t/t5616-partial-clone.sh

   1 #!/bin/sh
   2
   3 test_description='git partial clone'
   4
   5 . ./test-lib.sh
   6
   7 # create a normal "src" repo where we can later create new commits.
   8 # expect_1.oids will contain a list of the OIDs of all blobs.
   9 test_expect_success 'setup normal src repo' '
  10         echo "{print \$1}" >print_1.awk &&
  11         echo "{print \$2}" >print_2.awk &&
  12
  13         git init src &&
  14         for n in 1 2 3 4
  15         do
  16                 echo "This is file: $n" > src/file.$n.txt
  17                 git -C src add file.$n.txt
  18                 git -C src commit -m "file $n"
  19                 git -C src ls-files -s file.$n.txt >>temp
  20         done &&
  21         awk -f print_2.awk <temp | sort >expect_1.oids &&
  22         test_line_count = 4 expect_1.oids
  23 '
  24
  25 # bare clone "src" giving "srv.bare" for use as our server.
  26 test_expect_success 'setup bare clone for server' '
  27         git clone --bare "file://$(pwd)/src" srv.bare &&
  28         git -C srv.bare config --local uploadpack.allowfilter 1 &&
  29         git -C srv.bare config --local uploadpack.allowanysha1inwant 1
  30 '
  31
  32 # do basic partial clone from "srv.bare"
  33 # confirm we are missing all of the known blobs.
  34 # confirm partial clone was registered in the local config.
  35 test_expect_success 'do partial clone 1' '
  36         git clone --no-checkout --filter=blob:none "file://$(pwd)/srv.bare" pc1 &&
  37
  38         git -C pc1 rev-list --quiet --objects --missing=print HEAD >revs &&
  39         awk -f print_1.awk revs |
  40         sed "s/?//" |
  41         sort >observed.oids &&
  42
  43         test_cmp expect_1.oids observed.oids &&
  44         test "$(git -C pc1 config --local core.repositoryformatversion)" = "1" &&
  45         test "$(git -C pc1 config --local remote.origin.promisor)" = "true" &&
  46         test "$(git -C pc1 config --local remote.origin.partialclonefilter)" = "blob:none"
  47 '
  48
  49 test_expect_success 'verify that .promisor file contains refs fetched' '
  50         ls pc1/.git/objects/pack/pack-*.promisor >promisorlist &&
  51         test_line_count = 1 promisorlist &&
  52         git -C srv.bare rev-parse --verify HEAD >headhash &&
  53         grep "$(cat headhash) HEAD" $(cat promisorlist) &&
  54         grep "$(cat headhash) refs/heads/master" $(cat promisorlist)
  55 '
  56
  57 # checkout master to force dynamic object fetch of blobs at HEAD.
  58 test_expect_success 'verify checkout with dynamic object fetch' '
  59         git -C pc1 rev-list --quiet --objects --missing=print HEAD >observed &&
  60         test_line_count = 4 observed &&
  61         git -C pc1 checkout master &&
  62         git -C pc1 rev-list --quiet --objects --missing=print HEAD >observed &&
  63         test_line_count = 0 observed
  64 '
  65
  66 # create new commits in "src" repo to establish a blame history on file.1.txt
  67 # and push to "srv.bare".
  68 test_expect_success 'push new commits to server' '
  69         git -C src remote add srv "file://$(pwd)/srv.bare" &&
  70         for x in a b c d e
  71         do
  72                 echo "Mod file.1.txt $x" >>src/file.1.txt
  73                 git -C src add file.1.txt
  74                 git -C src commit -m "mod $x"
  75         done &&
  76         git -C src blame master -- file.1.txt >expect.blame &&
  77         git -C src push -u srv master
  78 '
  79
  80 # (partial) fetch in the partial clone repo from the promisor remote.
  81 # verify that fetch inherited the filter-spec from the config and DOES NOT
  82 # have the new blobs.
  83 test_expect_success 'partial fetch inherits filter settings' '
  84         git -C pc1 fetch origin &&
  85         git -C pc1 rev-list --quiet --objects --missing=print \
  86                 master..origin/master >observed &&
  87         test_line_count = 5 observed
  88 '
  89
  90 # force dynamic object fetch using diff.
  91 # we should only get 1 new blob (for the file in origin/master).
  92 test_expect_success 'verify diff causes dynamic object fetch' '
  93         git -C pc1 diff master..origin/master -- file.1.txt &&
  94         git -C pc1 rev-list --quiet --objects --missing=print \
  95                  master..origin/master >observed &&
  96         test_line_count = 4 observed
  97 '
  98
  99 # force full dynamic object fetch of the file's history using blame.
 100 # we should get the intermediate blobs for the file.
 101 test_expect_success 'verify blame causes dynamic object fetch' '
 102         git -C pc1 blame origin/master -- file.1.txt >observed.blame &&
 103         test_cmp expect.blame observed.blame &&
 104         git -C pc1 rev-list --quiet --objects --missing=print \
 105                 master..origin/master >observed &&
 106         test_line_count = 0 observed
 107 '
 108
 109 # create new commits in "src" repo to establish a history on file.2.txt
 110 # and push to "srv.bare".
 111 test_expect_success 'push new commits to server for file.2.txt' '
 112         for x in a b c d e f
 113         do
 114                 echo "Mod file.2.txt $x" >>src/file.2.txt
 115                 git -C src add file.2.txt
 116                 git -C src commit -m "mod $x"
 117         done &&
 118         git -C src push -u srv master
 119 '
 120
 121 # Do FULL fetch by disabling inherited filter-spec using --no-filter.
 122 # Verify we have all the new blobs.
 123 test_expect_success 'override inherited filter-spec using --no-filter' '
 124         git -C pc1 fetch --no-filter origin &&
 125         git -C pc1 rev-list --quiet --objects --missing=print \
 126                 master..origin/master >observed &&
 127         test_line_count = 0 observed
 128 '
 129
 130 # create new commits in "src" repo to establish a history on file.3.txt
 131 # and push to "srv.bare".
 132 test_expect_success 'push new commits to server for file.3.txt' '
 133         for x in a b c d e f
 134         do
 135                 echo "Mod file.3.txt $x" >>src/file.3.txt
 136                 git -C src add file.3.txt
 137                 git -C src commit -m "mod $x"
 138         done &&
 139         git -C src push -u srv master
 140 '
 141
 142 # Do a partial fetch and then try to manually fetch the missing objects.
 143 # This can be used as the basis of a pre-command hook to bulk fetch objects
 144 # perhaps combined with a command in dry-run mode.
 145 test_expect_success 'manual prefetch of missing objects' '
 146         git -C pc1 fetch --filter=blob:none origin &&
 147
 148         git -C pc1 rev-list --quiet --objects --missing=print \
 149                  master..origin/master >revs &&
 150         awk -f print_1.awk revs |
 151         sed "s/?//" |
 152         sort >observed.oids &&
 153
 154         test_line_count = 6 observed.oids &&
 155         git -C pc1 fetch-pack --stdin "file://$(pwd)/srv.bare" <observed.oids &&
 156
 157         git -C pc1 rev-list --quiet --objects --missing=print \
 158                 master..origin/master >revs &&
 159         awk -f print_1.awk revs |
 160         sed "s/?//" |
 161         sort >observed.oids &&
 162
 163         test_line_count = 0 observed.oids
 164 '
 165
 166 test_expect_success 'partial clone with transfer.fsckobjects=1 uses index-pack --fsck-objects' '
 167         git init src &&
 168         test_commit -C src x &&
 169         test_config -C src uploadpack.allowfilter 1 &&
 170         test_config -C src uploadpack.allowanysha1inwant 1 &&
 171
 172         GIT_TRACE="$(pwd)/trace" git -c transfer.fsckobjects=1 \
 173                 clone --filter="blob:none" "file://$(pwd)/src" dst &&
 174         grep "git index-pack.*--fsck-objects" trace
 175 '
 176
 177 test_expect_success 'use fsck before and after manually fetching a missing subtree' '
 178         # push new commit so server has a subtree
 179         mkdir src/dir &&
 180         echo "in dir" >src/dir/file.txt &&
 181         git -C src add dir/file.txt &&
 182         git -C src commit -m "file in dir" &&
 183         git -C src push -u srv master &&
 184         SUBTREE=$(git -C src rev-parse HEAD:dir) &&
 185
 186         rm -rf dst &&
 187         git clone --no-checkout --filter=tree:0 "file://$(pwd)/srv.bare" dst &&
 188         git -C dst fsck &&
 189
 190         # Make sure we only have commits, and all trees and blobs are missing.
 191         git -C dst rev-list --missing=allow-any --objects master \
 192                 >fetched_objects &&
 193         awk -f print_1.awk fetched_objects |
 194         xargs -n1 git -C dst cat-file -t >fetched_types &&
 195
 196         sort -u fetched_types >unique_types.observed &&
 197         echo commit >unique_types.expected &&
 198         test_cmp unique_types.expected unique_types.observed &&
 199
 200         # Auto-fetch a tree with cat-file.
 201         git -C dst cat-file -p $SUBTREE >tree_contents &&
 202         grep file.txt tree_contents &&
 203
 204         # fsck still works after an auto-fetch of a tree.
 205         git -C dst fsck &&
 206
 207         # Auto-fetch all remaining trees and blobs with --missing=error
 208         git -C dst rev-list --missing=error --objects master >fetched_objects &&
 209         test_line_count = 70 fetched_objects &&
 210
 211         awk -f print_1.awk fetched_objects |
 212         xargs -n1 git -C dst cat-file -t >fetched_types &&
 213
 214         sort -u fetched_types >unique_types.observed &&
 215         test_write_lines blob commit tree >unique_types.expected &&
 216         test_cmp unique_types.expected unique_types.observed
 217 '
 218
 219 test_expect_success 'implicitly construct combine: filter with repeated flags' '
 220         GIT_TRACE=$(pwd)/trace git clone --bare \
 221                 --filter=blob:none --filter=tree:1 \
 222                 "file://$(pwd)/srv.bare" pc2 &&
 223         grep "trace:.* git pack-objects .*--filter=combine:blob:none+tree:1" \
 224                 trace &&
 225         git -C pc2 rev-list --objects --missing=allow-any HEAD >objects &&
 226
 227         # We should have gotten some root trees.
 228         grep " $" objects &&
 229         # Should not have gotten any non-root trees or blobs.
 230         ! grep " ." objects &&
 231
 232         xargs -n 1 git -C pc2 cat-file -t <objects >types &&
 233         sort -u types >unique_types.actual &&
 234         test_write_lines commit tree >unique_types.expected &&
 235         test_cmp unique_types.expected unique_types.actual
 236 '
 237
 238 test_expect_success 'partial clone fetches blobs pointed to by refs even if normally filtered out' '
 239         rm -rf src dst &&
 240         git init src &&
 241         test_commit -C src x &&
 242         test_config -C src uploadpack.allowfilter 1 &&
 243         test_config -C src uploadpack.allowanysha1inwant 1 &&
 244
 245         # Create a tag pointing to a blob.
 246         BLOB=$(echo blob-contents | git -C src hash-object --stdin -w) &&
 247         git -C src tag myblob "$BLOB" &&
 248
 249         git clone --filter="blob:none" "file://$(pwd)/src" dst 2>err &&
 250         ! grep "does not point to a valid object" err &&
 251         git -C dst fsck
 252 '
 253
 254 test_expect_success 'fetch what is specified on CLI even if already promised' '
 255         rm -rf src dst.git &&
 256         git init src &&
 257         test_commit -C src foo &&
 258         test_config -C src uploadpack.allowfilter 1 &&
 259         test_config -C src uploadpack.allowanysha1inwant 1 &&
 260
 261         git hash-object --stdin <src/foo.t >blob &&
 262
 263         git clone --bare --filter=blob:none "file://$(pwd)/src" dst.git &&
 264         git -C dst.git rev-list --objects --quiet --missing=print HEAD >missing_before &&
 265         grep "?$(cat blob)" missing_before &&
 266         git -C dst.git fetch origin $(cat blob) &&
 267         git -C dst.git rev-list --objects --quiet --missing=print HEAD >missing_after &&
 268         ! grep "?$(cat blob)" missing_after
 269 '
 270
 271 test_expect_success 'setup src repo for sparse filter' '
 272         git init sparse-src &&
 273         git -C sparse-src config --local uploadpack.allowfilter 1 &&
 274         git -C sparse-src config --local uploadpack.allowanysha1inwant 1 &&
 275         test_commit -C sparse-src one &&
 276         test_commit -C sparse-src two &&
 277         echo /one.t >sparse-src/only-one &&
 278         git -C sparse-src add . &&
 279         git -C sparse-src commit -m "add sparse checkout files"
 280 '
 281
 282 test_expect_success 'partial clone with sparse filter succeeds' '
 283         rm -rf dst.git &&
 284         git clone --no-local --bare \
 285                   --filter=sparse:oid=master:only-one \
 286                   sparse-src dst.git &&
 287         (
 288                 cd dst.git &&
 289                 git rev-list --objects --missing=print HEAD >out &&
 290                 grep "^$(git rev-parse HEAD:one.t)" out &&
 291                 grep "^?$(git rev-parse HEAD:two.t)" out
 292         )
 293 '
 294
 295 test_expect_success 'partial clone with unresolvable sparse filter fails cleanly' '
 296         rm -rf dst.git &&
 297         test_must_fail git clone --no-local --bare \
 298                                  --filter=sparse:oid=master:no-such-name \
 299                                  sparse-src dst.git 2>err &&
 300         test_i18ngrep "unable to access sparse blob in .master:no-such-name" err &&
 301         test_must_fail git clone --no-local --bare \
 302                                  --filter=sparse:oid=master \
 303                                  sparse-src dst.git 2>err &&
 304         test_i18ngrep "unable to parse sparse filter data in" err
 305 '
 306
 307 setup_triangle () {
 308         rm -rf big-blob.txt server client promisor-remote &&
 309
 310         printf "line %d\n" $(test_seq 1 100) >big-blob.txt &&
 311
 312         # Create a server with 2 commits: a commit with a big tree and a child
 313         # commit with an incremental change. Also, create a partial clone
 314         # client that only contains the first commit.
 315         git init server &&
 316         git -C server config --local uploadpack.allowfilter 1 &&
 317         for i in $(test_seq 1 100)
 318         do
 319                 echo "make the tree big" >server/file$i &&
 320                 git -C server add file$i
 321         done &&
 322         git -C server commit -m "initial" &&
 323         git clone --bare --filter=tree:0 "file://$(pwd)/server" client &&
 324         echo another line >>server/file1 &&
 325         git -C server commit -am "incremental change" &&
 326
 327         # Create a promisor remote that only contains the tree and blob from
 328         # the first commit.
 329         git init promisor-remote &&
 330         git -C server config --local uploadpack.allowanysha1inwant 1 &&
 331         TREE_HASH=$(git -C server rev-parse HEAD~1^{tree}) &&
 332         git -C promisor-remote fetch --keep "file://$(pwd)/server" "$TREE_HASH" &&
 333         git -C promisor-remote count-objects -v >object-count &&
 334         test_i18ngrep "count: 0" object-count &&
 335         test_i18ngrep "in-pack: 2" object-count &&
 336
 337         # Set it as the promisor remote of client. Thus, whenever
 338         # the client lazy fetches, the lazy fetch will succeed only if it is
 339         # for this tree or blob.
 340         test_commit -C promisor-remote one && # so that ref advertisement is not empty
 341         git -C promisor-remote config --local uploadpack.allowanysha1inwant 1 &&
 342         git -C client remote set-url origin "file://$(pwd)/promisor-remote"
 343 }
 344
 345 # NEEDSWORK: The tests beginning with "fetch lazy-fetches" below only
 346 # test that "fetch" avoid fetching trees and blobs, but not commits or
 347 # tags. Revisit this if Git is ever taught to support partial clones
 348 # with commits and/or tags filtered out.
 349
 350 test_expect_success 'fetch lazy-fetches only to resolve deltas' '
 351         setup_triangle &&
 352
 353         # Exercise to make sure it works. Git will not fetch anything from the
 354         # promisor remote other than for the big tree (because it needs to
 355         # resolve the delta).
 356         GIT_TRACE_PACKET="$(pwd)/trace" git -C client \
 357                 fetch "file://$(pwd)/server" master &&
 358
 359         # Verify the assumption that the client needed to fetch the delta base
 360         # to resolve the delta.
 361         git -C server rev-parse HEAD~1^{tree} >hash &&
 362         grep "want $(cat hash)" trace
 363 '
 364
 365 test_expect_success 'fetch lazy-fetches only to resolve deltas, protocol v2' '
 366         setup_triangle &&
 367
 368         git -C server config --local protocol.version 2 &&
 369         git -C client config --local protocol.version 2 &&
 370         git -C promisor-remote config --local protocol.version 2 &&
 371
 372         # Exercise to make sure it works. Git will not fetch anything from the
 373         # promisor remote other than for the big blob (because it needs to
 374         # resolve the delta).
 375         GIT_TRACE_PACKET="$(pwd)/trace" git -C client \
 376                 fetch "file://$(pwd)/server" master &&
 377
 378         # Verify that protocol version 2 was used.
 379         grep "fetch< version 2" trace &&
 380
 381         # Verify the assumption that the client needed to fetch the delta base
 382         # to resolve the delta.
 383         git -C server rev-parse HEAD~1^{tree} >hash &&
 384         grep "want $(cat hash)" trace
 385 '
 386
 387 # The following two tests must be in this order, or else
 388 # the first will not fail. It is important that the srv.bare
 389 # repository did not have tags during clone, but has tags
 390 # in the fetch.
 391
 392 test_expect_failure 'verify fetch succeeds when asking for new tags' '
 393         git clone --filter=blob:none "file://$(pwd)/srv.bare" tag-test &&
 394         for i in I J K
 395         do
 396                 test_commit -C src $i &&
 397                 git -C src branch $i || return 1
 398         done &&
 399         git -C srv.bare fetch --tags origin +refs/heads/*:refs/heads/* &&
 400         git -C tag-test -c protocol.version=2 fetch --tags origin
 401 '
 402
 403 test_expect_success 'verify fetch downloads only one pack when updating refs' '
 404         git clone --filter=blob:none "file://$(pwd)/srv.bare" pack-test &&
 405         ls pack-test/.git/objects/pack/*pack >pack-list &&
 406         test_line_count = 2 pack-list &&
 407         for i in A B C
 408         do
 409                 test_commit -C src $i &&
 410                 git -C src branch $i || return 1
 411         done &&
 412         git -C srv.bare fetch origin +refs/heads/*:refs/heads/* &&
 413         git -C pack-test fetch origin &&
 414         ls pack-test/.git/objects/pack/*pack >pack-list &&
 415         test_line_count = 3 pack-list
 416 '
 417
 418 test_expect_success 'single-branch tag following respects partial clone' '
 419         git clone --single-branch -b B --filter=blob:none \
 420                 "file://$(pwd)/srv.bare" single &&
 421         git -C single rev-parse --verify refs/tags/B &&
 422         git -C single rev-parse --verify refs/tags/A &&
 423         test_must_fail git -C single rev-parse --verify refs/tags/C
 424 '
 425
 426 . "$TEST_DIRECTORY"/lib-httpd.sh
 427 start_httpd
 428
 429 # Converts bytes into their hexadecimal representation. For example,
 430 # "printf 'ab\r\n' | hex_unpack" results in '61620d0a'.
 431 hex_unpack () {
 432         perl -e '$/ = undef; $input = <>; print unpack("H2" x length($input), $input)'
 433 }
 434
 435 # Inserts $1 at the start of the string and every 2 characters thereafter.
 436 intersperse () {
 437         sed 's/\(..\)/'$1'\1/g'
 438 }
 439
 440 # Create a one-time-perl command to replace the existing packfile with $1.
 441 replace_packfile () {
 442         # The protocol requires that the packfile be sent in sideband 1, hence
 443         # the extra \x01 byte at the beginning.
 444         cp $1 "$HTTPD_ROOT_PATH/one-time-pack" &&
 445         echo 'if (/packfile/) {
 446                 print;
 447                 my $length = -s "one-time-pack";
 448                 printf "%04x\x01", $length + 5;
 449                 print `cat one-time-pack` . "0000";
 450                 last
 451         }' >"$HTTPD_ROOT_PATH/one-time-perl"
 452 }
 453
 454 test_expect_success 'upon cloning, check that all refs point to objects' '
 455         SERVER="$HTTPD_DOCUMENT_ROOT_PATH/server" &&
 456         rm -rf "$SERVER" repo &&
 457         test_create_repo "$SERVER" &&
 458         test_commit -C "$SERVER" foo &&
 459         test_config -C "$SERVER" uploadpack.allowfilter 1 &&
 460         test_config -C "$SERVER" uploadpack.allowanysha1inwant 1 &&
 461
 462         # Create a tag pointing to a blob.
 463         BLOB=$(echo blob-contents | git -C "$SERVER" hash-object --stdin -w) &&
 464         git -C "$SERVER" tag myblob "$BLOB" &&
 465
 466         # Craft a packfile not including that blob.
 467         git -C "$SERVER" rev-parse HEAD |
 468         git -C "$SERVER" pack-objects --stdout >incomplete.pack &&
 469
 470         # Replace the existing packfile with the crafted one. The protocol
 471         # requires that the packfile be sent in sideband 1, hence the extra
 472         # \x01 byte at the beginning.
 473         replace_packfile incomplete.pack &&
 474
 475         # Use protocol v2 because the perl command looks for the "packfile"
 476         # section header.
 477         test_config -C "$SERVER" protocol.version 2 &&
 478         test_must_fail git -c protocol.version=2 clone \
 479                 --filter=blob:none $HTTPD_URL/one_time_perl/server repo 2>err &&
 480
 481         test_i18ngrep "did not send all necessary objects" err &&
 482
 483         # Ensure that the one-time-perl script was used.
 484         ! test -e "$HTTPD_ROOT_PATH/one-time-perl"
 485 '
 486
 487 test_expect_success 'when partial cloning, tolerate server not sending target of tag' '
 488         SERVER="$HTTPD_DOCUMENT_ROOT_PATH/server" &&
 489         rm -rf "$SERVER" repo &&
 490         test_create_repo "$SERVER" &&
 491         test_commit -C "$SERVER" foo &&
 492         test_config -C "$SERVER" uploadpack.allowfilter 1 &&
 493         test_config -C "$SERVER" uploadpack.allowanysha1inwant 1 &&
 494
 495         # Create an annotated tag pointing to a blob.
 496         BLOB=$(echo blob-contents | git -C "$SERVER" hash-object --stdin -w) &&
 497         git -C "$SERVER" tag -m message -a myblob "$BLOB" &&
 498
 499         # Craft a packfile including the tag, but not the blob it points to.
 500         # Also, omit objects referenced from HEAD in order to force a second
 501         # fetch (to fetch missing objects) upon the automatic checkout that
 502         # happens after a clone.
 503         printf "%s\n%s\n--not\n%s\n%s\n" \
 504                 $(git -C "$SERVER" rev-parse HEAD) \
 505                 $(git -C "$SERVER" rev-parse myblob) \
 506                 $(git -C "$SERVER" rev-parse HEAD^{tree}) \
 507                 $(git -C "$SERVER" rev-parse myblob^{blob}) |
 508                 git -C "$SERVER" pack-objects --thin --stdout >incomplete.pack &&
 509
 510         # Replace the existing packfile with the crafted one. The protocol
 511         # requires that the packfile be sent in sideband 1, hence the extra
 512         # \x01 byte at the beginning.
 513         replace_packfile incomplete.pack &&
 514
 515         # Use protocol v2 because the perl command looks for the "packfile"
 516         # section header.
 517         test_config -C "$SERVER" protocol.version 2 &&
 518
 519         # Exercise to make sure it works.
 520         git -c protocol.version=2 clone \
 521                 --filter=blob:none $HTTPD_URL/one_time_perl/server repo 2> err &&
 522         ! grep "missing object referenced by" err &&
 523
 524         # Ensure that the one-time-perl script was used.
 525         ! test -e "$HTTPD_ROOT_PATH/one-time-perl"
 526 '
 527
 528 test_expect_success 'tolerate server sending REF_DELTA against missing promisor objects' '
 529         SERVER="$HTTPD_DOCUMENT_ROOT_PATH/server" &&
 530         rm -rf "$SERVER" repo &&
 531         test_create_repo "$SERVER" &&
 532         test_config -C "$SERVER" uploadpack.allowfilter 1 &&
 533         test_config -C "$SERVER" uploadpack.allowanysha1inwant 1 &&
 534
 535         # Create a commit with 2 blobs to be used as delta bases.
 536         for i in $(test_seq 10)
 537         do
 538                 echo "this is a line" >>"$SERVER/foo.txt" &&
 539                 echo "this is another line" >>"$SERVER/have.txt"
 540         done &&
 541         git -C "$SERVER" add foo.txt have.txt &&
 542         git -C "$SERVER" commit -m bar &&
 543         git -C "$SERVER" rev-parse HEAD:foo.txt >deltabase_missing &&
 544         git -C "$SERVER" rev-parse HEAD:have.txt >deltabase_have &&
 545
 546         # Clone. The client has deltabase_have but not deltabase_missing.
 547         git -c protocol.version=2 clone --no-checkout \
 548                 --filter=blob:none $HTTPD_URL/one_time_perl/server repo &&
 549         git -C repo hash-object -w -- "$SERVER/have.txt" &&
 550
 551         # Sanity check to ensure that the client does not have
 552         # deltabase_missing.
 553         git -C repo rev-list --objects --ignore-missing \
 554                 -- $(cat deltabase_missing) >objlist &&
 555         test_line_count = 0 objlist &&
 556
 557         # Another commit. This commit will be fetched by the client.
 558         echo "abcdefghijklmnopqrstuvwxyz" >>"$SERVER/foo.txt" &&
 559         echo "abcdefghijklmnopqrstuvwxyz" >>"$SERVER/have.txt" &&
 560         git -C "$SERVER" add foo.txt have.txt &&
 561         git -C "$SERVER" commit -m baz &&
 562
 563         # Pack a thin pack containing, among other things, HEAD:foo.txt
 564         # delta-ed against HEAD^:foo.txt and HEAD:have.txt delta-ed against
 565         # HEAD^:have.txt.
 566         printf "%s\n--not\n%s\n" \
 567                 $(git -C "$SERVER" rev-parse HEAD) \
 568                 $(git -C "$SERVER" rev-parse HEAD^) |
 569                 git -C "$SERVER" pack-objects --thin --stdout >thin.pack &&
 570
 571         # Ensure that the pack contains one delta against HEAD^:foo.txt. Since
 572         # the delta contains at least 26 novel characters, the size cannot be
 573         # contained in 4 bits, so the object header will take up 2 bytes. The
 574         # most significant nybble of the first byte is 0b1111 (0b1 to indicate
 575         # that the header continues, and 0b111 to indicate REF_DELTA), followed
 576         # by any 3 nybbles, then the OID of the delta base.
 577         printf "f.,..%s" $(intersperse "," <deltabase_missing) >want &&
 578         hex_unpack <thin.pack | intersperse "," >have &&
 579         grep $(cat want) have &&
 580
 581         # Ensure that the pack contains one delta against HEAD^:have.txt,
 582         # similar to the above.
 583         printf "f.,..%s" $(intersperse "," <deltabase_have) >want &&
 584         hex_unpack <thin.pack | intersperse "," >have &&
 585         grep $(cat want) have &&
 586
 587         replace_packfile thin.pack &&
 588
 589         # Use protocol v2 because the perl command looks for the "packfile"
 590         # section header.
 591         test_config -C "$SERVER" protocol.version 2 &&
 592
 593         # Fetch the thin pack and ensure that index-pack is able to handle the
 594         # REF_DELTA object with a missing promisor delta base.
 595         GIT_TRACE_PACKET="$(pwd)/trace" git -C repo -c protocol.version=2 fetch &&
 596
 597         # Ensure that the missing delta base was directly fetched, but not the
 598         # one that the client has.
 599         grep "want $(cat deltabase_missing)" trace &&
 600         ! grep "want $(cat deltabase_have)" trace &&
 601
 602         # Ensure that the one-time-perl script was used.
 603         ! test -e "$HTTPD_ROOT_PATH/one-time-perl"
 604 '
 605
 606 # DO NOT add non-httpd-specific tests here, because the last part of this
 607 # test script is only executed when httpd is available and enabled.
 608
 609 test_done