Andrew's git / gitweb.git / t/t6036-recursive-corner-cases.sh
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t / t6036-recursive-corner-cases.shon commit ll-merge: use a longer conflict marker for internal merge (d694a17)
   1#!/bin/sh
   2
   3test_description='recursive merge corner cases involving criss-cross merges'
   4
   5. ./test-lib.sh
   6
   7get_clean_checkout () {
   8        git reset --hard &&
   9        git clean -fdqx &&
  10        git checkout "$1"
  11}
  12
  13#
  14#  L1  L2
  15#   o---o
  16#  / \ / \
  17# o   X   ?
  18#  \ / \ /
  19#   o---o
  20#  R1  R2
  21#
  22
  23test_expect_success 'setup basic criss-cross + rename with no modifications' '
  24        ten="0 1 2 3 4 5 6 7 8 9" &&
  25        for i in $ten
  26        do
  27                echo line $i in a sample file
  28        done >one &&
  29        for i in $ten
  30        do
  31                echo line $i in another sample file
  32        done >two &&
  33        git add one two &&
  34        test_tick && git commit -m initial &&
  35
  36        git branch L1 &&
  37        git checkout -b R1 &&
  38        git mv one three &&
  39        test_tick && git commit -m R1 &&
  40
  41        git checkout L1 &&
  42        git mv two three &&
  43        test_tick && git commit -m L1 &&
  44
  45        git checkout L1^0 &&
  46        test_tick && git merge -s ours R1 &&
  47        git tag L2 &&
  48
  49        git checkout R1^0 &&
  50        test_tick && git merge -s ours L1 &&
  51        git tag R2
  52'
  53
  54test_expect_success 'merge simple rename+criss-cross with no modifications' '
  55        git reset --hard &&
  56        git checkout L2^0 &&
  57
  58        test_must_fail git merge -s recursive R2^0 &&
  59
  60        test 2 = $(git ls-files -s | wc -l) &&
  61        test 2 = $(git ls-files -u | wc -l) &&
  62        test 2 = $(git ls-files -o | wc -l) &&
  63
  64        test $(git rev-parse :2:three) = $(git rev-parse L2:three) &&
  65        test $(git rev-parse :3:three) = $(git rev-parse R2:three) &&
  66
  67        test $(git rev-parse L2:three) = $(git hash-object three~HEAD) &&
  68        test $(git rev-parse R2:three) = $(git hash-object three~R2^0)
  69'
  70
  71#
  72# Same as before, but modify L1 slightly:
  73#
  74#  L1m L2
  75#   o---o
  76#  / \ / \
  77# o   X   ?
  78#  \ / \ /
  79#   o---o
  80#  R1  R2
  81#
  82
  83test_expect_success 'setup criss-cross + rename merges with basic modification' '
  84        git rm -rf . &&
  85        git clean -fdqx &&
  86        rm -rf .git &&
  87        git init &&
  88
  89        ten="0 1 2 3 4 5 6 7 8 9"
  90        for i in $ten
  91        do
  92                echo line $i in a sample file
  93        done >one &&
  94        for i in $ten
  95        do
  96                echo line $i in another sample file
  97        done >two &&
  98        git add one two &&
  99        test_tick && git commit -m initial &&
 100
 101        git branch L1 &&
 102        git checkout -b R1 &&
 103        git mv one three &&
 104        echo more >>two &&
 105        git add two &&
 106        test_tick && git commit -m R1 &&
 107
 108        git checkout L1 &&
 109        git mv two three &&
 110        test_tick && git commit -m L1 &&
 111
 112        git checkout L1^0 &&
 113        test_tick && git merge -s ours R1 &&
 114        git tag L2 &&
 115
 116        git checkout R1^0 &&
 117        test_tick && git merge -s ours L1 &&
 118        git tag R2
 119'
 120
 121test_expect_success 'merge criss-cross + rename merges with basic modification' '
 122        git reset --hard &&
 123        git checkout L2^0 &&
 124
 125        test_must_fail git merge -s recursive R2^0 &&
 126
 127        test 2 = $(git ls-files -s | wc -l) &&
 128        test 2 = $(git ls-files -u | wc -l) &&
 129        test 2 = $(git ls-files -o | wc -l) &&
 130
 131        test $(git rev-parse :2:three) = $(git rev-parse L2:three) &&
 132        test $(git rev-parse :3:three) = $(git rev-parse R2:three) &&
 133
 134        test $(git rev-parse L2:three) = $(git hash-object three~HEAD) &&
 135        test $(git rev-parse R2:three) = $(git hash-object three~R2^0)
 136'
 137
 138#
 139# For the next test, we start with three commits in two lines of development
 140# which setup a rename/add conflict:
 141#   Commit A: File 'a' exists
 142#   Commit B: Rename 'a' -> 'new_a'
 143#   Commit C: Modify 'a', create different 'new_a'
 144# Later, two different people merge and resolve differently:
 145#   Commit D: Merge B & C, ignoring separately created 'new_a'
 146#   Commit E: Merge B & C making use of some piece of secondary 'new_a'
 147# Finally, someone goes to merge D & E.  Does git detect the conflict?
 148#
 149#      B   D
 150#      o---o
 151#     / \ / \
 152#  A o   X   ? F
 153#     \ / \ /
 154#      o---o
 155#      C   E
 156#
 157
 158test_expect_success 'setup differently handled merges of rename/add conflict' '
 159        git rm -rf . &&
 160        git clean -fdqx &&
 161        rm -rf .git &&
 162        git init &&
 163
 164        printf "0\n1\n2\n3\n4\n5\n6\n7\n8\n9\n" >a &&
 165        git add a &&
 166        test_tick && git commit -m A &&
 167
 168        git branch B &&
 169        git checkout -b C &&
 170        echo 10 >>a &&
 171        echo "other content" >>new_a &&
 172        git add a new_a &&
 173        test_tick && git commit -m C &&
 174
 175        git checkout B &&
 176        git mv a new_a &&
 177        test_tick && git commit -m B &&
 178
 179        git checkout B^0 &&
 180        test_must_fail git merge C &&
 181        git clean -f &&
 182        test_tick && git commit -m D &&
 183        git tag D &&
 184
 185        git checkout C^0 &&
 186        test_must_fail git merge B &&
 187        rm new_a~HEAD new_a &&
 188        printf "Incorrectly merged content" >>new_a &&
 189        git add -u &&
 190        test_tick && git commit -m E &&
 191        git tag E
 192'
 193
 194test_expect_success 'git detects differently handled merges conflict' '
 195        git reset --hard &&
 196        git checkout D^0 &&
 197
 198        git merge -s recursive E^0 && {
 199                echo "BAD: should have conflicted"
 200                test "Incorrectly merged content" = "$(cat new_a)" &&
 201                        echo "BAD: Silently accepted wrong content"
 202                return 1
 203        }
 204
 205        test 3 = $(git ls-files -s | wc -l) &&
 206        test 3 = $(git ls-files -u | wc -l) &&
 207        test 0 = $(git ls-files -o | wc -l) &&
 208
 209        test $(git rev-parse :2:new_a) = $(git rev-parse D:new_a) &&
 210        test $(git rev-parse :3:new_a) = $(git rev-parse E:new_a) &&
 211
 212        git cat-file -p B:new_a >>merged &&
 213        git cat-file -p C:new_a >>merge-me &&
 214        >empty &&
 215        test_must_fail git merge-file \
 216                -L "Temporary merge branch 2" \
 217                -L "" \
 218                -L "Temporary merge branch 1" \
 219                merged empty merge-me &&
 220        sed -e "s/^\([<=>]\)/\1\1\1/" merged >merged-internal &&
 221        test $(git rev-parse :1:new_a) = $(git hash-object merged-internal)
 222'
 223
 224#
 225# criss-cross + modify/delete:
 226#
 227#      B   D
 228#      o---o
 229#     / \ / \
 230#  A o   X   ? F
 231#     \ / \ /
 232#      o---o
 233#      C   E
 234#
 235#   Commit A: file with contents 'A\n'
 236#   Commit B: file with contents 'B\n'
 237#   Commit C: file not present
 238#   Commit D: file with contents 'B\n'
 239#   Commit E: file not present
 240#
 241# Merging commits D & E should result in modify/delete conflict.
 242
 243test_expect_success 'setup criss-cross + modify/delete resolved differently' '
 244        git rm -rf . &&
 245        git clean -fdqx &&
 246        rm -rf .git &&
 247        git init &&
 248
 249        echo A >file &&
 250        git add file &&
 251        test_tick &&
 252        git commit -m A &&
 253
 254        git branch B &&
 255        git checkout -b C &&
 256        git rm file &&
 257        test_tick &&
 258        git commit -m C &&
 259
 260        git checkout B &&
 261        echo B >file &&
 262        git add file &&
 263        test_tick &&
 264        git commit -m B &&
 265
 266        git checkout B^0 &&
 267        test_must_fail git merge C &&
 268        echo B >file &&
 269        git add file &&
 270        test_tick &&
 271        git commit -m D &&
 272        git tag D &&
 273
 274        git checkout C^0 &&
 275        test_must_fail git merge B &&
 276        git rm file &&
 277        test_tick &&
 278        git commit -m E &&
 279        git tag E
 280'
 281
 282test_expect_success 'git detects conflict merging criss-cross+modify/delete' '
 283        git checkout D^0 &&
 284
 285        test_must_fail git merge -s recursive E^0 &&
 286
 287        test 2 -eq $(git ls-files -s | wc -l) &&
 288        test 2 -eq $(git ls-files -u | wc -l) &&
 289
 290        test $(git rev-parse :1:file) = $(git rev-parse master:file) &&
 291        test $(git rev-parse :2:file) = $(git rev-parse B:file)
 292'
 293
 294test_expect_success 'git detects conflict merging criss-cross+modify/delete, reverse direction' '
 295        git reset --hard &&
 296        git checkout E^0 &&
 297
 298        test_must_fail git merge -s recursive D^0 &&
 299
 300        test 2 -eq $(git ls-files -s | wc -l) &&
 301        test 2 -eq $(git ls-files -u | wc -l) &&
 302
 303        test $(git rev-parse :1:file) = $(git rev-parse master:file) &&
 304        test $(git rev-parse :3:file) = $(git rev-parse B:file)
 305'
 306
 307#
 308# criss-cross + modify/modify with very contrived file contents:
 309#
 310#      B   D
 311#      o---o
 312#     / \ / \
 313#  A o   X   ? F
 314#     \ / \ /
 315#      o---o
 316#      C   E
 317#
 318#   Commit A: file with contents 'A\n'
 319#   Commit B: file with contents 'B\n'
 320#   Commit C: file with contents 'C\n'
 321#   Commit D: file with contents 'D\n'
 322#   Commit E: file with contents:
 323#      <<<<<<< Temporary merge branch 1
 324#      C
 325#      =======
 326#      B
 327#      >>>>>>> Temporary merge branch 2
 328#
 329# Now, when we merge commits D & E, does git detect the conflict?
 330
 331test_expect_success 'setup differently handled merges of content conflict' '
 332        git clean -fdqx &&
 333        rm -rf .git &&
 334        git init &&
 335
 336        echo A >file &&
 337        git add file &&
 338        test_tick &&
 339        git commit -m A &&
 340
 341        git branch B &&
 342        git checkout -b C &&
 343        echo C >file &&
 344        git add file &&
 345        test_tick &&
 346        git commit -m C &&
 347
 348        git checkout B &&
 349        echo B >file &&
 350        git add file &&
 351        test_tick &&
 352        git commit -m B &&
 353
 354        git checkout B^0 &&
 355        test_must_fail git merge C &&
 356        echo D >file &&
 357        git add file &&
 358        test_tick &&
 359        git commit -m D &&
 360        git tag D &&
 361
 362        git checkout C^0 &&
 363        test_must_fail git merge B &&
 364        cat <<EOF >file &&
 365<<<<<<< Temporary merge branch 1
 366C
 367=======
 368B
 369>>>>>>> Temporary merge branch 2
 370EOF
 371        git add file &&
 372        test_tick &&
 373        git commit -m E &&
 374        git tag E
 375'
 376
 377test_expect_failure 'git detects conflict w/ criss-cross+contrived resolution' '
 378        git checkout D^0 &&
 379
 380        test_must_fail git merge -s recursive E^0 &&
 381
 382        test 3 -eq $(git ls-files -s | wc -l) &&
 383        test 3 -eq $(git ls-files -u | wc -l) &&
 384        test 0 -eq $(git ls-files -o | wc -l) &&
 385
 386        test $(git rev-parse :2:file) = $(git rev-parse D:file) &&
 387        test $(git rev-parse :3:file) = $(git rev-parse E:file)
 388'
 389
 390#
 391# criss-cross + d/f conflict via add/add:
 392#   Commit A: Neither file 'a' nor directory 'a/' exists.
 393#   Commit B: Introduce 'a'
 394#   Commit C: Introduce 'a/file'
 395#   Commit D: Merge B & C, keeping 'a' and deleting 'a/'
 396#
 397# Two different later cases:
 398#   Commit E1: Merge B & C, deleting 'a' but keeping 'a/file'
 399#   Commit E2: Merge B & C, deleting 'a' but keeping a slightly modified 'a/file'
 400#
 401#      B   D
 402#      o---o
 403#     / \ / \
 404#  A o   X   ? F
 405#     \ / \ /
 406#      o---o
 407#      C   E1 or E2
 408#
 409# Merging D & E1 requires we first create a virtual merge base X from
 410# merging A & B in memory.  Now, if X could keep both 'a' and 'a/file' in
 411# the index, then the merge of D & E1 could be resolved cleanly with both
 412# 'a' and 'a/file' removed.  Since git does not currently allow creating
 413# such a tree, the best we can do is have X contain both 'a~<unique>' and
 414# 'a/file' resulting in the merge of D and E1 having a rename/delete
 415# conflict for 'a'.  (Although this merge appears to be unsolvable with git
 416# currently, git could do a lot better than it currently does with these
 417# d/f conflicts, which is the purpose of this test.)
 418#
 419# Merge of D & E2 has similar issues for path 'a', but should always result
 420# in a modify/delete conflict for path 'a/file'.
 421#
 422# We run each merge in both directions, to check for directional issues
 423# with D/F conflict handling.
 424#
 425
 426test_expect_success 'setup differently handled merges of directory/file conflict' '
 427        git rm -rf . &&
 428        git clean -fdqx &&
 429        rm -rf .git &&
 430        git init &&
 431
 432        >ignore-me &&
 433        git add ignore-me &&
 434        test_tick &&
 435        git commit -m A &&
 436        git tag A &&
 437
 438        git branch B &&
 439        git checkout -b C &&
 440        mkdir a &&
 441        echo 10 >a/file &&
 442        git add a/file &&
 443        test_tick &&
 444        git commit -m C &&
 445
 446        git checkout B &&
 447        echo 5 >a &&
 448        git add a &&
 449        test_tick &&
 450        git commit -m B &&
 451
 452        git checkout B^0 &&
 453        test_must_fail git merge C &&
 454        git clean -f &&
 455        rm -rf a/ &&
 456        echo 5 >a &&
 457        git add a &&
 458        test_tick &&
 459        git commit -m D &&
 460        git tag D &&
 461
 462        git checkout C^0 &&
 463        test_must_fail git merge B &&
 464        git clean -f &&
 465        git rm --cached a &&
 466        echo 10 >a/file &&
 467        git add a/file &&
 468        test_tick &&
 469        git commit -m E1 &&
 470        git tag E1 &&
 471
 472        git checkout C^0 &&
 473        test_must_fail git merge B &&
 474        git clean -f &&
 475        git rm --cached a &&
 476        printf "10\n11\n" >a/file &&
 477        git add a/file &&
 478        test_tick &&
 479        git commit -m E2 &&
 480        git tag E2
 481'
 482
 483test_expect_success 'merge of D & E1 fails but has appropriate contents' '
 484        get_clean_checkout D^0 &&
 485
 486        test_must_fail git merge -s recursive E1^0 &&
 487
 488        test 2 -eq $(git ls-files -s | wc -l) &&
 489        test 1 -eq $(git ls-files -u | wc -l) &&
 490        test 0 -eq $(git ls-files -o | wc -l) &&
 491
 492        test $(git rev-parse :0:ignore-me) = $(git rev-parse A:ignore-me) &&
 493        test $(git rev-parse :2:a) = $(git rev-parse B:a)
 494'
 495
 496test_expect_success 'merge of E1 & D fails but has appropriate contents' '
 497        get_clean_checkout E1^0 &&
 498
 499        test_must_fail git merge -s recursive D^0 &&
 500
 501        test 2 -eq $(git ls-files -s | wc -l) &&
 502        test 1 -eq $(git ls-files -u | wc -l) &&
 503        test 0 -eq $(git ls-files -o | wc -l) &&
 504
 505        test $(git rev-parse :0:ignore-me) = $(git rev-parse A:ignore-me) &&
 506        test $(git rev-parse :3:a) = $(git rev-parse B:a)
 507'
 508
 509test_expect_success 'merge of D & E2 fails but has appropriate contents' '
 510        get_clean_checkout D^0 &&
 511
 512        test_must_fail git merge -s recursive E2^0 &&
 513
 514        test 4 -eq $(git ls-files -s | wc -l) &&
 515        test 3 -eq $(git ls-files -u | wc -l) &&
 516        test 1 -eq $(git ls-files -o | wc -l) &&
 517
 518        test $(git rev-parse :2:a) = $(git rev-parse B:a) &&
 519        test $(git rev-parse :3:a/file) = $(git rev-parse E2:a/file) &&
 520        test $(git rev-parse :1:a/file) = $(git rev-parse C:a/file) &&
 521        test $(git rev-parse :0:ignore-me) = $(git rev-parse A:ignore-me) &&
 522
 523        test -f a~HEAD
 524'
 525
 526test_expect_success 'merge of E2 & D fails but has appropriate contents' '
 527        get_clean_checkout E2^0 &&
 528
 529        test_must_fail git merge -s recursive D^0 &&
 530
 531        test 4 -eq $(git ls-files -s | wc -l) &&
 532        test 3 -eq $(git ls-files -u | wc -l) &&
 533        test 1 -eq $(git ls-files -o | wc -l) &&
 534
 535        test $(git rev-parse :3:a) = $(git rev-parse B:a) &&
 536        test $(git rev-parse :2:a/file) = $(git rev-parse E2:a/file) &&
 537        test $(git rev-parse :1:a/file) = $(git rev-parse C:a/file)
 538        test $(git rev-parse :0:ignore-me) = $(git rev-parse A:ignore-me) &&
 539
 540        test -f a~D^0
 541'
 542
 543#
 544# criss-cross with rename/rename(1to2)/modify followed by
 545# rename/rename(2to1)/modify:
 546#
 547#      B   D
 548#      o---o
 549#     / \ / \
 550#  A o   X   ? F
 551#     \ / \ /
 552#      o---o
 553#      C   E
 554#
 555#   Commit A: new file: a
 556#   Commit B: rename a->b, modifying by adding a line
 557#   Commit C: rename a->c
 558#   Commit D: merge B&C, resolving conflict by keeping contents in newname
 559#   Commit E: merge B&C, resolving conflict similar to D but adding another line
 560#
 561# There is a conflict merging B & C, but one of filename not of file
 562# content.  Whoever created D and E chose specific resolutions for that
 563# conflict resolution.  Now, since: (1) there is no content conflict
 564# merging B & C, (2) D does not modify that merged content further, and (3)
 565# both D & E resolve the name conflict in the same way, the modification to
 566# newname in E should not cause any conflicts when it is merged with D.
 567# (Note that this can be accomplished by having the virtual merge base have
 568# the merged contents of b and c stored in a file named a, which seems like
 569# the most logical choice anyway.)
 570#
 571# Comment from Junio: I do not necessarily agree with the choice "a", but
 572# it feels sound to say "B and C do not agree what the final pathname
 573# should be, but we know this content was derived from the common A:a so we
 574# use one path whose name is arbitrary in the virtual merge base X between
 575# D and E" and then further let the rename detection to notice that that
 576# arbitrary path gets renamed between X-D to "newname" and X-E also to
 577# "newname" to resolve it as both sides renaming it to the same new
 578# name. It is akin to what we do at the content level, i.e. "B and C do not
 579# agree what the final contents should be, so we leave the conflict marker
 580# but that may cancel out at the final merge stage".
 581
 582test_expect_success 'setup rename/rename(1to2)/modify followed by what looks like rename/rename(2to1)/modify' '
 583        git reset --hard &&
 584        git rm -rf . &&
 585        git clean -fdqx &&
 586        rm -rf .git &&
 587        git init &&
 588
 589        printf "1\n2\n3\n4\n5\n6\n" >a &&
 590        git add a &&
 591        git commit -m A &&
 592        git tag A &&
 593
 594        git checkout -b B A &&
 595        git mv a b &&
 596        echo 7 >>b &&
 597        git add -u &&
 598        git commit -m B &&
 599
 600        git checkout -b C A &&
 601        git mv a c &&
 602        git commit -m C &&
 603
 604        git checkout -q B^0 &&
 605        git merge --no-commit -s ours C^0 &&
 606        git mv b newname &&
 607        git commit -m "Merge commit C^0 into HEAD" &&
 608        git tag D &&
 609
 610        git checkout -q C^0 &&
 611        git merge --no-commit -s ours B^0 &&
 612        git mv c newname &&
 613        printf "7\n8\n" >>newname &&
 614        git add -u &&
 615        git commit -m "Merge commit B^0 into HEAD" &&
 616        git tag E
 617'
 618
 619test_expect_success 'handle rename/rename(1to2)/modify followed by what looks like rename/rename(2to1)/modify' '
 620        git checkout D^0 &&
 621
 622        git merge -s recursive E^0 &&
 623
 624        test 1 -eq $(git ls-files -s | wc -l) &&
 625        test 0 -eq $(git ls-files -u | wc -l) &&
 626        test 0 -eq $(git ls-files -o | wc -l) &&
 627
 628        test $(git rev-parse HEAD:newname) = $(git rev-parse E:newname)
 629'
 630
 631#
 632# criss-cross with rename/rename(1to2)/add-source + resolvable modify/modify:
 633#
 634#      B   D
 635#      o---o
 636#     / \ / \
 637#  A o   X   ? F
 638#     \ / \ /
 639#      o---o
 640#      C   E
 641#
 642#   Commit A: new file: a
 643#   Commit B: rename a->b
 644#   Commit C: rename a->c, add different a
 645#   Commit D: merge B&C, keeping b&c and (new) a modified at beginning
 646#   Commit E: merge B&C, keeping b&c and (new) a modified at end
 647#
 648# Merging commits D & E should result in no conflict; doing so correctly
 649# requires getting the virtual merge base (from merging B&C) right, handling
 650# renaming carefully (both in the virtual merge base and later), and getting
 651# content merge handled.
 652
 653test_expect_success 'setup criss-cross + rename/rename/add + modify/modify' '
 654        git rm -rf . &&
 655        git clean -fdqx &&
 656        rm -rf .git &&
 657        git init &&
 658
 659        printf "lots\nof\nwords\nand\ncontent\n" >a &&
 660        git add a &&
 661        git commit -m A &&
 662        git tag A &&
 663
 664        git checkout -b B A &&
 665        git mv a b &&
 666        git commit -m B &&
 667
 668        git checkout -b C A &&
 669        git mv a c &&
 670        printf "2\n3\n4\n5\n6\n7\n" >a &&
 671        git add a &&
 672        git commit -m C &&
 673
 674        git checkout B^0 &&
 675        git merge --no-commit -s ours C^0 &&
 676        git checkout C -- a c &&
 677        mv a old_a &&
 678        echo 1 >a &&
 679        cat old_a >>a &&
 680        rm old_a &&
 681        git add -u &&
 682        git commit -m "Merge commit C^0 into HEAD" &&
 683        git tag D &&
 684
 685        git checkout C^0 &&
 686        git merge --no-commit -s ours B^0 &&
 687        git checkout B -- b &&
 688        echo 8 >>a &&
 689        git add -u &&
 690        git commit -m "Merge commit B^0 into HEAD" &&
 691        git tag E
 692'
 693
 694test_expect_failure 'detect rename/rename/add-source for virtual merge-base' '
 695        git checkout D^0 &&
 696
 697        git merge -s recursive E^0 &&
 698
 699        test 3 -eq $(git ls-files -s | wc -l) &&
 700        test 0 -eq $(git ls-files -u | wc -l) &&
 701        test 0 -eq $(git ls-files -o | wc -l) &&
 702
 703        test $(git rev-parse HEAD:b) = $(git rev-parse A:a) &&
 704        test $(git rev-parse HEAD:c) = $(git rev-parse A:a) &&
 705        test "$(cat a)" = "$(printf "1\n2\n3\n4\n5\n6\n7\n8\n")"
 706'
 707
 708#
 709# criss-cross with rename/rename(1to2)/add-dest + simple modify:
 710#
 711#      B   D
 712#      o---o
 713#     / \ / \
 714#  A o   X   ? F
 715#     \ / \ /
 716#      o---o
 717#      C   E
 718#
 719#   Commit A: new file: a
 720#   Commit B: rename a->b, add c
 721#   Commit C: rename a->c
 722#   Commit D: merge B&C, keeping A:a and B:c
 723#   Commit E: merge B&C, keeping A:a and slightly modified c from B
 724#
 725# Merging commits D & E should result in no conflict.  The virtual merge
 726# base of B & C needs to not delete B:c for that to work, though...
 727
 728test_expect_success 'setup criss-cross+rename/rename/add-dest + simple modify' '
 729        git rm -rf . &&
 730        git clean -fdqx &&
 731        rm -rf .git &&
 732        git init &&
 733
 734        >a &&
 735        git add a &&
 736        git commit -m A &&
 737        git tag A &&
 738
 739        git checkout -b B A &&
 740        git mv a b &&
 741        printf "1\n2\n3\n4\n5\n6\n7\n" >c &&
 742        git add c &&
 743        git commit -m B &&
 744
 745        git checkout -b C A &&
 746        git mv a c &&
 747        git commit -m C &&
 748
 749        git checkout B^0 &&
 750        git merge --no-commit -s ours C^0 &&
 751        git mv b a &&
 752        git commit -m "D is like B but renames b back to a" &&
 753        git tag D &&
 754
 755        git checkout B^0 &&
 756        git merge --no-commit -s ours C^0 &&
 757        git mv b a &&
 758        echo 8 >>c &&
 759        git add c &&
 760        git commit -m "E like D but has mod in c" &&
 761        git tag E
 762'
 763
 764test_expect_success 'virtual merge base handles rename/rename(1to2)/add-dest' '
 765        git checkout D^0 &&
 766
 767        git merge -s recursive E^0 &&
 768
 769        test 2 -eq $(git ls-files -s | wc -l) &&
 770        test 0 -eq $(git ls-files -u | wc -l) &&
 771        test 0 -eq $(git ls-files -o | wc -l) &&
 772
 773        test $(git rev-parse HEAD:a) = $(git rev-parse A:a) &&
 774        test $(git rev-parse HEAD:c) = $(git rev-parse E:c)
 775'
 776
 777test_done