t/t7600-merge.sh

   1 #!/bin/sh
   2 #
   3 # Copyright (c) 2007 Lars Hjemli
   4 #
   5
   6 test_description='git merge
   7
   8 Testing basic merge operations/option parsing.
   9
  10 ! [c0] commit 0
  11  ! [c1] commit 1
  12   ! [c2] commit 2
  13    ! [c3] commit 3
  14     ! [c4] c4
  15      ! [c5] c5
  16       ! [c6] c6
  17        * [master] Merge commit 'c1'
  18 --------
  19        - [master] Merge commit 'c1'
  20  +     * [c1] commit 1
  21       +  [c6] c6
  22      +   [c5] c5
  23     ++   [c4] c4
  24    ++++  [c3] commit 3
  25   +      [c2] commit 2
  26 +++++++* [c0] commit 0
  27 '
  28
  29 . ./test-lib.sh
  30 . "$TEST_DIRECTORY"/lib-gpg.sh
  31
  32 printf '%s\n' 1 2 3 4 5 6 7 8 9 >file
  33 printf '%s\n' '1 X' 2 3 4 5 6 7 8 9 >file.1
  34 printf '%s\n' 1 2 3 4 '5 X' 6 7 8 9 >file.5
  35 printf '%s\n' 1 2 3 4 5 6 7 8 '9 X' >file.9
  36 printf '%s\n' '1 X' 2 3 4 5 6 7 8 9 >result.1
  37 printf '%s\n' '1 X' 2 3 4 '5 X' 6 7 8 9 >result.1-5
  38 printf '%s\n' '1 X' 2 3 4 '5 X' 6 7 8 '9 X' >result.1-5-9
  39 >empty
  40
  41 create_merge_msgs () {
  42         echo "Merge tag 'c2'" >msg.1-5 &&
  43         echo "Merge tags 'c2' and 'c3'" >msg.1-5-9 &&
  44         {
  45                 echo "Squashed commit of the following:" &&
  46                 echo &&
  47                 git log --no-merges ^HEAD c1
  48         } >squash.1 &&
  49         {
  50                 echo "Squashed commit of the following:" &&
  51                 echo &&
  52                 git log --no-merges ^HEAD c2
  53         } >squash.1-5 &&
  54         {
  55                 echo "Squashed commit of the following:" &&
  56                 echo &&
  57                 git log --no-merges ^HEAD c2 c3
  58         } >squash.1-5-9 &&
  59         : >msg.nologff &&
  60         echo >msg.nolognoff &&
  61         {
  62                 echo "* tag 'c3':" &&
  63                 echo "  commit 3" &&
  64                 echo
  65         } >msg.log
  66 }
  67
  68 verify_merge () {
  69         test_cmp "$2" "$1" &&
  70         git update-index --refresh &&
  71         git diff --exit-code &&
  72         if test -n "$3"
  73         then
  74                 git show -s --pretty=format:%s HEAD >msg.act &&
  75                 test_cmp "$3" msg.act
  76         fi
  77 }
  78
  79 verify_head () {
  80         echo "$1" >head.expected &&
  81         git rev-parse HEAD >head.actual &&
  82         test_cmp head.expected head.actual
  83 }
  84
  85 verify_parents () {
  86         printf '%s\n' "$@" >parents.expected &&
  87         >parents.actual &&
  88         i=1 &&
  89         while test $i -le $#
  90         do
  91                 git rev-parse HEAD^$i >>parents.actual &&
  92                 i=$(expr $i + 1) ||
  93                 return 1
  94         done &&
  95         test_must_fail git rev-parse --verify "HEAD^$i" &&
  96         test_cmp parents.expected parents.actual
  97 }
  98
  99 verify_mergeheads () {
 100         printf '%s\n' "$@" >mergehead.expected &&
 101         while read sha1 rest
 102         do
 103                 git rev-parse $sha1
 104         done <.git/MERGE_HEAD >mergehead.actual &&
 105         test_cmp mergehead.expected mergehead.actual
 106 }
 107
 108 verify_no_mergehead () {
 109         ! test -e .git/MERGE_HEAD
 110 }
 111
 112 test_expect_success 'setup' '
 113         git add file &&
 114         test_tick &&
 115         git commit -m "commit 0" &&
 116         git tag c0 &&
 117         c0=$(git rev-parse HEAD) &&
 118         cp file.1 file &&
 119         git add file &&
 120         test_tick &&
 121         git commit -m "commit 1" &&
 122         git tag c1 &&
 123         c1=$(git rev-parse HEAD) &&
 124         git reset --hard "$c0" &&
 125         cp file.5 file &&
 126         git add file &&
 127         test_tick &&
 128         git commit -m "commit 2" &&
 129         git tag c2 &&
 130         c2=$(git rev-parse HEAD) &&
 131         git reset --hard "$c0" &&
 132         cp file.9 file &&
 133         git add file &&
 134         test_tick &&
 135         git commit -m "commit 3" &&
 136         git tag c3 &&
 137         c3=$(git rev-parse HEAD)
 138         git reset --hard "$c0" &&
 139         create_merge_msgs
 140 '
 141
 142 test_debug 'git log --graph --decorate --oneline --all'
 143
 144 test_expect_success 'test option parsing' '
 145         test_must_fail git merge -$ c1 &&
 146         test_must_fail git merge --no-such c1 &&
 147         test_must_fail git merge -s foobar c1 &&
 148         test_must_fail git merge -s=foobar c1 &&
 149         test_must_fail git merge -m &&
 150         test_must_fail git merge
 151 '
 152
 153 test_expect_success 'merge -h with invalid index' '
 154         mkdir broken &&
 155         (
 156                 cd broken &&
 157                 git init &&
 158                 >.git/index &&
 159                 test_expect_code 129 git merge -h 2>usage
 160         ) &&
 161         test_i18ngrep "[Uu]sage: git merge" broken/usage
 162 '
 163
 164 test_expect_success 'reject non-strategy with a git-merge-foo name' '
 165         test_must_fail git merge -s index c1
 166 '
 167
 168 test_expect_success 'merge c0 with c1' '
 169         echo "OBJID HEAD@{0}: merge c1: Fast-forward" >reflog.expected &&
 170
 171         git reset --hard c0 &&
 172         git merge c1 &&
 173         verify_merge file result.1 &&
 174         verify_head "$c1" &&
 175
 176         git reflog -1 >reflog.actual &&
 177         sed "s/$_x05[0-9a-f]*/OBJID/g" reflog.actual >reflog.fuzzy &&
 178         test_cmp reflog.expected reflog.fuzzy
 179 '
 180
 181 test_debug 'git log --graph --decorate --oneline --all'
 182
 183 test_expect_success 'merge c0 with c1 with --ff-only' '
 184         git reset --hard c0 &&
 185         git merge --ff-only c1 &&
 186         git merge --ff-only HEAD c0 c1 &&
 187         verify_merge file result.1 &&
 188         verify_head "$c1"
 189 '
 190
 191 test_debug 'git log --graph --decorate --oneline --all'
 192
 193 test_expect_success 'merge from unborn branch' '
 194         git checkout -f master &&
 195         test_might_fail git branch -D kid &&
 196
 197         echo "OBJID HEAD@{0}: initial pull" >reflog.expected &&
 198
 199         git checkout --orphan kid &&
 200         test_when_finished "git checkout -f master" &&
 201         git rm -fr . &&
 202         test_tick &&
 203         git merge --ff-only c1 &&
 204         verify_merge file result.1 &&
 205         verify_head "$c1" &&
 206
 207         git reflog -1 >reflog.actual &&
 208         sed "s/$_x05[0-9a-f][0-9a-f]/OBJID/g" reflog.actual >reflog.fuzzy &&
 209         test_cmp reflog.expected reflog.fuzzy
 210 '
 211
 212 test_debug 'git log --graph --decorate --oneline --all'
 213
 214 test_expect_success 'merge c1 with c2' '
 215         git reset --hard c1 &&
 216         test_tick &&
 217         git merge c2 &&
 218         verify_merge file result.1-5 msg.1-5 &&
 219         verify_parents $c1 $c2
 220 '
 221
 222 test_debug 'git log --graph --decorate --oneline --all'
 223
 224 test_expect_success 'merge c1 with c2 and c3' '
 225         git reset --hard c1 &&
 226         test_tick &&
 227         git merge c2 c3 &&
 228         verify_merge file result.1-5-9 msg.1-5-9 &&
 229         verify_parents $c1 $c2 $c3
 230 '
 231
 232 test_debug 'git log --graph --decorate --oneline --all'
 233
 234 test_expect_success 'merges with --ff-only' '
 235         git reset --hard c1 &&
 236         test_tick &&
 237         test_must_fail git merge --ff-only c2 &&
 238         test_must_fail git merge --ff-only c3 &&
 239         test_must_fail git merge --ff-only c2 c3 &&
 240         git reset --hard c0 &&
 241         git merge c3 &&
 242         verify_head $c3
 243 '
 244
 245 test_expect_success 'merges with merge.ff=only' '
 246         git reset --hard c1 &&
 247         test_tick &&
 248         test_config merge.ff "only" &&
 249         test_must_fail git merge c2 &&
 250         test_must_fail git merge c3 &&
 251         test_must_fail git merge c2 c3 &&
 252         git reset --hard c0 &&
 253         git merge c3 &&
 254         verify_head $c3
 255 '
 256
 257 test_expect_success 'merge c0 with c1 (no-commit)' '
 258         git reset --hard c0 &&
 259         git merge --no-commit c1 &&
 260         verify_merge file result.1 &&
 261         verify_head $c1
 262 '
 263
 264 test_debug 'git log --graph --decorate --oneline --all'
 265
 266 test_expect_success 'merge c1 with c2 (no-commit)' '
 267         git reset --hard c1 &&
 268         git merge --no-commit c2 &&
 269         verify_merge file result.1-5 &&
 270         verify_head $c1 &&
 271         verify_mergeheads $c2
 272 '
 273
 274 test_debug 'git log --graph --decorate --oneline --all'
 275
 276 test_expect_success 'merge c1 with c2 and c3 (no-commit)' '
 277         git reset --hard c1 &&
 278         git merge --no-commit c2 c3 &&
 279         verify_merge file result.1-5-9 &&
 280         verify_head $c1 &&
 281         verify_mergeheads $c2 $c3
 282 '
 283
 284 test_debug 'git log --graph --decorate --oneline --all'
 285
 286 test_expect_success 'merge c0 with c1 (squash)' '
 287         git reset --hard c0 &&
 288         git merge --squash c1 &&
 289         verify_merge file result.1 &&
 290         verify_head $c0 &&
 291         verify_no_mergehead &&
 292         test_cmp squash.1 .git/SQUASH_MSG
 293 '
 294
 295 test_debug 'git log --graph --decorate --oneline --all'
 296
 297 test_expect_success 'merge c0 with c1 (squash, ff-only)' '
 298         git reset --hard c0 &&
 299         git merge --squash --ff-only c1 &&
 300         verify_merge file result.1 &&
 301         verify_head $c0 &&
 302         verify_no_mergehead &&
 303         test_cmp squash.1 .git/SQUASH_MSG
 304 '
 305
 306 test_debug 'git log --graph --decorate --oneline --all'
 307
 308 test_expect_success 'merge c1 with c2 (squash)' '
 309         git reset --hard c1 &&
 310         git merge --squash c2 &&
 311         verify_merge file result.1-5 &&
 312         verify_head $c1 &&
 313         verify_no_mergehead &&
 314         test_cmp squash.1-5 .git/SQUASH_MSG
 315 '
 316
 317 test_debug 'git log --graph --decorate --oneline --all'
 318
 319 test_expect_success 'unsuccessful merge of c1 with c2 (squash, ff-only)' '
 320         git reset --hard c1 &&
 321         test_must_fail git merge --squash --ff-only c2
 322 '
 323
 324 test_debug 'git log --graph --decorate --oneline --all'
 325
 326 test_expect_success 'merge c1 with c2 and c3 (squash)' '
 327         git reset --hard c1 &&
 328         git merge --squash c2 c3 &&
 329         verify_merge file result.1-5-9 &&
 330         verify_head $c1 &&
 331         verify_no_mergehead &&
 332         test_cmp squash.1-5-9 .git/SQUASH_MSG
 333 '
 334
 335 test_debug 'git log --graph --decorate --oneline --all'
 336
 337 test_expect_success 'merge c1 with c2 (no-commit in config)' '
 338         git reset --hard c1 &&
 339         test_config branch.master.mergeoptions "--no-commit" &&
 340         git merge c2 &&
 341         verify_merge file result.1-5 &&
 342         verify_head $c1 &&
 343         verify_mergeheads $c2
 344 '
 345
 346 test_debug 'git log --graph --decorate --oneline --all'
 347
 348 test_expect_success 'merge c1 with c2 (log in config)' '
 349         git reset --hard c1 &&
 350         git merge --log c2 &&
 351         git show -s --pretty=tformat:%s%n%b >expect &&
 352
 353         test_config branch.master.mergeoptions "--log" &&
 354         git reset --hard c1 &&
 355         git merge c2 &&
 356         git show -s --pretty=tformat:%s%n%b >actual &&
 357
 358         test_cmp expect actual
 359 '
 360
 361 test_expect_success 'merge c1 with c2 (log in config gets overridden)' '
 362         git reset --hard c1 &&
 363         git merge c2 &&
 364         git show -s --pretty=tformat:%s%n%b >expect &&
 365
 366         test_config branch.master.mergeoptions "--no-log" &&
 367         test_config merge.log "true" &&
 368         git reset --hard c1 &&
 369         git merge c2 &&
 370         git show -s --pretty=tformat:%s%n%b >actual &&
 371
 372         test_cmp expect actual
 373 '
 374
 375 test_expect_success 'merge c1 with c2 (squash in config)' '
 376         git reset --hard c1 &&
 377         test_config branch.master.mergeoptions "--squash" &&
 378         git merge c2 &&
 379         verify_merge file result.1-5 &&
 380         verify_head $c1 &&
 381         verify_no_mergehead &&
 382         test_cmp squash.1-5 .git/SQUASH_MSG
 383 '
 384
 385 test_debug 'git log --graph --decorate --oneline --all'
 386
 387 test_expect_success 'override config option -n with --summary' '
 388         git reset --hard c1 &&
 389         test_config branch.master.mergeoptions "-n" &&
 390         test_tick &&
 391         git merge --summary c2 >diffstat.txt &&
 392         verify_merge file result.1-5 msg.1-5 &&
 393         verify_parents $c1 $c2 &&
 394         if ! grep "^ file |  *2 +-$" diffstat.txt
 395         then
 396                 echo "[OOPS] diffstat was not generated with --summary"
 397                 false
 398         fi
 399 '
 400
 401 test_expect_success 'override config option -n with --stat' '
 402         git reset --hard c1 &&
 403         test_config branch.master.mergeoptions "-n" &&
 404         test_tick &&
 405         git merge --stat c2 >diffstat.txt &&
 406         verify_merge file result.1-5 msg.1-5 &&
 407         verify_parents $c1 $c2 &&
 408         if ! grep "^ file |  *2 +-$" diffstat.txt
 409         then
 410                 echo "[OOPS] diffstat was not generated with --stat"
 411                 false
 412         fi
 413 '
 414
 415 test_debug 'git log --graph --decorate --oneline --all'
 416
 417 test_expect_success 'override config option --stat' '
 418         git reset --hard c1 &&
 419         test_config branch.master.mergeoptions "--stat" &&
 420         test_tick &&
 421         git merge -n c2 >diffstat.txt &&
 422         verify_merge file result.1-5 msg.1-5 &&
 423         verify_parents $c1 $c2 &&
 424         if grep "^ file |  *2 +-$" diffstat.txt
 425         then
 426                 echo "[OOPS] diffstat was generated"
 427                 false
 428         fi
 429 '
 430
 431 test_debug 'git log --graph --decorate --oneline --all'
 432
 433 test_expect_success 'merge c1 with c2 (override --no-commit)' '
 434         git reset --hard c1 &&
 435         test_config branch.master.mergeoptions "--no-commit" &&
 436         test_tick &&
 437         git merge --commit c2 &&
 438         verify_merge file result.1-5 msg.1-5 &&
 439         verify_parents $c1 $c2
 440 '
 441
 442 test_debug 'git log --graph --decorate --oneline --all'
 443
 444 test_expect_success 'merge c1 with c2 (override --squash)' '
 445         git reset --hard c1 &&
 446         test_config branch.master.mergeoptions "--squash" &&
 447         test_tick &&
 448         git merge --no-squash c2 &&
 449         verify_merge file result.1-5 msg.1-5 &&
 450         verify_parents $c1 $c2
 451 '
 452
 453 test_debug 'git log --graph --decorate --oneline --all'
 454
 455 test_expect_success 'merge c0 with c1 (no-ff)' '
 456         git reset --hard c0 &&
 457         test_tick &&
 458         git merge --no-ff c1 &&
 459         verify_merge file result.1 &&
 460         verify_parents $c0 $c1
 461 '
 462
 463 test_debug 'git log --graph --decorate --oneline --all'
 464
 465 test_expect_success 'merge c0 with c1 (merge.ff=false)' '
 466         git reset --hard c0 &&
 467         test_config merge.ff "false" &&
 468         test_tick &&
 469         git merge c1 &&
 470         verify_merge file result.1 &&
 471         verify_parents $c0 $c1
 472 '
 473 test_debug 'git log --graph --decorate --oneline --all'
 474
 475 test_expect_success 'combine branch.master.mergeoptions with merge.ff' '
 476         git reset --hard c0 &&
 477         test_config branch.master.mergeoptions "--ff" &&
 478         test_config merge.ff "false" &&
 479         test_tick &&
 480         git merge c1 &&
 481         verify_merge file result.1 &&
 482         verify_parents "$c0"
 483 '
 484
 485 test_expect_success 'tolerate unknown values for merge.ff' '
 486         git reset --hard c0 &&
 487         test_config merge.ff "something-new" &&
 488         test_tick &&
 489         git merge c1 2>message &&
 490         verify_head "$c1" &&
 491         test_cmp empty message
 492 '
 493
 494 test_expect_success 'combining --squash and --no-ff is refused' '
 495         git reset --hard c0 &&
 496         test_must_fail git merge --squash --no-ff c1 &&
 497         test_must_fail git merge --no-ff --squash c1
 498 '
 499
 500 test_expect_success 'combining --ff-only and --no-ff is refused' '
 501         test_must_fail git merge --ff-only --no-ff c1 &&
 502         test_must_fail git merge --no-ff --ff-only c1
 503 '
 504
 505 test_expect_success 'merge c0 with c1 (ff overrides no-ff)' '
 506         git reset --hard c0 &&
 507         test_config branch.master.mergeoptions "--no-ff" &&
 508         git merge --ff c1 &&
 509         verify_merge file result.1 &&
 510         verify_head $c1
 511 '
 512
 513 test_expect_success 'merge log message' '
 514         git reset --hard c0 &&
 515         git merge --no-log c2 &&
 516         git show -s --pretty=format:%b HEAD >msg.act &&
 517         test_cmp msg.nologff msg.act &&
 518
 519         git reset --hard c0 &&
 520         test_config branch.master.mergeoptions "--no-ff" &&
 521         git merge --no-log c2 &&
 522         git show -s --pretty=format:%b HEAD >msg.act &&
 523         test_cmp msg.nolognoff msg.act &&
 524
 525         git merge --log c3 &&
 526         git show -s --pretty=format:%b HEAD >msg.act &&
 527         test_cmp msg.log msg.act &&
 528
 529         git reset --hard HEAD^ &&
 530         test_config merge.log "yes" &&
 531         git merge c3 &&
 532         git show -s --pretty=format:%b HEAD >msg.act &&
 533         test_cmp msg.log msg.act
 534 '
 535
 536 test_debug 'git log --graph --decorate --oneline --all'
 537
 538 test_expect_success 'merge c1 with c0, c2, c0, and c1' '
 539        git reset --hard c1 &&
 540        test_tick &&
 541        git merge c0 c2 c0 c1 &&
 542        verify_merge file result.1-5 &&
 543        verify_parents $c1 $c2
 544 '
 545
 546 test_debug 'git log --graph --decorate --oneline --all'
 547
 548 test_expect_success 'merge c1 with c0, c2, c0, and c1' '
 549        git reset --hard c1 &&
 550        test_tick &&
 551        git merge c0 c2 c0 c1 &&
 552        verify_merge file result.1-5 &&
 553        verify_parents $c1 $c2
 554 '
 555
 556 test_debug 'git log --graph --decorate --oneline --all'
 557
 558 test_expect_success 'merge c1 with c1 and c2' '
 559        git reset --hard c1 &&
 560        test_tick &&
 561        git merge c1 c2 &&
 562        verify_merge file result.1-5 &&
 563        verify_parents $c1 $c2
 564 '
 565
 566 test_debug 'git log --graph --decorate --oneline --all'
 567
 568 test_expect_success 'merge fast-forward in a dirty tree' '
 569        git reset --hard c0 &&
 570        mv file file1 &&
 571        cat file1 >file &&
 572        rm -f file1 &&
 573        git merge c2
 574 '
 575
 576 test_debug 'git log --graph --decorate --oneline --all'
 577
 578 test_expect_success 'in-index merge' '
 579         git reset --hard c0 &&
 580         git merge --no-ff -s resolve c1 >out &&
 581         test_i18ngrep "Wonderful." out &&
 582         verify_parents $c0 $c1
 583 '
 584
 585 test_debug 'git log --graph --decorate --oneline --all'
 586
 587 test_expect_success 'refresh the index before merging' '
 588         git reset --hard c1 &&
 589         cp file file.n && mv -f file.n file &&
 590         git merge c3
 591 '
 592
 593 cat >expected.branch <<\EOF
 594 Merge branch 'c5-branch' (early part)
 595 EOF
 596 cat >expected.tag <<\EOF
 597 Merge commit 'c5~1'
 598 EOF
 599
 600 test_expect_success 'merge early part of c2' '
 601         git reset --hard c3 &&
 602         echo c4 >c4.c &&
 603         git add c4.c &&
 604         git commit -m c4 &&
 605         git tag c4 &&
 606         echo c5 >c5.c &&
 607         git add c5.c &&
 608         git commit -m c5 &&
 609         git tag c5 &&
 610         git reset --hard c3 &&
 611         echo c6 >c6.c &&
 612         git add c6.c &&
 613         git commit -m c6 &&
 614         git tag c6 &&
 615         git branch -f c5-branch c5 &&
 616         git merge c5-branch~1 &&
 617         git show -s --pretty=format:%s HEAD >actual.branch &&
 618         git reset --keep HEAD^ &&
 619         git merge c5~1 &&
 620         git show -s --pretty=format:%s HEAD >actual.tag &&
 621         test_cmp expected.branch actual.branch &&
 622         test_cmp expected.tag actual.tag
 623 '
 624
 625 test_debug 'git log --graph --decorate --oneline --all'
 626
 627 test_expect_success 'merge --no-ff --no-commit && commit' '
 628         git reset --hard c0 &&
 629         git merge --no-ff --no-commit c1 &&
 630         EDITOR=: git commit &&
 631         verify_parents $c0 $c1
 632 '
 633
 634 test_debug 'git log --graph --decorate --oneline --all'
 635
 636 test_expect_success 'amending no-ff merge commit' '
 637         EDITOR=: git commit --amend &&
 638         verify_parents $c0 $c1
 639 '
 640
 641 test_debug 'git log --graph --decorate --oneline --all'
 642
 643 cat >editor <<\EOF
 644 #!/bin/sh
 645 # Add a new message string that was not in the template
 646 (
 647         echo "Merge work done on the side branch c1"
 648         echo
 649         cat <"$1"
 650 ) >"$1.tmp" && mv "$1.tmp" "$1"
 651 # strip comments and blank lines from end of message
 652 sed -e '/^#/d' < "$1" | sed -e :a -e '/^\n*$/{$d;N;ba' -e '}' > expected
 653 EOF
 654 chmod 755 editor
 655
 656 test_expect_success 'merge --no-ff --edit' '
 657         git reset --hard c0 &&
 658         EDITOR=./editor git merge --no-ff --edit c1 &&
 659         verify_parents $c0 $c1 &&
 660         git cat-file commit HEAD >raw &&
 661         grep "work done on the side branch" raw &&
 662         sed "1,/^$/d" >actual raw &&
 663         test_cmp actual expected
 664 '
 665
 666 test_expect_success GPG 'merge --ff-only tag' '
 667         git reset --hard c0 &&
 668         git commit --allow-empty -m "A newer commit" &&
 669         git tag -s -m "A newer commit" signed &&
 670         git reset --hard c0 &&
 671
 672         git merge --ff-only signed &&
 673         git rev-parse signed^0 >expect &&
 674         git rev-parse HEAD >actual &&
 675         test_cmp actual expect
 676 '
 677
 678 test_expect_success GPG 'merge --no-edit tag should skip editor' '
 679         git reset --hard c0 &&
 680         git commit --allow-empty -m "A newer commit" &&
 681         git tag -f -s -m "A newer commit" signed &&
 682         git reset --hard c0 &&
 683
 684         EDITOR=false git merge --no-edit signed &&
 685         git rev-parse signed^0 >expect &&
 686         git rev-parse HEAD^2 >actual &&
 687         test_cmp actual expect
 688 '
 689
 690 test_done