
  16#      B
  17#
  18# To help make it easier to follow the flow of tests, they have been
  19# divided into sections and each test will start with a quick explanation
  20# of what commits O, A, and B contain.
  21#
  22# Notation:
  23#    z/{b,c}   means  files z/b and z/c both exist
  24#    x/d_1     means  file x/d exists with content d1.  (Purpose of the
  25#                     underscore notation is to differentiate different
  26#                     files that might be renamed into each other's paths.)
  27
  28. ./test-lib.sh
  29
  30
  31###########################################################################
  32# SECTION 1: Basic cases we should be able to handle
  33###########################################################################
  34
  35# Testcase 1a, Basic directory rename.
  36#   Commit O: z/{b,c}
  37#   Commit A: y/{b,c}
  38#   Commit B: z/{b,c,d,e/f}
  39#   Expected: y/{b,c,d,e/f}
  40
  41test_expect_success '1a-setup: Simple directory rename detection' '
  42        test_create_repo 1a &&
  43        (
  44                cd 1a &&
  45
  46                mkdir z &&
  47                echo b >z/b &&
  48                echo c >z/c &&
  49                git add z &&
  50                test_tick &&
  51                git commit -m "O" &&
  52
  53                git branch O &&
  54                git branch A &&
  55                git branch B &&
  56
  57                git checkout A &&
  58                git mv z y &&
  59                test_tick &&
  60                git commit -m "A" &&
  61
  62                git checkout B &&
  63                echo d >z/d &&
  64                mkdir z/e &&
  65                echo f >z/e/f &&
  66                git add z/d z/e/f &&
  67                test_tick &&
  68                git commit -m "B"
  69        )
  70'
  71
  72test_expect_failure '1a-check: Simple directory rename detection' '
  73        (
  74                cd 1a &&
  75
  76                git checkout A^0 &&
  77
  78                git merge -s recursive B^0 &&
  79
  80                git ls-files -s >out &&
  81                test_line_count = 4 out &&
  82
  83                git rev-parse >actual \
  84                        HEAD:y/b HEAD:y/c HEAD:y/d HEAD:y/e/f &&
  85                git rev-parse >expect \
  86                        O:z/b    O:z/c    B:z/d    B:z/e/f &&
  87                test_cmp expect actual &&
  88
  89                git hash-object y/d >actual &&
  90                git rev-parse B:z/d >expect &&
  91                test_cmp expect actual &&
  92
  93                test_must_fail git rev-parse HEAD:z/d &&
  94                test_must_fail git rev-parse HEAD:z/e/f &&
  95                test_path_is_missing z/d &&
  96                test_path_is_missing z/e/f
  97        )
  98'
  99
 100# Testcase 1b, Merge a directory with another
 101#   Commit O: z/{b,c},   y/d
 102#   Commit A: z/{b,c,e}, y/d
 103#   Commit B: y/{b,c,d}
 104#   Expected: y/{b,c,d,e}
 105
 106test_expect_success '1b-setup: Merge a directory with another' '
 107        test_create_repo 1b &&
 108        (
 109                cd 1b &&
 110
 111                mkdir z &&
 112                echo b >z/b &&
 113                echo c >z/c &&
 114                mkdir y &&
 115                echo d >y/d &&
 116                git add z y &&
 117                test_tick &&
 118                git commit -m "O" &&
 119
 120                git branch O &&
 121                git branch A &&
 122                git branch B &&
 123
 124                git checkout A &&
 125                echo e >z/e &&
 126                git add z/e &&
 127                test_tick &&
 128                git commit -m "A" &&
 129
 130                git checkout B &&
 131                git mv z/b y &&
 132                git mv z/c y &&
 133                rmdir z &&
 134                test_tick &&
 135                git commit -m "B"
 136        )
 137'
 138
 139test_expect_failure '1b-check: Merge a directory with another' '
 140        (
 141                cd 1b &&
 142
 143                git checkout A^0 &&
 144
 145                git merge -s recursive B^0 &&
 146
 147                git ls-files -s >out &&
 148                test_line_count = 4 out &&
 149
 150                git rev-parse >actual \
 151                        HEAD:y/b HEAD:y/c HEAD:y/d HEAD:y/e &&
 152                git rev-parse >expect \
 153                        O:z/b    O:z/c    O:y/d    A:z/e &&
 154                test_cmp expect actual &&
 155                test_must_fail git rev-parse HEAD:z/e
 156        )
 157'
 158
 159# Testcase 1c, Transitive renaming
 160#   (Related to testcases 3a and 6d -- when should a transitive rename apply?)
 161#   (Related to testcases 9c and 9d -- can transitivity repeat?)
 162#   Commit O: z/{b,c},   x/d
 163#   Commit A: y/{b,c},   x/d
 164#   Commit B: z/{b,c,d}
 165#   Expected: y/{b,c,d}  (because x/d -> z/d -> y/d)
 166
 167test_expect_success '1c-setup: Transitive renaming' '
 168        test_create_repo 1c &&
 169        (
 170                cd 1c &&
 171
 172                mkdir z &&
 173                echo b >z/b &&
 174                echo c >z/c &&
 175                mkdir x &&
 176                echo d >x/d &&
 177                git add z x &&
 178                test_tick &&
 179                git commit -m "O" &&
 180
 181                git branch O &&
 182                git branch A &&
 183                git branch B &&
 184
 185                git checkout A &&
 186                git mv z y &&
 187                test_tick &&
 188                git commit -m "A" &&
 189
 190                git checkout B &&
 191                git mv x/d z/d &&
 192                test_tick &&
 193                git commit -m "B"
 194        )
 195'
 196
 197test_expect_failure '1c-check: Transitive renaming' '
 198        (
 199                cd 1c &&
 200
 201                git checkout A^0 &&
 202
 203                git merge -s recursive B^0 &&
 204
 205                git ls-files -s >out &&
 206                test_line_count = 3 out &&
 207
 208                git rev-parse >actual \
 209                        HEAD:y/b HEAD:y/c HEAD:y/d &&
 210                git rev-parse >expect \
 211                        O:z/b    O:z/c    O:x/d &&
 212                test_cmp expect actual &&
 213                test_must_fail git rev-parse HEAD:x/d &&
 214                test_must_fail git rev-parse HEAD:z/d &&
 215                test_path_is_missing z/d
 216        )
 217'
 218
 219# Testcase 1d, Directory renames (merging two directories into one new one)
 220#              cause a rename/rename(2to1) conflict
 221#   (Related to testcases 1c and 7b)
 222#   Commit O. z/{b,c},        y/{d,e}
 223#   Commit A. x/{b,c},        y/{d,e,m,wham_1}
 224#   Commit B. z/{b,c,n,wham_2}, x/{d,e}
 225#   Expected: x/{b,c,d,e,m,n}, CONFLICT:(y/wham_1 & z/wham_2 -> x/wham)
 226#   Note: y/m & z/n should definitely move into x.  By the same token, both
 227#         y/wham_1 & z/wham_2 should too...giving us a conflict.
 228
 229test_expect_success '1d-setup: Directory renames cause a rename/rename(2to1) conflict' '
 230        test_create_repo 1d &&
 231        (
 232                cd 1d &&
 233
 234                mkdir z &&
 235                echo b >z/b &&
 236                echo c >z/c &&
 237                mkdir y &&
 238                echo d >y/d &&
 239                echo e >y/e &&
 240                git add z y &&
 241                test_tick &&
 242                git commit -m "O" &&
 243
 244                git branch O &&
 245                git branch A &&
 246                git branch B &&
 247
 248                git checkout A &&
 249                git mv z x &&
 250                echo m >y/m &&
 251                echo wham1 >y/wham &&
 252                git add y &&
 253                test_tick &&
 254                git commit -m "A" &&
 255
 256                git checkout B &&
 257                git mv y x &&
 258                echo n >z/n &&
 259                echo wham2 >z/wham &&
 260                git add z &&
 261                test_tick &&
 262                git commit -m "B"
 263        )
 264'
 265
 266test_expect_failure '1d-check: Directory renames cause a rename/rename(2to1) conflict' '
 267        (
 268                cd 1d &&
 269
 270                git checkout A^0 &&
 271
 272                test_must_fail git merge -s recursive B^0 >out &&
 273                test_i18ngrep "CONFLICT (rename/rename)" out &&
 274
 275                git ls-files -s >out &&
 276                test_line_count = 8 out &&
 277                git ls-files -u >out &&
 278                test_line_count = 2 out &&
 279                git ls-files -o >out &&
 280                test_line_count = 3 out &&
 281
 282                git rev-parse >actual \
 283                        :0:x/b :0:x/c :0:x/d :0:x/e :0:x/m :0:x/n &&
 284                git rev-parse >expect \
 285                         O:z/b  O:z/c  O:y/d  O:y/e  A:y/m  B:z/n &&
 286                test_cmp expect actual &&
 287
 288                test_must_fail git rev-parse :0:x/wham &&
 289                git rev-parse >actual \
 290                        :2:x/wham :3:x/wham &&
 291                git rev-parse >expect \
 292                         A:y/wham  B:z/wham &&
 293                test_cmp expect actual &&
 294
 295                test_path_is_missing x/wham &&
 296                test_path_is_file x/wham~HEAD &&
 297                test_path_is_file x/wham~B^0 &&
 298
 299                git hash-object >actual \
 300                        x/wham~HEAD x/wham~B^0 &&
 301                git rev-parse >expect \
 302                        A:y/wham    B:z/wham &&
 303                test_cmp expect actual
 304        )
 305'
 306
 307# Testcase 1e, Renamed directory, with all filenames being renamed too
 308#   Commit O: z/{oldb,oldc}
 309#   Commit A: y/{newb,newc}
 310#   Commit B: z/{oldb,oldc,d}
 311#   Expected: y/{newb,newc,d}
 312
 313test_expect_success '1e-setup: Renamed directory, with all files being renamed too' '
 314        test_create_repo 1e &&
 315        (
 316                cd 1e &&
 317
 318                mkdir z &&
 319                echo b >z/oldb &&
 320                echo c >z/oldc &&
 321                git add z &&
 322                test_tick &&
 323                git commit -m "O" &&
 324
 325                git branch O &&
 326                git branch A &&
 327                git branch B &&
 328
 329                git checkout A &&
 330                mkdir y &&
 331                git mv z/oldb y/newb &&
 332                git mv z/oldc y/newc &&
 333                test_tick &&
 334                git commit -m "A" &&
 335
 336                git checkout B &&
 337                echo d >z/d &&
 338                git add z/d &&
 339                test_tick &&
 340                git commit -m "B"
 341        )
 342'
 343
 344test_expect_failure '1e-check: Renamed directory, with all files being renamed too' '
 345        (
 346                cd 1e &&
 347
 348                git checkout A^0 &&
 349
 350                git merge -s recursive B^0 &&
 351
 352                git ls-files -s >out &&
 353                test_line_count = 3 out &&
 354
 355                git rev-parse >actual \
 356                        HEAD:y/newb HEAD:y/newc HEAD:y/d &&
 357                git rev-parse >expect \
 358                        O:z/oldb    O:z/oldc    B:z/d &&
 359                test_cmp expect actual &&
 360                test_must_fail git rev-parse HEAD:z/d
 361        )
 362'
 363
 364# Testcase 1f, Split a directory into two other directories
 365#   (Related to testcases 3a, all of section 2, and all of section 4)
 366#   Commit O: z/{b,c,d,e,f}
 367#   Commit A: z/{b,c,d,e,f,g}
 368#   Commit B: y/{b,c}, x/{d,e,f}
 369#   Expected: y/{b,c}, x/{d,e,f,g}
 370
 371test_expect_success '1f-setup: Split a directory into two other directories' '
 372        test_create_repo 1f &&
 373        (
 374                cd 1f &&
 375
 376                mkdir z &&
 377                echo b >z/b &&
 378                echo c >z/c &&
 379                echo d >z/d &&
 380                echo e >z/e &&
 381                echo f >z/f &&
 382                git add z &&
 383                test_tick &&
 384                git commit -m "O" &&
 385
 386                git branch O &&
 387                git branch A &&
 388                git branch B &&
 389
 390                git checkout A &&
 391                echo g >z/g &&
 392                git add z/g &&
 393                test_tick &&
 394                git commit -m "A" &&
 395
 396                git checkout B &&
 397                mkdir y &&
 398                mkdir x &&
 399                git mv z/b y/ &&
 400                git mv z/c y/ &&
 401                git mv z/d x/ &&
 402                git mv z/e x/ &&
 403                git mv z/f x/ &&
 404                rmdir z &&
 405                test_tick &&
 406                git commit -m "B"
 407        )
 408'
 409
 410test_expect_failure '1f-check: Split a directory into two other directories' '
 411        (
 412                cd 1f &&
 413
 414                git checkout A^0 &&
 415
 416                git merge -s recursive B^0 &&
 417
 418                git ls-files -s >out &&
 419                test_line_count = 6 out &&
 420
 421                git rev-parse >actual \
 422                        HEAD:y/b HEAD:y/c HEAD:x/d HEAD:x/e HEAD:x/f HEAD:x/g &&
 423                git rev-parse >expect \
 424                        O:z/b    O:z/c    O:z/d    O:z/e    O:z/f    A:z/g &&
 425                test_cmp expect actual &&
 426                test_path_is_missing z/g &&
 427                test_must_fail git rev-parse HEAD:z/g
 428        )
 429'
 430
 431###########################################################################
 432# Rules suggested by testcases in section 1:
 433#
 434#   We should still detect the directory rename even if it wasn't just
 435#   the directory renamed, but the files within it. (see 1b)
 436#
 437#   If renames split a directory into two or more others, the directory
 438#   with the most renames, "wins" (see 1c).  However, see the testcases
 439#   in section 2, plus testcases 3a and 4a.
 440###########################################################################
 441
 442
 443###########################################################################
 444# SECTION 2: Split into multiple directories, with equal number of paths
 445#
 446# Explore the splitting-a-directory rules a bit; what happens in the
 447# edge cases?
 448#
 449# Note that there is a closely related case of a directory not being
 450# split on either side of history, but being renamed differently on
 451# each side.  See testcase 8e for that.
 452###########################################################################
 453
 454# Testcase 2a, Directory split into two on one side, with equal numbers of paths
 455#   Commit O: z/{b,c}
 456#   Commit A: y/b, w/c
 457#   Commit B: z/{b,c,d}
 458#   Expected: y/b, w/c, z/d, with warning about z/ -> (y/ vs. w/) conflict
 459test_expect_success '2a-setup: Directory split into two on one side, with equal numbers of paths' '
 460        test_create_repo 2a &&
 461        (
 462                cd 2a &&
 463
 464                mkdir z &&
 465                echo b >z/b &&
 466                echo c >z/c &&
 467                git add z &&
 468                test_tick &&
 469                git commit -m "O" &&
 470
 471                git branch O &&
 472                git branch A &&
 473                git branch B &&
 474
 475                git checkout A &&
 476                mkdir y &&
 477                mkdir w &&
 478                git mv z/b y/ &&
 479                git mv z/c w/ &&
 480                test_tick &&
 481                git commit -m "A" &&
 482
 483                git checkout B &&
 484                echo d >z/d &&
 485                git add z/d &&
 486                test_tick &&
 487                git commit -m "B"
 488        )
 489'
 490
 491test_expect_failure '2a-check: Directory split into two on one side, with equal numbers of paths' '
 492        (
 493                cd 2a &&
 494
 495                git checkout A^0 &&
 496
 497                test_must_fail git merge -s recursive B^0 >out &&
 498                test_i18ngrep "CONFLICT.*directory rename split" out &&
 499
 500                git ls-files -s >out &&
 501                test_line_count = 3 out &&
 502                git ls-files -u >out &&
 503                test_line_count = 0 out &&
 504                git ls-files -o >out &&
 505                test_line_count = 1 out &&
 506
 507                git rev-parse >actual \
 508                        :0:y/b :0:w/c :0:z/d &&
 509                git rev-parse >expect \
 510                         O:z/b  O:z/c  B:z/d &&
 511                test_cmp expect actual
 512        )
 513'
 514
 515# Testcase 2b, Directory split into two on one side, with equal numbers of paths
 516#   Commit O: z/{b,c}
 517#   Commit A: y/b, w/c
 518#   Commit B: z/{b,c}, x/d
 519#   Expected: y/b, w/c, x/d; No warning about z/ -> (y/ vs. w/) conflict
 520test_expect_success '2b-setup: Directory split into two on one side, with equal numbers of paths' '
 521        test_create_repo 2b &&
 522        (
 523                cd 2b &&
 524
 525                mkdir z &&
 526                echo b >z/b &&
 527                echo c >z/c &&
 528                git add z &&
 529                test_tick &&
 530                git commit -m "O" &&
 531
 532                git branch O &&
 533                git branch A &&
 534                git branch B &&
 535
 536                git checkout A &&
 537                mkdir y &&
 538                mkdir w &&
 539                git mv z/b y/ &&
 540                git mv z/c w/ &&
 541                test_tick &&
 542                git commit -m "A" &&
 543
 544                git checkout B &&
 545                mkdir x &&
 546                echo d >x/d &&
 547                git add x/d &&
 548                test_tick &&
 549                git commit -m "B"
 550        )
 551'
 552
 553test_expect_success '2b-check: Directory split into two on one side, with equal numbers of paths' '
 554        (
 555                cd 2b &&
 556
 557                git checkout A^0 &&
 558
 559                git merge -s recursive B^0 >out &&
 560
 561                git ls-files -s >out &&
 562                test_line_count = 3 out &&
 563                git ls-files -u >out &&
 564                test_line_count = 0 out &&
 565                git ls-files -o >out &&
 566                test_line_count = 1 out &&
 567
 568                git rev-parse >actual \
 569                        :0:y/b :0:w/c :0:x/d &&
 570                git rev-parse >expect \
 571                         O:z/b  O:z/c  B:x/d &&
 572                test_cmp expect actual &&
 573                test_i18ngrep ! "CONFLICT.*directory rename split" out
 574        )
 575'
 576
 577###########################################################################
 578# Rules suggested by section 2:
 579#
 580#   None; the rule was already covered in section 1.  These testcases are
 581#   here just to make sure the conflict resolution and necessary warning
 582#   messages are handled correctly.
 583###########################################################################
 584
 585
 586###########################################################################
 587# SECTION 3: Path in question is the source path for some rename already
 588#
 589# Combining cases from Section 1 and trying to handle them could lead to
 590# directory renaming detection being over-applied.  So, this section
 591# provides some good testcases to check that the implementation doesn't go
 592# too far.
 593###########################################################################
 594
 595# Testcase 3a, Avoid implicit rename if involved as source on other side
 596#   (Related to testcases 1c and 1f)
 597#   Commit O: z/{b,c,d}
 598#   Commit A: z/{b,c,d} (no change)
 599#   Commit B: y/{b,c}, x/d
 600#   Expected: y/{b,c}, x/d
 601test_expect_success '3a-setup: Avoid implicit rename if involved as source on other side' '
 602        test_create_repo 3a &&
 603        (
 604                cd 3a &&
 605
 606                mkdir z &&
 607                echo b >z/b &&
 608                echo c >z/c &&
 609                echo d >z/d &&
 610                git add z &&
 611                test_tick &&
 612                git commit -m "O" &&
 613
 614                git branch O &&
 615                git branch A &&
 616                git branch B &&
 617
 618                git checkout A &&
 619                test_tick &&
 620                git commit --allow-empty -m "A" &&
 621
 622                git checkout B &&
 623                mkdir y &&
 624                mkdir x &&
 625                git mv z/b y/ &&
 626                git mv z/c y/ &&
 627                git mv z/d x/ &&
 628                rmdir z &&
 629                test_tick &&
 630                git commit -m "B"
 631        )
 632'
 633
 634test_expect_success '3a-check: Avoid implicit rename if involved as source on other side' '
 635        (
 636                cd 3a &&
 637
 638                git checkout A^0 &&
 639
 640                git merge -s recursive B^0 &&
 641
 642                git ls-files -s >out &&
 643                test_line_count = 3 out &&
 644
 645                git rev-parse >actual \
 646                        HEAD:y/b HEAD:y/c HEAD:x/d &&
 647                git rev-parse >expect \
 648                        O:z/b    O:z/c    O:z/d &&
 649                test_cmp expect actual
 650        )
 651'
 652
 653# Testcase 3b, Avoid implicit rename if involved as source on other side
 654#   (Related to testcases 5c and 7c, also kind of 1e and 1f)
 655#   Commit O: z/{b,c,d}
 656#   Commit A: y/{b,c}, x/d
 657#   Commit B: z/{b,c}, w/d
 658#   Expected: y/{b,c}, CONFLICT:(z/d -> x/d vs. w/d)
 659#   NOTE: We're particularly checking that since z/d is already involved as
 660#         a source in a file rename on the same side of history, that we don't
 661#         get it involved in directory rename detection.  If it were, we might
 662#         end up with CONFLICT:(z/d -> y/d vs. x/d vs. w/d), i.e. a
 663#         rename/rename/rename(1to3) conflict, which is just weird.
 664test_expect_success '3b-setup: Avoid implicit rename if involved as source on current side' '
 665        test_create_repo 3b &&
 666        (
 667                cd 3b &&
 668
 669                mkdir z &&
 670                echo b >z/b &&
 671                echo c >z/c &&
 672                echo d >z/d &&
 673                git add z &&
 674                test_tick &&
 675                git commit -m "O" &&
 676
 677                git branch O &&
 678                git branch A &&
 679                git branch B &&
 680
 681                git checkout A &&
 682                mkdir y &&
 683                mkdir x &&
 684                git mv z/b y/ &&
 685                git mv z/c y/ &&
 686                git mv z/d x/ &&
 687                rmdir z &&
 688                test_tick &&
 689                git commit -m "A" &&
 690
 691                git checkout B &&
 692                mkdir w &&
 693                git mv z/d w/ &&
 694                test_tick &&
 695                git commit -m "B"
 696        )
 697'
 698
 699test_expect_success '3b-check: Avoid implicit rename if involved as source on current side' '
 700        (
 701                cd 3b &&
 702
 703                git checkout A^0 &&
 704
 705                test_must_fail git merge -s recursive B^0 >out &&
 706                test_i18ngrep CONFLICT.*rename/rename.*z/d.*x/d.*w/d out &&
 707                test_i18ngrep ! CONFLICT.*rename/rename.*y/d out &&
 708
 709                git ls-files -s >out &&
 710                test_line_count = 5 out &&
 711                git ls-files -u >out &&
 712                test_line_count = 3 out &&
 713                git ls-files -o >out &&
 714                test_line_count = 1 out &&
 715
 716                git rev-parse >actual \
 717                        :0:y/b :0:y/c :1:z/d :2:x/d :3:w/d &&
 718                git rev-parse >expect \
 719                         O:z/b  O:z/c  O:z/d  O:z/d  O:z/d &&
 720                test_cmp expect actual &&
 721
 722                test_path_is_missing z/d &&
 723                git hash-object >actual \
 724                        x/d   w/d &&
 725                git rev-parse >expect \
 726                        O:z/d O:z/d &&
 727                test_cmp expect actual
 728        )
 729'
 730
 731###########################################################################
 732# Rules suggested by section 3:
 733#
 734#   Avoid directory-rename-detection for a path, if that path is the source
 735#   of a rename on either side of a merge.
 736###########################################################################
 737
 738
 739###########################################################################
 740# SECTION 4: Partially renamed directory; still exists on both sides of merge
 741#
 742# What if we were to attempt to do directory rename detection when someone
 743# "mostly" moved a directory but still left some files around, or,
 744# equivalently, fully renamed a directory in one commmit and then recreated
 745# that directory in a later commit adding some new files and then tried to
 746# merge?
 747#
 748# It's hard to divine user intent in these cases, because you can make an
 749# argument that, depending on the intermediate history of the side being
 750# merged, that some users will want files in that directory to
 751# automatically be detected and renamed, while users with a different
 752# intermediate history wouldn't want that rename to happen.
 753#
 754# I think that it is best to simply not have directory rename detection
 755# apply to such cases.  My reasoning for this is four-fold: (1) it's
 756# easiest for users in general to figure out what happened if we don't
 757# apply directory rename detection in any such case, (2) it's an easy rule
 758# to explain ["We don't do directory rename detection if the directory
 759# still exists on both sides of the merge"], (3) we can get some hairy
 760# edge/corner cases that would be really confusing and possibly not even
 761# representable in the index if we were to even try, and [related to 3] (4)
 762# attempting to resolve this issue of divining user intent by examining
 763# intermediate history goes against the spirit of three-way merges and is a
 764# path towards crazy corner cases that are far more complex than what we're
 765# already dealing with.
 766#
 767# Note that the wording of the rule ("We don't do directory rename
 768# detection if the directory still exists on both sides of the merge.")
 769# also excludes "renaming" of a directory into a subdirectory of itself
 770# (e.g. /some/dir/* -> /some/dir/subdir/*).  It may be possible to carve
 771# out an exception for "renaming"-beneath-itself cases without opening
 772# weird edge/corner cases for other partial directory renames, but for now
 773# we are keeping the rule simple.
 774#
 775# This section contains a test for a partially-renamed-directory case.
 776###########################################################################
 777
 778# Testcase 4a, Directory split, with original directory still present
 779#   (Related to testcase 1f)
 780#   Commit O: z/{b,c,d,e}
 781#   Commit A: y/{b,c,d}, z/e
 782#   Commit B: z/{b,c,d,e,f}
 783#   Expected: y/{b,c,d}, z/{e,f}
 784#   NOTE: Even though most files from z moved to y, we don't want f to follow.
 785
 786test_expect_success '4a-setup: Directory split, with original directory still present' '
 787        test_create_repo 4a &&
 788        (
 789                cd 4a &&
 790
 791                mkdir z &&
 792                echo b >z/b &&
 793                echo c >z/c &&
 794                echo d >z/d &&
 795                echo e >z/e &&
 796                git add z &&
 797                test_tick &&
 798                git commit -m "O" &&
 799
 800                git branch O &&
 801                git branch A &&
 802                git branch B &&
 803
 804                git checkout A &&
 805                mkdir y &&
 806                git mv z/b y/ &&
 807                git mv z/c y/ &&
 808                git mv z/d y/ &&
 809                test_tick &&
 810                git commit -m "A" &&
 811
 812                git checkout B &&
 813                echo f >z/f &&
 814                git add z/f &&
 815                test_tick &&
 816                git commit -m "B"
 817        )
 818'
 819
 820test_expect_success '4a-check: Directory split, with original directory still present' '
 821        (
 822                cd 4a &&
 823
 824                git checkout A^0 &&
 825
 826                git merge -s recursive B^0 &&
 827
 828                git ls-files -s >out &&
 829                test_line_count = 5 out &&
 830                git ls-files -u >out &&
 831                test_line_count = 0 out &&
 832                git ls-files -o >out &&
 833                test_line_count = 1 out &&
 834
 835                git rev-parse >actual \
 836                        HEAD:y/b HEAD:y/c HEAD:y/d HEAD:z/e HEAD:z/f &&
 837                git rev-parse >expect \
 838                        O:z/b    O:z/c    O:z/d    O:z/e    B:z/f &&
 839                test_cmp expect actual
 840        )
 841'
 842
 843###########################################################################
 844# Rules suggested by section 4:
 845#
 846#   Directory-rename-detection should be turned off for any directories (as
 847#   a source for renames) that exist on both sides of the merge.  (The "as
 848#   a source for renames" clarification is due to cases like 1c where
 849#   the target directory exists on both sides and we do want the rename
 850#   detection.)  But, sadly, see testcase 8b.
 851###########################################################################
 852
 853
 854###########################################################################
 855# SECTION 5: Files/directories in the way of subset of to-be-renamed paths
 856#
 857# Implicitly renaming files due to a detected directory rename could run
 858# into problems if there are files or directories in the way of the paths
 859# we want to rename.  Explore such cases in this section.
 860###########################################################################
 861
 862# Testcase 5a, Merge directories, other side adds files to original and target
 863#   Commit O: z/{b,c},       y/d
 864#   Commit A: z/{b,c,e_1,f}, y/{d,e_2}
 865#   Commit B: y/{b,c,d}
 866#   Expected: z/e_1, y/{b,c,d,e_2,f} + CONFLICT warning
 867#   NOTE: While directory rename detection is active here causing z/f to
 868#         become y/f, we did not apply this for z/e_1 because that would
 869#         give us an add/add conflict for y/e_1 vs y/e_2.  This problem with
 870#         this add/add, is that both versions of y/e are from the same side
 871#         of history, giving us no way to represent this conflict in the
 872#         index.
 873
 874test_expect_success '5a-setup: Merge directories, other side adds files to original and target' '
 875        test_create_repo 5a &&
 876        (
 877                cd 5a &&
 878
 879                mkdir z &&
 880                echo b >z/b &&
 881                echo c >z/c &&
 882                mkdir y &&
 883                echo d >y/d &&
 884                git add z y &&
 885                test_tick &&
 886                git commit -m "O" &&
 887
 888                git branch O &&
 889                git branch A &&
 890                git branch B &&
 891
 892                git checkout A &&
 893                echo e1 >z/e &&
 894                echo f >z/f &&
 895                echo e2 >y/e &&
 896                git add z/e z/f y/e &&
 897                test_tick &&
 898                git commit -m "A" &&
 899
 900                git checkout B &&
 901                git mv z/b y/ &&
 902                git mv z/c y/ &&
 903                rmdir z &&
 904                test_tick &&
 905                git commit -m "B"
 906        )
 907'
 908
 909test_expect_failure '5a-check: Merge directories, other side adds files to original and target' '
 910        (
 911                cd 5a &&
 912
 913                git checkout A^0 &&
 914
 915                test_must_fail git merge -s recursive B^0 >out &&
 916                test_i18ngrep "CONFLICT.*implicit dir rename" out &&
 917
 918                git ls-files -s >out &&
 919                test_line_count = 6 out &&
 920                git ls-files -u >out &&
 921                test_line_count = 0 out &&
 922                git ls-files -o >out &&
 923                test_line_count = 1 out &&
 924
 925                git rev-parse >actual \
 926                        :0:y/b :0:y/c :0:y/d :0:y/e :0:z/e :0:y/f &&
 927                git rev-parse >expect \
 928                         O:z/b  O:z/c  O:y/d  A:y/e  A:z/e  A:z/f &&
 929                test_cmp expect actual
 930        )
 931'
 932
 933# Testcase 5b, Rename/delete in order to get add/add/add conflict
 934#   (Related to testcase 8d; these may appear slightly inconsistent to users;
 935#    Also related to testcases 7d and 7e)
 936#   Commit O: z/{b,c,d_1}
 937#   Commit A: y/{b,c,d_2}
 938#   Commit B: z/{b,c,d_1,e}, y/d_3
 939#   Expected: y/{b,c,e}, CONFLICT(add/add: y/d_2 vs. y/d_3)
 940#   NOTE: If z/d_1 in commit B were to be involved in dir rename detection, as
 941#         we normaly would since z/ is being renamed to y/, then this would be
 942#         a rename/delete (z/d_1 -> y/d_1 vs. deleted) AND an add/add/add
 943#         conflict of y/d_1 vs. y/d_2 vs. y/d_3.  Add/add/add is not
 944#         representable in the index, so the existence of y/d_3 needs to
 945#         cause us to bail on directory rename detection for that path, falling
 946#         back to git behavior without the directory rename detection.
 947
 948test_expect_success '5b-setup: Rename/delete in order to get add/add/add conflict' '
 949        test_create_repo 5b &&
 950        (
 951                cd 5b &&
 952
 953                mkdir z &&
 954                echo b >z/b &&
 955                echo c >z/c &&
 956                echo d1 >z/d &&
 957                git add z &&
 958                test_tick &&
 959                git commit -m "O" &&
 960
 961                git branch O &&
 962                git branch A &&
 963                git branch B &&
 964
 965                git checkout A &&
 966                git rm z/d &&
 967                git mv z y &&
 968                echo d2 >y/d &&
 969                git add y/d &&
 970                test_tick &&
 971                git commit -m "A" &&
 972
 973                git checkout B &&
 974                mkdir y &&
 975                echo d3 >y/d &&
 976                echo e >z/e &&
 977                git add y/d z/e &&
 978                test_tick &&
 979                git commit -m "B"
 980        )
 981'
 982
 983test_expect_failure '5b-check: Rename/delete in order to get add/add/add conflict' '
 984        (
 985                cd 5b &&
 986
 987                git checkout A^0 &&
 988
 989                test_must_fail git merge -s recursive B^0 >out &&
 990                test_i18ngrep "CONFLICT (add/add).* y/d" out &&
 991
 992                git ls-files -s >out &&
 993                test_line_count = 5 out &&
 994                git ls-files -u >out &&
 995                test_line_count = 2 out &&
 996                git ls-files -o >out &&
 997                test_line_count = 1 out &&
 998
 999                git rev-parse >actual \
1000                        :0:y/b :0:y/c :0:y/e :2:y/d :3:y/d &&
1001                git rev-parse >expect \
1002                         O:z/b  O:z/c  B:z/e  A:y/d  B:y/d &&
1003                test_cmp expect actual &&
1004
1005                test_must_fail git rev-parse :1:y/d &&
1006                test_path_is_file y/d
1007        )
1008'
1009
1010# Testcase 5c, Transitive rename would cause rename/rename/rename/add/add/add
1011#   (Directory rename detection would result in transitive rename vs.
1012#    rename/rename(1to2) and turn it into a rename/rename(1to3).  Further,
1013#    rename paths conflict with separate adds on the other side)
1014#   (Related to testcases 3b and 7c)
1015#   Commit O: z/{b,c}, x/d_1
1016#   Commit A: y/{b,c,d_2}, w/d_1
1017#   Commit B: z/{b,c,d_1,e}, w/d_3, y/d_4
1018#   Expected: A mess, but only a rename/rename(1to2)/add/add mess.  Use the
1019#             presence of y/d_4 in B to avoid doing transitive rename of
1020#             x/d_1 -> z/d_1 -> y/d_1, so that the only paths we have at
1021#             y/d are y/d_2 and y/d_4.  We still do the move from z/e to y/e,
1022#             though, because it doesn't have anything in the way.
1023
1024test_expect_success '5c-setup: Transitive rename would cause rename/rename/rename/add/add/add' '
1025        test_create_repo 5c &&
1026        (
1027                cd 5c &&
1028
1029                mkdir z &&
1030                echo b >z/b &&
1031                echo c >z/c &&
1032                mkdir x &&
1033                echo d1 >x/d &&
1034                git add z x &&
1035                test_tick &&
1036                git commit -m "O" &&
1037
1038                git branch O &&
1039                git branch A &&
1040                git branch B &&
1041
1042                git checkout A &&
1043                git mv z y &&
1044                echo d2 >y/d &&
1045                git add y/d &&
1046                git mv x w &&
1047                test_tick &&
1048                git commit -m "A" &&
1049
1050                git checkout B &&
1051                git mv x/d z/ &&
1052                mkdir w &&
1053                mkdir y &&
1054                echo d3 >w/d &&
1055                echo d4 >y/d &&
1056                echo e >z/e &&
1057                git add w/ y/ z/e &&
1058                test_tick &&
1059                git commit -m "B"
1060        )
1061'
1062
1063test_expect_failure '5c-check: Transitive rename would cause rename/rename/rename/add/add/add' '
1064        (
1065                cd 5c &&
1066
1067                git checkout A^0 &&
1068
1069                test_must_fail git merge -s recursive B^0 >out &&
1070                test_i18ngrep "CONFLICT (rename/rename).*x/d.*w/d.*z/d" out &&
1071                test_i18ngrep "CONFLICT (add/add).* y/d" out &&
1072
1073                git ls-files -s >out &&
1074                test_line_count = 9 out &&
1075                git ls-files -u >out &&
1076                test_line_count = 6 out &&
1077                git ls-files -o >out &&
1078                test_line_count = 3 out &&
1079
1080                git rev-parse >actual \
1081                        :0:y/b :0:y/c :0:y/e &&
1082                git rev-parse >expect \
1083                         O:z/b  O:z/c  B:z/e &&
1084                test_cmp expect actual &&
1085
1086                test_must_fail git rev-parse :1:y/d &&
1087                git rev-parse >actual \
1088                        :2:w/d :3:w/d :1:x/d :2:y/d :3:y/d :3:z/d &&
1089                git rev-parse >expect \
1090                         O:x/d  B:w/d  O:x/d  A:y/d  B:y/d  O:x/d &&
1091                test_cmp expect actual &&
1092
1093                git hash-object >actual \
1094                        w/d~HEAD w/d~B^0 z/d &&
1095                git rev-parse >expect \
1096                        O:x/d    B:w/d   O:x/d &&
1097                test_cmp expect actual &&
1098                test_path_is_missing x/d &&
1099                test_path_is_file y/d &&
1100                grep -q "<<<<" y/d  # conflict markers should be present
1101        )
1102'
1103
1104# Testcase 5d, Directory/file/file conflict due to directory rename
1105#   Commit O: z/{b,c}
1106#   Commit A: y/{b,c,d_1}
1107#   Commit B: z/{b,c,d_2,f}, y/d/e
1108#   Expected: y/{b,c,d/e,f}, z/d_2, CONFLICT(file/directory), y/d_1~HEAD
1109#   Note: The fact that y/d/ exists in B makes us bail on directory rename
1110#         detection for z/d_2, but that doesn't prevent us from applying the
1111#         directory rename detection for z/f -> y/f.
1112
1113test_expect_success '5d-setup: Directory/file/file conflict due to directory rename' '
1114        test_create_repo 5d &&
1115        (
1116                cd 5d &&
1117
1118                mkdir z &&
1119                echo b >z/b &&
1120                echo c >z/c &&
1121                git add z &&
1122                test_tick &&
1123                git commit -m "O" &&
1124
1125                git branch O &&
1126                git branch A &&
1127                git branch B &&
1128
1129                git checkout A &&
1130                git mv z y &&
1131                echo d1 >y/d &&
1132                git add y/d &&
1133                test_tick &&
1134                git commit -m "A" &&
1135
1136                git checkout B &&
1137                mkdir -p y/d &&
1138                echo e >y/d/e &&
1139                echo d2 >z/d &&
1140                echo f >z/f &&
1141                git add y/d/e z/d z/f &&
1142                test_tick &&
1143                git commit -m "B"
1144        )
1145'
1146
1147test_expect_failure '5d-check: Directory/file/file conflict due to directory rename' '
1148        (
1149                cd 5d &&
1150
1151                git checkout A^0 &&
1152
1153                test_must_fail git merge -s recursive B^0 >out &&
1154                test_i18ngrep "CONFLICT (file/directory).*y/d" out &&
1155
1156                git ls-files -s >out &&
1157                test_line_count = 6 out &&
1158                git ls-files -u >out &&
1159                test_line_count = 1 out &&
1160                git ls-files -o >out &&
1161                test_line_count = 2 out &&
1162
1163                git rev-parse >actual \
1164                        :0:y/b :0:y/c :0:z/d :0:y/f :2:y/d :0:y/d/e &&
1165                git rev-parse >expect \
1166                         O:z/b  O:z/c  B:z/d  B:z/f  A:y/d  B:y/d/e &&
1167                test_cmp expect actual &&
1168
1169                git hash-object y/d~HEAD >actual &&
1170                git rev-parse A:y/d >expect &&
1171                test_cmp expect actual
1172        )
1173'
1174
1175###########################################################################
1176# Rules suggested by section 5:
1177#
1178#   If a subset of to-be-renamed files have a file or directory in the way,
1179#   "turn off" the directory rename for those specific sub-paths, falling
1180#   back to old handling.  But, sadly, see testcases 8a and 8b.
1181###########################################################################
1182
1183
1184###########################################################################
1185# SECTION 6: Same side of the merge was the one that did the rename
1186#
1187# It may sound obvious that you only want to apply implicit directory
1188# renames to directories if the _other_ side of history did the renaming.
1189# If you did make an implementation that didn't explicitly enforce this
1190# rule, the majority of cases that would fall under this section would
1191# also be solved by following the rules from the above sections.  But
1192# there are still a few that stick out, so this section covers them just
1193# to make sure we also get them right.
1194###########################################################################
1195
1196# Testcase 6a, Tricky rename/delete
1197#   Commit O: z/{b,c,d}
1198#   Commit A: z/b
1199#   Commit B: y/{b,c}, z/d
1200#   Expected: y/b, CONFLICT(rename/delete, z/c -> y/c vs. NULL)
1201#   Note: We're just checking here that the rename of z/b and z/c to put
1202#         them under y/ doesn't accidentally catch z/d and make it look like
1203#         it is also involved in a rename/delete conflict.
1204
1205test_expect_success '6a-setup: Tricky rename/delete' '
1206        test_create_repo 6a &&
1207        (
1208                cd 6a &&
1209
1210                mkdir z &&
1211                echo b >z/b &&
1212                echo c >z/c &&
1213                echo d >z/d &&
1214                git add z &&
1215                test_tick &&
1216                git commit -m "O" &&
1217
1218                git branch O &&
1219                git branch A &&
1220                git branch B &&
1221
1222                git checkout A &&
1223                git rm z/c &&
1224                git rm z/d &&
1225                test_tick &&
1226                git commit -m "A" &&
1227
1228                git checkout B &&
1229                mkdir y &&
1230                git mv z/b y/ &&
1231                git mv z/c y/ &&
1232                test_tick &&
1233                git commit -m "B"
1234        )
1235'
1236
1237test_expect_success '6a-check: Tricky rename/delete' '
1238        (
1239                cd 6a &&
1240
1241                git checkout A^0 &&
1242
1243                test_must_fail git merge -s recursive B^0 >out &&
1244                test_i18ngrep "CONFLICT (rename/delete).*z/c.*y/c" out &&
1245
1246                git ls-files -s >out &&
1247                test_line_count = 2 out &&
1248                git ls-files -u >out &&
1249                test_line_count = 1 out &&
1250                git ls-files -o >out &&
1251                test_line_count = 1 out &&
1252
1253                git rev-parse >actual \
1254                        :0:y/b :3:y/c &&
1255                git rev-parse >expect \
1256                         O:z/b  O:z/c &&
1257                test_cmp expect actual
1258        )
1259'
1260
1261# Testcase 6b, Same rename done on both sides
1262#   (Related to testcases 6c and 8e)
1263#   Commit O: z/{b,c}
1264#   Commit A: y/{b,c}
1265#   Commit B: y/{b,c}, z/d
1266#   Expected: y/{b,c}, z/d
1267#   Note: If we did directory rename detection here, we'd move z/d into y/,
1268#         but B did that rename and still decided to put the file into z/,
1269#         so we probably shouldn't apply directory rename detection for it.
1270
1271test_expect_success '6b-setup: Same rename done on both sides' '
1272        test_create_repo 6b &&
1273        (
1274                cd 6b &&
1275
1276                mkdir z &&
1277                echo b >z/b &&
1278                echo c >z/c &&
1279                git add z &&
1280                test_tick &&
1281                git commit -m "O" &&
1282
1283                git branch O &&
1284                git branch A &&
1285                git branch B &&
1286
1287                git checkout A &&
1288                git mv z y &&
1289                test_tick &&
1290                git commit -m "A" &&
1291
1292                git checkout B &&
1293                git mv z y &&
1294                mkdir z &&
1295                echo d >z/d &&
1296                git add z/d &&
1297                test_tick &&
1298                git commit -m "B"
1299        )
1300'
1301
1302test_expect_success '6b-check: Same rename done on both sides' '
1303        (
1304                cd 6b &&
1305
1306                git checkout A^0 &&
1307
1308                git merge -s recursive B^0 &&
1309
1310                git ls-files -s >out &&
1311                test_line_count = 3 out &&
1312                git ls-files -u >out &&
1313                test_line_count = 0 out &&
1314                git ls-files -o >out &&
1315                test_line_count = 1 out &&
1316
1317                git rev-parse >actual \
1318                        HEAD:y/b HEAD:y/c HEAD:z/d &&
1319                git rev-parse >expect \
1320                        O:z/b    O:z/c    B:z/d &&
1321                test_cmp expect actual
1322        )
1323'
1324
1325# Testcase 6c, Rename only done on same side
1326#   (Related to testcases 6b and 8e)
1327#   Commit O: z/{b,c}
1328#   Commit A: z/{b,c} (no change)
1329#   Commit B: y/{b,c}, z/d
1330#   Expected: y/{b,c}, z/d
1331#   NOTE: Seems obvious, but just checking that the implementation doesn't
1332#         "accidentally detect a rename" and give us y/{b,c,d}.
1333
1334test_expect_success '6c-setup: Rename only done on same side' '
1335        test_create_repo 6c &&
1336        (
1337                cd 6c &&
1338
1339                mkdir z &&
1340                echo b >z/b &&
1341                echo c >z/c &&
1342                git add z &&
1343                test_tick &&
1344                git commit -m "O" &&
1345
1346                git branch O &&
1347                git branch A &&
1348                git branch B &&
1349
1350                git checkout A &&
1351                test_tick &&
1352                git commit --allow-empty -m "A" &&
1353
1354                git checkout B &&
1355                git mv z y &&
1356                mkdir z &&
1357                echo d >z/d &&
1358                git add z/d &&
1359                test_tick &&
1360                git commit -m "B"
1361        )
1362'
1363
1364test_expect_success '6c-check: Rename only done on same side' '
1365        (
1366                cd 6c &&
1367
1368                git checkout A^0 &&
1369
1370                git merge -s recursive B^0 &&
1371
1372                git ls-files -s >out &&
1373                test_line_count = 3 out &&
1374                git ls-files -u >out &&
1375                test_line_count = 0 out &&
1376                git ls-files -o >out &&
1377                test_line_count = 1 out &&
1378
1379                git rev-parse >actual \
1380                        HEAD:y/b HEAD:y/c HEAD:z/d &&
1381                git rev-parse >expect \
1382                        O:z/b    O:z/c    B:z/d &&
1383                test_cmp expect actual
1384        )
1385'
1386
1387# Testcase 6d, We don't always want transitive renaming
1388#   (Related to testcase 1c)
1389#   Commit O: z/{b,c}, x/d
1390#   Commit A: z/{b,c}, x/d (no change)
1391#   Commit B: y/{b,c}, z/d
1392#   Expected: y/{b,c}, z/d
1393#   NOTE: Again, this seems obvious but just checking that the implementation
1394#         doesn't "accidentally detect a rename" and give us y/{b,c,d}.
1395
1396test_expect_success '6d-setup: We do not always want transitive renaming' '
1397        test_create_repo 6d &&
1398        (
1399                cd 6d &&
1400
1401                mkdir z &&
1402                echo b >z/b &&
1403                echo c >z/c &&
1404                mkdir x &&
1405                echo d >x/d &&
1406                git add z x &&
1407                test_tick &&
1408                git commit -m "O" &&
1409
1410                git branch O &&
1411                git branch A &&
1412                git branch B &&
1413
1414                git checkout A &&
1415                test_tick &&
1416                git commit --allow-empty -m "A" &&
1417
1418                git checkout B &&
1419                git mv z y &&
1420                git mv x z &&
1421                test_tick &&
1422                git commit -m "B"
1423        )
1424'
1425
1426test_expect_success '6d-check: We do not always want transitive renaming' '
1427        (
1428                cd 6d &&
1429
1430                git checkout A^0 &&
1431
1432                git merge -s recursive B^0 &&
1433
1434                git ls-files -s >out &&
1435                test_line_count = 3 out &&
1436                git ls-files -u >out &&
1437                test_line_count = 0 out &&
1438                git ls-files -o >out &&
1439                test_line_count = 1 out &&
1440
1441                git rev-parse >actual \
1442                        HEAD:y/b HEAD:y/c HEAD:z/d &&
1443                git rev-parse >expect \
1444                        O:z/b    O:z/c    O:x/d &&
1445                test_cmp expect actual
1446        )
1447'
1448
1449# Testcase 6e, Add/add from one-side
1450#   Commit O: z/{b,c}
1451#   Commit A: z/{b,c} (no change)
1452#   Commit B: y/{b,c,d_1}, z/d_2
1453#   Expected: y/{b,c,d_1}, z/d_2
1454#   NOTE: Again, this seems obvious but just checking that the implementation
1455#         doesn't "accidentally detect a rename" and give us y/{b,c} +
1456#         add/add conflict on y/d_1 vs y/d_2.
1457
1458test_expect_success '6e-setup: Add/add from one side' '
1459        test_create_repo 6e &&
1460        (
1461                cd 6e &&
1462
1463                mkdir z &&
1464                echo b >z/b &&
1465                echo c >z/c &&
1466                git add z &&
1467                test_tick &&
1468                git commit -m "O" &&
1469
1470                git branch O &&
1471                git branch A &&
1472                git branch B &&
1473
1474                git checkout A &&
1475                test_tick &&
1476                git commit --allow-empty -m "A" &&
1477
1478                git checkout B &&
1479                git mv z y &&
1480                echo d1 > y/d &&
1481                mkdir z &&
1482                echo d2 > z/d &&
1483                git add y/d z/d &&
1484                test_tick &&
1485                git commit -m "B"
1486        )
1487'
1488
1489test_expect_success '6e-check: Add/add from one side' '
1490        (
1491                cd 6e &&
1492
1493                git checkout A^0 &&
1494
1495                git merge -s recursive B^0 &&
1496
1497                git ls-files -s >out &&
1498                test_line_count = 4 out &&
1499                git ls-files -u >out &&
1500                test_line_count = 0 out &&
1501                git ls-files -o >out &&
1502                test_line_count = 1 out &&
1503
1504                git rev-parse >actual \
1505                        HEAD:y/b HEAD:y/c HEAD:y/d HEAD:z/d &&
1506                git rev-parse >expect \
1507                        O:z/b    O:z/c    B:y/d    B:z/d &&
1508                test_cmp expect actual
1509        )
1510'
1511
1512###########################################################################
1513# Rules suggested by section 6:
1514#
1515#   Only apply implicit directory renames to directories if the other
1516#   side of history is the one doing the renaming.
1517###########################################################################
1518
1519
1520###########################################################################
1521# SECTION 7: More involved Edge/Corner cases
1522#
1523# The ruleset we have generated in the above sections seems to provide
1524# well-defined merges.  But can we find edge/corner cases that either (a)
1525# are harder for users to understand, or (b) have a resolution that is
1526# non-intuitive or suboptimal?
1527#
1528# The testcases in this section dive into cases that I've tried to craft in
1529# a way to find some that might be surprising to users or difficult for
1530# them to understand (the next section will look at non-intuitive or
1531# suboptimal merge results).  Some of the testcases are similar to ones
1532# from past sections, but have been simplified to try to highlight error
1533# messages using a "modified" path (due to the directory rename).  Are
1534# users okay with these?
1535#
1536# In my opinion, testcases that are difficult to understand from this
1537# section is due to difficulty in the testcase rather than the directory
1538# renaming (similar to how t6042 and t6036 have difficult resolutions due
1539# to the problem setup itself being complex).  And I don't think the
1540# error messages are a problem.
1541#
1542# On the other hand, the testcases in section 8 worry me slightly more...
1543###########################################################################
1544
1545# Testcase 7a, rename-dir vs. rename-dir (NOT split evenly) PLUS add-other-file
1546#   Commit O: z/{b,c}
1547#   Commit A: y/{b,c}
1548#   Commit B: w/b, x/c, z/d
1549#   Expected: y/d, CONFLICT(rename/rename for both z/b and z/c)
1550#   NOTE: There's a rename of z/ here, y/ has more renames, so z/d -> y/d.
1551
1552test_expect_success '7a-setup: rename-dir vs. rename-dir (NOT split evenly) PLUS add-other-file' '
1553        test_create_repo 7a &&
1554        (
1555                cd 7a &&
1556
1557                mkdir z &&
1558                echo b >z/b &&
1559                echo c >z/c &&
1560                git add z &&
1561                test_tick &&
1562                git commit -m "O" &&
1563
1564                git branch O &&
1565                git branch A &&
1566                git branch B &&
1567
1568                git checkout A &&
1569                git mv z y &&
1570                test_tick &&
1571                git commit -m "A" &&
1572
1573                git checkout B &&
1574                mkdir w &&
1575                mkdir x &&
1576                git mv z/b w/ &&
1577                git mv z/c x/ &&
1578                echo d > z/d &&
1579                git add z/d &&
1580                test_tick &&
1581                git commit -m "B"
1582        )
1583'
1584
1585test_expect_failure '7a-check: rename-dir vs. rename-dir (NOT split evenly) PLUS add-other-file' '
1586        (
1587                cd 7a &&
1588
1589                git checkout A^0 &&
1590
1591                test_must_fail git merge -s recursive B^0 >out &&
1592                test_i18ngrep "CONFLICT (rename/rename).*z/b.*y/b.*w/b" out &&
1593                test_i18ngrep "CONFLICT (rename/rename).*z/c.*y/c.*x/c" out &&
1594
1595                git ls-files -s >out &&
1596                test_line_count = 7 out &&
1597                git ls-files -u >out &&
1598                test_line_count = 6 out &&
1599                git ls-files -o >out &&
1600                test_line_count = 1 out &&
1601
1602                git rev-parse >actual \
1603                        :1:z/b :2:y/b :3:w/b :1:z/c :2:y/c :3:x/c :0:y/d &&
1604                git rev-parse >expect \
1605                         O:z/b  O:z/b  O:z/b  O:z/c  O:z/c  O:z/c  B:z/d &&
1606                test_cmp expect actual &&
1607
1608                git hash-object >actual \
1609                        y/b   w/b   y/c   x/c &&
1610                git rev-parse >expect \
1611                        O:z/b O:z/b O:z/c O:z/c &&
1612                test_cmp expect actual
1613        )
1614'
1615
1616# Testcase 7b, rename/rename(2to1), but only due to transitive rename
1617#   (Related to testcase 1d)
1618#   Commit O: z/{b,c},     x/d_1, w/d_2
1619#   Commit A: y/{b,c,d_2}, x/d_1
1620#   Commit B: z/{b,c,d_1},        w/d_2
1621#   Expected: y/{b,c}, CONFLICT(rename/rename(2to1): x/d_1, w/d_2 -> y_d)
1622
1623test_expect_success '7b-setup: rename/rename(2to1), but only due to transitive rename' '
1624        test_create_repo 7b &&
1625        (
1626                cd 7b &&
1627
1628                mkdir z &&
1629                mkdir x &&
1630                mkdir w &&
1631                echo b >z/b &&
1632                echo c >z/c &&
1633                echo d1 > x/d &&
1634                echo d2 > w/d &&
1635                git add z x w &&
1636                test_tick &&
1637                git commit -m "O" &&
1638
1639                git branch O &&
1640                git branch A &&
1641                git branch B &&
1642
1643                git checkout A &&
1644                git mv z y &&
1645                git mv w/d y/ &&
1646                test_tick &&
1647                git commit -m "A" &&
1648
1649                git checkout B &&
1650                git mv x/d z/ &&
1651                rmdir x &&
1652                test_tick &&
1653                git commit -m "B"
1654        )
1655'
1656
1657test_expect_failure '7b-check: rename/rename(2to1), but only due to transitive rename' '
1658        (
1659                cd 7b &&
1660
1661                git checkout A^0 &&
1662
1663                test_must_fail git merge -s recursive B^0 >out &&
1664                test_i18ngrep "CONFLICT (rename/rename)" out &&
1665
1666                git ls-files -s >out &&
1667                test_line_count = 4 out &&
1668                git ls-files -u >out &&
1669                test_line_count = 2 out &&
1670                git ls-files -o >out &&
1671                test_line_count = 3 out &&
1672
1673                git rev-parse >actual \
1674                        :0:y/b :0:y/c :2:y/d :3:y/d &&
1675                git rev-parse >expect \
1676                         O:z/b  O:z/c  O:w/d  O:x/d &&
1677                test_cmp expect actual &&
1678
1679                test_path_is_missing y/d &&
1680                test_path_is_file y/d~HEAD &&
1681                test_path_is_file y/d~B^0 &&
1682
1683                git hash-object >actual \
1684                        y/d~HEAD y/d~B^0 &&
1685                git rev-parse >expect \
1686                        O:w/d    O:x/d &&
1687                test_cmp expect actual
1688        )
1689'
1690
1691# Testcase 7c, rename/rename(1to...2or3); transitive rename may add complexity
1692#   (Related to testcases 3b and 5c)
1693#   Commit O: z/{b,c}, x/d
1694#   Commit A: y/{b,c}, w/d
1695#   Commit B: z/{b,c,d}
1696#   Expected: y/{b,c}, CONFLICT(x/d -> w/d vs. y/d)
1697#   NOTE: z/ was renamed to y/ so we do want to report
1698#         neither CONFLICT(x/d -> w/d vs. z/d)
1699#         nor CONFLiCT x/d -> w/d vs. y/d vs. z/d)
1700
1701test_expect_success '7c-setup: rename/rename(1to...2or3); transitive rename may add complexity' '
1702        test_create_repo 7c &&
1703        (
1704                cd 7c &&
1705
1706                mkdir z &&
1707                echo b >z/b &&
1708                echo c >z/c &&
1709                mkdir x &&
1710                echo d >x/d &&
1711                git add z x &&
1712                test_tick &&
1713                git commit -m "O" &&
1714
1715                git branch O &&
1716                git branch A &&
1717                git branch B &&
1718
1719                git checkout A &&
1720                git mv z y &&
1721                git mv x w &&
1722                test_tick &&
1723                git commit -m "A" &&
1724
1725                git checkout B &&
1726                git mv x/d z/ &&
1727                rmdir x &&
1728                test_tick &&
1729                git commit -m "B"
1730        )
1731'
1732
1733test_expect_failure '7c-check: rename/rename(1to...2or3); transitive rename may add complexity' '
1734        (
1735                cd 7c &&
1736
1737                git checkout A^0 &&
1738
1739                test_must_fail git merge -s recursive B^0 >out &&
1740                test_i18ngrep "CONFLICT (rename/rename).*x/d.*w/d.*y/d" out &&
1741
1742                git ls-files -s >out &&
1743                test_line_count = 5 out &&
1744                git ls-files -u >out &&
1745                test_line_count = 3 out &&
1746                git ls-files -o >out &&
1747                test_line_count = 1 out &&
1748
1749                git rev-parse >actual \
1750                        :0:y/b :0:y/c :1:x/d :2:w/d :3:y/d &&
1751                git rev-parse >expect \
1752                         O:z/b  O:z/c  O:x/d  O:x/d  O:x/d &&
1753                test_cmp expect actual
1754        )
1755'
1756
1757# Testcase 7d, transitive rename involved in rename/delete; how is it reported?
1758#   (Related somewhat to testcases 5b and 8d)
1759#   Commit O: z/{b,c}, x/d
1760#   Commit A: y/{b,c}
1761#   Commit B: z/{b,c,d}
1762#   Expected: y/{b,c}, CONFLICT(delete x/d vs rename to y/d)
1763#   NOTE: z->y so NOT CONFLICT(delete x/d vs rename to z/d)
1764
1765test_expect_success '7d-setup: transitive rename involved in rename/delete; how is it reported?' '
1766        test_create_repo 7d &&
1767        (
1768                cd 7d &&
1769
1770                mkdir z &&
1771                echo b >z/b &&
1772                echo c >z/c &&
1773                mkdir x &&
1774                echo d >x/d &&
1775                git add z x &&
1776                test_tick &&
1777                git commit -m "O" &&
1778
1779                git branch O &&
1780                git branch A &&
1781                git branch B &&
1782
1783                git checkout A &&
1784                git mv z y &&
1785                git rm -rf x &&
1786                test_tick &&
1787                git commit -m "A" &&
1788
1789                git checkout B &&
1790                git mv x/d z/ &&
1791                rmdir x &&
1792                test_tick &&
1793                git commit -m "B"
1794        )
1795'
1796
1797test_expect_failure '7d-check: transitive rename involved in rename/delete; how is it reported?' '
1798        (
1799                cd 7d &&
1800
1801                git checkout A^0 &&
1802
1803                test_must_fail git merge -s recursive B^0 >out &&
1804                test_i18ngrep "CONFLICT (rename/delete).*x/d.*y/d" out &&
1805
1806                git ls-files -s >out &&
1807                test_line_count = 3 out &&
1808                git ls-files -u >out &&
1809                test_line_count = 1 out &&
1810                git ls-files -o >out &&
1811                test_line_count = 1 out &&
1812
1813                git rev-parse >actual \
1814                        :0:y/b :0:y/c :3:y/d &&
1815                git rev-parse >expect \
1816                         O:z/b  O:z/c  O:x/d &&
1817                test_cmp expect actual
1818        )
1819'
1820
1821# Testcase 7e, transitive rename in rename/delete AND dirs in the way
1822#   (Very similar to 'both rename source and destination involved in D/F conflict' from t6022-merge-rename.sh)
1823#   (Also related to testcases 9c and 9d)
1824#   Commit O: z/{b,c},     x/d_1
1825#   Commit A: y/{b,c,d/g}, x/d/f
1826#   Commit B: z/{b,c,d_1}
1827#   Expected: rename/delete(x/d_1->y/d_1 vs. None) + D/F conflict on y/d
1828#             y/{b,c,d/g}, y/d_1~B^0, x/d/f
1829
1830#   NOTE: The main path of interest here is d_1 and where it ends up, but
1831#         this is actually a case that has two potential directory renames
1832#         involved and D/F conflict(s), so it makes sense to walk through
1833#         each step.
1834#
1835#         Commit A renames z/ -> y/.  Thus everything that B adds to z/
1836#         should be instead moved to y/.  This gives us the D/F conflict on
1837#         y/d because x/d_1 -> z/d_1 -> y/d_1 conflicts with y/d/g.
1838#
1839#         Further, commit B renames x/ -> z/, thus everything A adds to x/
1840#         should instead be moved to z/...BUT we removed z/ and renamed it
1841#         to y/, so maybe everything should move not from x/ to z/, but
1842#         from x/ to z/ to y/.  Doing so might make sense from the logic so
1843#         far, but note that commit A had both an x/ and a y/; it did the
1844#         renaming of z/ to y/ and created x/d/f and it clearly made these
1845#         things separate, so it doesn't make much sense to push these
1846#         together.  Doing so is what I'd call a doubly transitive rename;
1847#         see testcases 9c and 9d for further discussion of this issue and
1848#         how it's resolved.
1849
1850test_expect_success '7e-setup: transitive rename in rename/delete AND dirs in the way' '
1851        test_create_repo 7e &&
1852        (
1853                cd 7e &&
1854
1855                mkdir z &&
1856                echo b >z/b &&
1857                echo c >z/c &&
1858                mkdir x &&
1859                echo d1 >x/d &&
1860                git add z x &&
1861                test_tick &&
1862                git commit -m "O" &&
1863
1864                git branch O &&
1865                git branch A &&
1866                git branch B &&
1867
1868                git checkout A &&
1869                git mv z y &&
1870                git rm x/d &&
1871                mkdir -p x/d &&
1872                mkdir -p y/d &&
1873                echo f >x/d/f &&
1874                echo g >y/d/g &&
1875                git add x/d/f y/d/g &&
1876                test_tick &&
1877                git commit -m "A" &&
1878
1879                git checkout B &&
1880                git mv x/d z/ &&
1881                rmdir x &&
1882                test_tick &&
1883                git commit -m "B"
1884        )
1885'
1886
1887test_expect_failure '7e-check: transitive rename in rename/delete AND dirs in the way' '
1888        (
1889                cd 7e &&
1890
1891                git checkout A^0 &&
1892
1893                test_must_fail git merge -s recursive B^0 >out &&
1894                test_i18ngrep "CONFLICT (rename/delete).*x/d.*y/d" out &&
1895
1896                git ls-files -s >out &&
1897                test_line_count = 5 out &&
1898                git ls-files -u >out &&
1899                test_line_count = 1 out &&
1900                git ls-files -o >out &&
1901                test_line_count = 2 out &&
1902
1903                git rev-parse >actual \
1904                        :0:x/d/f :0:y/d/g :0:y/b :0:y/c :3:y/d &&
1905                git rev-parse >expect \
1906                         A:x/d/f  A:y/d/g  O:z/b  O:z/c  O:x/d &&
1907                test_cmp expect actual &&
1908
1909                git hash-object y/d~B^0 >actual &&
1910                git rev-parse O:x/d >expect &&
1911                test_cmp expect actual
1912        )
1913'
1914
1915test_done