t/t6426-merge-skip-unneeded-updates.sh

   1 #!/bin/sh
   2
   3 test_description="merge cases"
   4
   5 # The setup for all of them, pictorially, is:
   6 #
   7 #      A
   8 #      o
   9 #     / \
  10 #  O o   ?
  11 #     \ /
  12 #      o
  13 #      B
  14 #
  15 # To help make it easier to follow the flow of tests, they have been
  16 # divided into sections and each test will start with a quick explanation
  17 # of what commits O, A, and B contain.
  18 #
  19 # Notation:
  20 #    z/{b,c}   means  files z/b and z/c both exist
  21 #    x/d_1     means  file x/d exists with content d1.  (Purpose of the
  22 #                     underscore notation is to differentiate different
  23 #                     files that might be renamed into each other's paths.)
  24
  25 . ./test-lib.sh
  26 . "$TEST_DIRECTORY"/lib-merge.sh
  27
  28
  29 ###########################################################################
  30 # SECTION 1: Cases involving no renames (one side has subset of changes of
  31 #            the other side)
  32 ###########################################################################
  33
  34 # Testcase 1a, Changes on A, subset of changes on B
  35 #   Commit O: b_1
  36 #   Commit A: b_2
  37 #   Commit B: b_3
  38 #   Expected: b_2
  39
  40 test_setup_1a () {
  41         test_create_repo 1a_$1 &&
  42         (
  43                 cd 1a_$1 &&
  44
  45                 test_write_lines 1 2 3 4 5 6 7 8 9 10 >b &&
  46                 git add b &&
  47                 test_tick &&
  48                 git commit -m "O" &&
  49
  50                 git branch O &&
  51                 git branch A &&
  52                 git branch B &&
  53
  54                 git checkout A &&
  55                 test_write_lines 1 2 3 4 5 5.5 6 7 8 9 10 10.5 >b &&
  56                 git add b &&
  57                 test_tick &&
  58                 git commit -m "A" &&
  59
  60                 git checkout B &&
  61                 test_write_lines 1 2 3 4 5 5.5 6 7 8 9 10 >b &&
  62                 git add b &&
  63                 test_tick &&
  64                 git commit -m "B"
  65         )
  66 }
  67
  68 test_expect_success '1a-L: Modify(A)/Modify(B), change on B subset of A' '
  69         test_setup_1a L &&
  70         (
  71                 cd 1a_L &&
  72
  73                 git checkout A^0 &&
  74
  75                 test-tool chmtime --get -3600 b >old-mtime &&
  76
  77                 GIT_MERGE_VERBOSITY=3 git merge -s recursive B^0 >out 2>err &&
  78
  79                 test_must_be_empty err &&
  80
  81                 # Make sure b was NOT updated
  82                 test-tool chmtime --get b >new-mtime &&
  83                 test_cmp old-mtime new-mtime &&
  84
  85                 git ls-files -s >index_files &&
  86                 test_line_count = 1 index_files &&
  87
  88                 git rev-parse >actual HEAD:b &&
  89                 git rev-parse >expect A:b &&
  90                 test_cmp expect actual &&
  91
  92                 git hash-object b   >actual &&
  93                 git rev-parse   A:b >expect &&
  94                 test_cmp expect actual
  95         )
  96 '
  97
  98 test_expect_success '1a-R: Modify(A)/Modify(B), change on B subset of A' '
  99         test_setup_1a R &&
 100         (
 101                 cd 1a_R &&
 102
 103                 git checkout B^0 &&
 104
 105                 test-tool chmtime --get -3600 b >old-mtime &&
 106                 GIT_MERGE_VERBOSITY=3 git merge -s recursive A^0 >out 2>err &&
 107
 108                 # Make sure b WAS updated
 109                 test-tool chmtime --get b >new-mtime &&
 110                 test $(cat old-mtime) -lt $(cat new-mtime) &&
 111
 112                 test_must_be_empty err &&
 113
 114                 git ls-files -s >index_files &&
 115                 test_line_count = 1 index_files &&
 116
 117                 git rev-parse >actual HEAD:b &&
 118                 git rev-parse >expect A:b &&
 119                 test_cmp expect actual &&
 120
 121                 git hash-object b   >actual &&
 122                 git rev-parse   A:b >expect &&
 123                 test_cmp expect actual
 124         )
 125 '
 126
 127
 128 ###########################################################################
 129 # SECTION 2: Cases involving basic renames
 130 ###########################################################################
 131
 132 # Testcase 2a, Changes on A, rename on B
 133 #   Commit O: b_1
 134 #   Commit A: b_2
 135 #   Commit B: c_1
 136 #   Expected: c_2
 137
 138 test_setup_2a () {
 139         test_create_repo 2a_$1 &&
 140         (
 141                 cd 2a_$1 &&
 142
 143                 test_seq 1 10 >b &&
 144                 git add b &&
 145                 test_tick &&
 146                 git commit -m "O" &&
 147
 148                 git branch O &&
 149                 git branch A &&
 150                 git branch B &&
 151
 152                 git checkout A &&
 153                 test_seq 1 11 >b &&
 154                 git add b &&
 155                 test_tick &&
 156                 git commit -m "A" &&
 157
 158                 git checkout B &&
 159                 git mv b c &&
 160                 test_tick &&
 161                 git commit -m "B"
 162         )
 163 }
 164
 165 test_expect_success '2a-L: Modify/rename, merge into modify side' '
 166         test_setup_2a L &&
 167         (
 168                 cd 2a_L &&
 169
 170                 git checkout A^0 &&
 171
 172                 test_path_is_missing c &&
 173                 GIT_MERGE_VERBOSITY=3 git merge -s recursive B^0 >out 2>err &&
 174
 175                 test_path_is_file c &&
 176
 177                 git ls-files -s >index_files &&
 178                 test_line_count = 1 index_files &&
 179
 180                 git rev-parse >actual HEAD:c &&
 181                 git rev-parse >expect A:b &&
 182                 test_cmp expect actual &&
 183
 184                 git hash-object c   >actual &&
 185                 git rev-parse   A:b >expect &&
 186                 test_cmp expect actual &&
 187
 188                 test_must_fail git rev-parse HEAD:b &&
 189                 test_path_is_missing b
 190         )
 191 '
 192
 193 test_expect_success '2a-R: Modify/rename, merge into rename side' '
 194         test_setup_2a R &&
 195         (
 196                 cd 2a_R &&
 197
 198                 git checkout B^0 &&
 199
 200                 test-tool chmtime --get -3600 c >old-mtime &&
 201                 GIT_MERGE_VERBOSITY=3 git merge -s recursive A^0 >out 2>err &&
 202
 203                 # Make sure c WAS updated
 204                 test-tool chmtime --get c >new-mtime &&
 205                 test $(cat old-mtime) -lt $(cat new-mtime) &&
 206
 207                 test_must_be_empty err &&
 208
 209                 git ls-files -s >index_files &&
 210                 test_line_count = 1 index_files &&
 211
 212                 git rev-parse >actual HEAD:c &&
 213                 git rev-parse >expect A:b &&
 214                 test_cmp expect actual &&
 215
 216                 git hash-object c   >actual &&
 217                 git rev-parse   A:b >expect &&
 218                 test_cmp expect actual &&
 219
 220                 test_must_fail git rev-parse HEAD:b &&
 221                 test_path_is_missing b
 222         )
 223 '
 224
 225 # Testcase 2b, Changed and renamed on A, subset of changes on B
 226 #   Commit O: b_1
 227 #   Commit A: c_2
 228 #   Commit B: b_3
 229 #   Expected: c_2
 230
 231 test_setup_2b () {
 232         test_create_repo 2b_$1 &&
 233         (
 234                 cd 2b_$1 &&
 235
 236                 test_write_lines 1 2 3 4 5 6 7 8 9 10 >b &&
 237                 git add b &&
 238                 test_tick &&
 239                 git commit -m "O" &&
 240
 241                 git branch O &&
 242                 git branch A &&
 243                 git branch B &&
 244
 245                 git checkout A &&
 246                 test_write_lines 1 2 3 4 5 5.5 6 7 8 9 10 10.5 >b &&
 247                 git add b &&
 248                 git mv b c &&
 249                 test_tick &&
 250                 git commit -m "A" &&
 251
 252                 git checkout B &&
 253                 test_write_lines 1 2 3 4 5 5.5 6 7 8 9 10 >b &&
 254                 git add b &&
 255                 test_tick &&
 256                 git commit -m "B"
 257         )
 258 }
 259
 260 test_expect_success '2b-L: Rename+Mod(A)/Mod(B), B mods subset of A' '
 261         test_setup_2b L &&
 262         (
 263                 cd 2b_L &&
 264
 265                 git checkout A^0 &&
 266
 267                 test-tool chmtime --get -3600 c >old-mtime &&
 268                 GIT_MERGE_VERBOSITY=3 git merge -s recursive B^0 >out 2>err &&
 269
 270                 test_must_be_empty err &&
 271
 272                 # Make sure c WAS updated
 273                 test-tool chmtime --get c >new-mtime &&
 274                 test_cmp old-mtime new-mtime &&
 275
 276                 git ls-files -s >index_files &&
 277                 test_line_count = 1 index_files &&
 278
 279                 git rev-parse >actual HEAD:c &&
 280                 git rev-parse >expect A:c &&
 281                 test_cmp expect actual &&
 282
 283                 git hash-object c   >actual &&
 284                 git rev-parse   A:c >expect &&
 285                 test_cmp expect actual &&
 286
 287                 test_must_fail git rev-parse HEAD:b &&
 288                 test_path_is_missing b
 289         )
 290 '
 291
 292 test_expect_success '2b-R: Rename+Mod(A)/Mod(B), B mods subset of A' '
 293         test_setup_2b R &&
 294         (
 295                 cd 2b_R &&
 296
 297                 git checkout B^0 &&
 298
 299                 test_path_is_missing c &&
 300                 GIT_MERGE_VERBOSITY=3 git merge -s recursive A^0 >out 2>err &&
 301
 302                 # Make sure c now present (and thus was updated)
 303                 test_path_is_file c &&
 304
 305                 test_must_be_empty err &&
 306
 307                 git ls-files -s >index_files &&
 308                 test_line_count = 1 index_files &&
 309
 310                 git rev-parse >actual HEAD:c &&
 311                 git rev-parse >expect A:c &&
 312                 test_cmp expect actual &&
 313
 314                 git hash-object c   >actual &&
 315                 git rev-parse   A:c >expect &&
 316                 test_cmp expect actual &&
 317
 318                 test_must_fail git rev-parse HEAD:b &&
 319                 test_path_is_missing b
 320         )
 321 '
 322
 323 # Testcase 2c, Changes on A, rename on B
 324 #   Commit O: b_1
 325 #   Commit A: b_2, c_3
 326 #   Commit B: c_1
 327 #   Expected: rename/add conflict c_2 vs c_3
 328 #
 329 #   NOTE: Since A modified b_1->b_2, and B renamed b_1->c_1, the threeway
 330 #         merge of those files should result in c_2.  We then should have a
 331 #         rename/add conflict between c_2 and c_3.  However, if we note in
 332 #         merge_content() that A had the right contents (b_2 has same
 333 #         contents as c_2, just at a different name), and that A had the
 334 #         right path present (c_3 existed) and thus decides that it can
 335 #         skip the update, then we're in trouble.  This test verifies we do
 336 #         not make that particular mistake.
 337
 338 test_setup_2c () {
 339         test_create_repo 2c &&
 340         (
 341                 cd 2c &&
 342
 343                 test_seq 1 10 >b &&
 344                 git add b &&
 345                 test_tick &&
 346                 git commit -m "O" &&
 347
 348                 git branch O &&
 349                 git branch A &&
 350                 git branch B &&
 351
 352                 git checkout A &&
 353                 test_seq 1 11 >b &&
 354                 echo whatever >c &&
 355                 git add b c &&
 356                 test_tick &&
 357                 git commit -m "A" &&
 358
 359                 git checkout B &&
 360                 git mv b c &&
 361                 test_tick &&
 362                 git commit -m "B"
 363         )
 364 }
 365
 366 test_expect_success '2c: Modify b & add c VS rename b->c' '
 367         test_setup_2c &&
 368         (
 369                 cd 2c &&
 370
 371                 git checkout A^0 &&
 372
 373                 test-tool chmtime --get -3600 c >old-mtime &&
 374                 GIT_MERGE_VERBOSITY=3 &&
 375                 export GIT_MERGE_VERBOSITY &&
 376                 test_must_fail git merge -s recursive B^0 >out 2>err &&
 377
 378                 test_i18ngrep "CONFLICT (.*/add):" out &&
 379                 test_must_be_empty err &&
 380
 381                 # Make sure c WAS updated
 382                 test-tool chmtime --get c >new-mtime &&
 383                 test $(cat old-mtime) -lt $(cat new-mtime)
 384
 385                 # FIXME: rename/add conflicts are horribly broken right now;
 386                 # when I get back to my patch series fixing it and
 387                 # rename/rename(2to1) conflicts to bring them in line with
 388                 # how add/add conflicts behave, then checks like the below
 389                 # could be added.  But that patch series is waiting until
 390                 # the rename-directory-detection series lands, which this
 391                 # is part of.  And in the mean time, I do not want to further
 392                 # enforce broken behavior.  So for now, the main test is the
 393                 # one above that err is an empty file.
 394
 395                 #git ls-files -s >index_files &&
 396                 #test_line_count = 2 index_files &&
 397
 398                 #git rev-parse >actual :2:c :3:c &&
 399                 #git rev-parse >expect A:b  A:c  &&
 400                 #test_cmp expect actual &&
 401
 402                 #git cat-file -p A:b >>merged &&
 403                 #git cat-file -p A:c >>merge-me &&
 404                 #>empty &&
 405                 #test_must_fail git merge-file \
 406                 #       -L "Temporary merge branch 1" \
 407                 #       -L "" \
 408                 #       -L "Temporary merge branch 2" \
 409                 #       merged empty merge-me &&
 410                 #sed -e "s/^\([<=>]\)/\1\1\1/" merged >merged-internal &&
 411
 412                 #git hash-object c               >actual &&
 413                 #git hash-object merged-internal >expect &&
 414                 #test_cmp expect actual &&
 415
 416                 #test_path_is_missing b
 417         )
 418 '
 419
 420
 421 ###########################################################################
 422 # SECTION 3: Cases involving directory renames
 423 #
 424 # NOTE:
 425 #   Directory renames only apply when one side renames a directory, and the
 426 #   other side adds or renames a path into that directory.  Applying the
 427 #   directory rename to that new path creates a new pathname that didn't
 428 #   exist on either side of history.  Thus, it is impossible for the
 429 #   merge contents to already be at the right path, so all of these checks
 430 #   exist just to make sure that updates are not skipped.
 431 ###########################################################################
 432
 433 # Testcase 3a, Change + rename into dir foo on A, dir rename foo->bar on B
 434 #   Commit O: bq_1, foo/whatever
 435 #   Commit A: foo/{bq_2, whatever}
 436 #   Commit B: bq_1, bar/whatever
 437 #   Expected: bar/{bq_2, whatever}
 438
 439 test_setup_3a () {
 440         test_create_repo 3a_$1 &&
 441         (
 442                 cd 3a_$1 &&
 443
 444                 mkdir foo &&
 445                 test_seq 1 10 >bq &&
 446                 test_write_lines a b c d e f g h i j k >foo/whatever &&
 447                 git add bq foo/whatever &&
 448                 test_tick &&
 449                 git commit -m "O" &&
 450
 451                 git branch O &&
 452                 git branch A &&
 453                 git branch B &&
 454
 455                 git checkout A &&
 456                 test_seq 1 11 >bq &&
 457                 git add bq &&
 458                 git mv bq foo/ &&
 459                 test_tick &&
 460                 git commit -m "A" &&
 461
 462                 git checkout B &&
 463                 git mv foo/ bar/ &&
 464                 test_tick &&
 465                 git commit -m "B"
 466         )
 467 }
 468
 469 test_expect_success '3a-L: bq_1->foo/bq_2 on A, foo/->bar/ on B' '
 470         test_setup_3a L &&
 471         (
 472                 cd 3a_L &&
 473
 474                 git checkout A^0 &&
 475
 476                 test_path_is_missing bar/bq &&
 477                 GIT_MERGE_VERBOSITY=3 git -c merge.directoryRenames=true merge -s recursive B^0 >out 2>err &&
 478
 479                 test_must_be_empty err &&
 480
 481                 test_path_is_file bar/bq &&
 482
 483                 git ls-files -s >index_files &&
 484                 test_line_count = 2 index_files &&
 485
 486                 git rev-parse >actual HEAD:bar/bq HEAD:bar/whatever &&
 487                 git rev-parse >expect A:foo/bq    A:foo/whatever &&
 488                 test_cmp expect actual &&
 489
 490                 git hash-object bar/bq   bar/whatever   >actual &&
 491                 git rev-parse   A:foo/bq A:foo/whatever >expect &&
 492                 test_cmp expect actual &&
 493
 494                 test_must_fail git rev-parse HEAD:bq HEAD:foo/bq &&
 495                 test_path_is_missing bq &&
 496                 test_path_is_missing foo/bq &&
 497                 test_path_is_missing foo/whatever
 498         )
 499 '
 500
 501 test_expect_success '3a-R: bq_1->foo/bq_2 on A, foo/->bar/ on B' '
 502         test_setup_3a R &&
 503         (
 504                 cd 3a_R &&
 505
 506                 git checkout B^0 &&
 507
 508                 test_path_is_missing bar/bq &&
 509                 GIT_MERGE_VERBOSITY=3 git -c merge.directoryRenames=true merge -s recursive A^0 >out 2>err &&
 510
 511                 test_must_be_empty err &&
 512
 513                 test_path_is_file bar/bq &&
 514
 515                 git ls-files -s >index_files &&
 516                 test_line_count = 2 index_files &&
 517
 518                 git rev-parse >actual HEAD:bar/bq HEAD:bar/whatever &&
 519                 git rev-parse >expect A:foo/bq    A:foo/whatever &&
 520                 test_cmp expect actual &&
 521
 522                 git hash-object bar/bq   bar/whatever   >actual &&
 523                 git rev-parse   A:foo/bq A:foo/whatever >expect &&
 524                 test_cmp expect actual &&
 525
 526                 test_must_fail git rev-parse HEAD:bq HEAD:foo/bq &&
 527                 test_path_is_missing bq &&
 528                 test_path_is_missing foo/bq &&
 529                 test_path_is_missing foo/whatever
 530         )
 531 '
 532
 533 # Testcase 3b, rename into dir foo on A, dir rename foo->bar + change on B
 534 #   Commit O: bq_1, foo/whatever
 535 #   Commit A: foo/{bq_1, whatever}
 536 #   Commit B: bq_2, bar/whatever
 537 #   Expected: bar/{bq_2, whatever}
 538
 539 test_setup_3b () {
 540         test_create_repo 3b_$1 &&
 541         (
 542                 cd 3b_$1 &&
 543
 544                 mkdir foo &&
 545                 test_seq 1 10 >bq &&
 546                 test_write_lines a b c d e f g h i j k >foo/whatever &&
 547                 git add bq foo/whatever &&
 548                 test_tick &&
 549                 git commit -m "O" &&
 550
 551                 git branch O &&
 552                 git branch A &&
 553                 git branch B &&
 554
 555                 git checkout A &&
 556                 git mv bq foo/ &&
 557                 test_tick &&
 558                 git commit -m "A" &&
 559
 560                 git checkout B &&
 561                 test_seq 1 11 >bq &&
 562                 git add bq &&
 563                 git mv foo/ bar/ &&
 564                 test_tick &&
 565                 git commit -m "B"
 566         )
 567 }
 568
 569 test_expect_success '3b-L: bq_1->foo/bq_2 on A, foo/->bar/ on B' '
 570         test_setup_3b L &&
 571         (
 572                 cd 3b_L &&
 573
 574                 git checkout A^0 &&
 575
 576                 test_path_is_missing bar/bq &&
 577                 GIT_MERGE_VERBOSITY=3 git -c merge.directoryRenames=true merge -s recursive B^0 >out 2>err &&
 578
 579                 test_must_be_empty err &&
 580
 581                 test_path_is_file bar/bq &&
 582
 583                 git ls-files -s >index_files &&
 584                 test_line_count = 2 index_files &&
 585
 586                 git rev-parse >actual HEAD:bar/bq HEAD:bar/whatever &&
 587                 git rev-parse >expect B:bq        A:foo/whatever &&
 588                 test_cmp expect actual &&
 589
 590                 git hash-object bar/bq bar/whatever   >actual &&
 591                 git rev-parse   B:bq   A:foo/whatever >expect &&
 592                 test_cmp expect actual &&
 593
 594                 test_must_fail git rev-parse HEAD:bq HEAD:foo/bq &&
 595                 test_path_is_missing bq &&
 596                 test_path_is_missing foo/bq &&
 597                 test_path_is_missing foo/whatever
 598         )
 599 '
 600
 601 test_expect_success '3b-R: bq_1->foo/bq_2 on A, foo/->bar/ on B' '
 602         test_setup_3b R &&
 603         (
 604                 cd 3b_R &&
 605
 606                 git checkout B^0 &&
 607
 608                 test_path_is_missing bar/bq &&
 609                 GIT_MERGE_VERBOSITY=3 git -c merge.directoryRenames=true merge -s recursive A^0 >out 2>err &&
 610
 611                 test_must_be_empty err &&
 612
 613                 test_path_is_file bar/bq &&
 614
 615                 git ls-files -s >index_files &&
 616                 test_line_count = 2 index_files &&
 617
 618                 git rev-parse >actual HEAD:bar/bq HEAD:bar/whatever &&
 619                 git rev-parse >expect B:bq        A:foo/whatever &&
 620                 test_cmp expect actual &&
 621
 622                 git hash-object bar/bq bar/whatever   >actual &&
 623                 git rev-parse   B:bq   A:foo/whatever >expect &&
 624                 test_cmp expect actual &&
 625
 626                 test_must_fail git rev-parse HEAD:bq HEAD:foo/bq &&
 627                 test_path_is_missing bq &&
 628                 test_path_is_missing foo/bq &&
 629                 test_path_is_missing foo/whatever
 630         )
 631 '
 632
 633 ###########################################################################
 634 # SECTION 4: Cases involving dirty changes
 635 ###########################################################################
 636
 637 # Testcase 4a, Changed on A, subset of changes on B, locally modified
 638 #   Commit O: b_1
 639 #   Commit A: b_2
 640 #   Commit B: b_3
 641 #   Working copy: b_4
 642 #   Expected: b_2 for merge, b_4 in working copy
 643
 644 test_setup_4a () {
 645         test_create_repo 4a &&
 646         (
 647                 cd 4a &&
 648
 649                 test_write_lines 1 2 3 4 5 6 7 8 9 10 >b &&
 650                 git add b &&
 651                 test_tick &&
 652                 git commit -m "O" &&
 653
 654                 git branch O &&
 655                 git branch A &&
 656                 git branch B &&
 657
 658                 git checkout A &&
 659                 test_write_lines 1 2 3 4 5 5.5 6 7 8 9 10 10.5 >b &&
 660                 git add b &&
 661                 test_tick &&
 662                 git commit -m "A" &&
 663
 664                 git checkout B &&
 665                 test_write_lines 1 2 3 4 5 5.5 6 7 8 9 10 >b &&
 666                 git add b &&
 667                 test_tick &&
 668                 git commit -m "B"
 669         )
 670 }
 671
 672 # NOTE: For as long as we continue using unpack_trees() without index_only
 673 #   set to true, it will error out on a case like this claiming that the locally
 674 #   modified file would be overwritten by the merge.  Getting this testcase
 675 #   correct requires doing the merge in-memory first, then realizing that no
 676 #   updates to the file are necessary, and thus that we can just leave the path
 677 #   alone.
 678 test_expect_merge_algorithm failure success '4a: Change on A, change on B subset of A, dirty mods present' '
 679         test_setup_4a &&
 680         (
 681                 cd 4a &&
 682
 683                 git checkout A^0 &&
 684                 echo "File rewritten" >b &&
 685
 686                 test-tool chmtime --get -3600 b >old-mtime &&
 687
 688                 GIT_MERGE_VERBOSITY=3 git merge -s recursive B^0 >out 2>err &&
 689
 690                 test_must_be_empty err &&
 691
 692                 # Make sure b was NOT updated
 693                 test-tool chmtime --get b >new-mtime &&
 694                 test_cmp old-mtime new-mtime &&
 695
 696                 git ls-files -s >index_files &&
 697                 test_line_count = 1 index_files &&
 698
 699                 git rev-parse >actual :0:b &&
 700                 git rev-parse >expect A:b &&
 701                 test_cmp expect actual &&
 702
 703                 git hash-object b >actual &&
 704                 echo "File rewritten" | git hash-object --stdin >expect &&
 705                 test_cmp expect actual
 706         )
 707 '
 708
 709 # Testcase 4b, Changed+renamed on A, subset of changes on B, locally modified
 710 #   Commit O: b_1
 711 #   Commit A: c_2
 712 #   Commit B: b_3
 713 #   Working copy: c_4
 714 #   Expected: c_2
 715
 716 test_setup_4b () {
 717         test_create_repo 4b &&
 718         (
 719                 cd 4b &&
 720
 721                 test_write_lines 1 2 3 4 5 6 7 8 9 10 >b &&
 722                 git add b &&
 723                 test_tick &&
 724                 git commit -m "O" &&
 725
 726                 git branch O &&
 727                 git branch A &&
 728                 git branch B &&
 729
 730                 git checkout A &&
 731                 test_write_lines 1 2 3 4 5 5.5 6 7 8 9 10 10.5 >b &&
 732                 git add b &&
 733                 git mv b c &&
 734                 test_tick &&
 735                 git commit -m "A" &&
 736
 737                 git checkout B &&
 738                 test_write_lines 1 2 3 4 5 5.5 6 7 8 9 10 >b &&
 739                 git add b &&
 740                 test_tick &&
 741                 git commit -m "B"
 742         )
 743 }
 744
 745 test_expect_success '4b: Rename+Mod(A)/Mod(B), change on B subset of A, dirty mods present' '
 746         test_setup_4b &&
 747         (
 748                 cd 4b &&
 749
 750                 git checkout A^0 &&
 751                 echo "File rewritten" >c &&
 752
 753                 test-tool chmtime --get -3600 c >old-mtime &&
 754
 755                 GIT_MERGE_VERBOSITY=3 git merge -s recursive B^0 >out 2>err &&
 756
 757                 test_must_be_empty err &&
 758
 759                 # Make sure c was NOT updated
 760                 test-tool chmtime --get c >new-mtime &&
 761                 test_cmp old-mtime new-mtime &&
 762
 763                 git ls-files -s >index_files &&
 764                 test_line_count = 1 index_files &&
 765
 766                 git rev-parse >actual :0:c &&
 767                 git rev-parse >expect A:c &&
 768                 test_cmp expect actual &&
 769
 770                 git hash-object c >actual &&
 771                 echo "File rewritten" | git hash-object --stdin >expect &&
 772                 test_cmp expect actual &&
 773
 774                 test_must_fail git rev-parse HEAD:b &&
 775                 test_path_is_missing b
 776         )
 777 '
 778
 779 test_done