t/test-lib-functions.sh

   1 # Library of functions shared by all tests scripts, included by
   2 # test-lib.sh.
   3 #
   4 # Copyright (c) 2005 Junio C Hamano
   5 #
   6 # This program is free software: you can redistribute it and/or modify
   7 # it under the terms of the GNU General Public License as published by
   8 # the Free Software Foundation, either version 2 of the License, or
   9 # (at your option) any later version.
  10 #
  11 # This program is distributed in the hope that it will be useful,
  12 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 # GNU General Public License for more details.
  15 #
  16 # You should have received a copy of the GNU General Public License
  17 # along with this program.  If not, see http://www.gnu.org/licenses/ .
  18
  19 # The semantics of the editor variables are that of invoking
  20 # sh -c "$EDITOR \"$@\"" files ...
  21 #
  22 # If our trash directory contains shell metacharacters, they will be
  23 # interpreted if we just set $EDITOR directly, so do a little dance with
  24 # environment variables to work around this.
  25 #
  26 # In particular, quoting isn't enough, as the path may contain the same quote
  27 # that we're using.
  28 test_set_editor () {
  29         FAKE_EDITOR="$1"
  30         export FAKE_EDITOR
  31         EDITOR='"$FAKE_EDITOR"'
  32         export EDITOR
  33 }
  34
  35 test_set_index_version () {
  36     GIT_INDEX_VERSION="$1"
  37     export GIT_INDEX_VERSION
  38 }
  39
  40 test_decode_color () {
  41         awk '
  42                 function name(n) {
  43                         if (n == 0) return "RESET";
  44                         if (n == 1) return "BOLD";
  45                         if (n == 30) return "BLACK";
  46                         if (n == 31) return "RED";
  47                         if (n == 32) return "GREEN";
  48                         if (n == 33) return "YELLOW";
  49                         if (n == 34) return "BLUE";
  50                         if (n == 35) return "MAGENTA";
  51                         if (n == 36) return "CYAN";
  52                         if (n == 37) return "WHITE";
  53                         if (n == 40) return "BLACK";
  54                         if (n == 41) return "BRED";
  55                         if (n == 42) return "BGREEN";
  56                         if (n == 43) return "BYELLOW";
  57                         if (n == 44) return "BBLUE";
  58                         if (n == 45) return "BMAGENTA";
  59                         if (n == 46) return "BCYAN";
  60                         if (n == 47) return "BWHITE";
  61                 }
  62                 {
  63                         while (match($0, /\033\[[0-9;]*m/) != 0) {
  64                                 printf "%s<", substr($0, 1, RSTART-1);
  65                                 codes = substr($0, RSTART+2, RLENGTH-3);
  66                                 if (length(codes) == 0)
  67                                         printf "%s", name(0)
  68                                 else {
  69                                         n = split(codes, ary, ";");
  70                                         sep = "";
  71                                         for (i = 1; i <= n; i++) {
  72                                                 printf "%s%s", sep, name(ary[i]);
  73                                                 sep = ";"
  74                                         }
  75                                 }
  76                                 printf ">";
  77                                 $0 = substr($0, RSTART + RLENGTH, length($0) - RSTART - RLENGTH + 1);
  78                         }
  79                         print
  80                 }
  81         '
  82 }
  83
  84 lf_to_nul () {
  85         perl -pe 'y/\012/\000/'
  86 }
  87
  88 nul_to_q () {
  89         perl -pe 'y/\000/Q/'
  90 }
  91
  92 q_to_nul () {
  93         perl -pe 'y/Q/\000/'
  94 }
  95
  96 q_to_cr () {
  97         tr Q '\015'
  98 }
  99
 100 q_to_tab () {
 101         tr Q '\011'
 102 }
 103
 104 qz_to_tab_space () {
 105         tr QZ '\011\040'
 106 }
 107
 108 append_cr () {
 109         sed -e 's/$/Q/' | tr Q '\015'
 110 }
 111
 112 remove_cr () {
 113         tr '\015' Q | sed -e 's/Q$//'
 114 }
 115
 116 # In some bourne shell implementations, the "unset" builtin returns
 117 # nonzero status when a variable to be unset was not set in the first
 118 # place.
 119 #
 120 # Use sane_unset when that should not be considered an error.
 121
 122 sane_unset () {
 123         unset "$@"
 124         return 0
 125 }
 126
 127 test_tick () {
 128         if test -z "${test_tick+set}"
 129         then
 130                 test_tick=1112911993
 131         else
 132                 test_tick=$(($test_tick + 60))
 133         fi
 134         GIT_COMMITTER_DATE="$test_tick -0700"
 135         GIT_AUTHOR_DATE="$test_tick -0700"
 136         export GIT_COMMITTER_DATE GIT_AUTHOR_DATE
 137 }
 138
 139 # Stop execution and start a shell. This is useful for debugging tests.
 140 #
 141 # Be sure to remove all invocations of this command before submitting.
 142
 143 test_pause () {
 144         "$SHELL_PATH" <&6 >&5 2>&7
 145 }
 146
 147 # Wrap git in gdb. Adding this to a command can make it easier to
 148 # understand what is going on in a failing test.
 149 #
 150 # Example: "debug git checkout master".
 151 debug () {
 152          GIT_TEST_GDB=1 "$@" <&6 >&5 2>&7
 153 }
 154
 155 # Call test_commit with the arguments
 156 # [-C <directory>] <message> [<file> [<contents> [<tag>]]]"
 157 #
 158 # This will commit a file with the given contents and the given commit
 159 # message, and tag the resulting commit with the given tag name.
 160 #
 161 # <file>, <contents>, and <tag> all default to <message>.
 162 #
 163 # If the first argument is "-C", the second argument is used as a path for
 164 # the git invocations.
 165
 166 test_commit () {
 167         notick= &&
 168         signoff= &&
 169         indir= &&
 170         while test $# != 0
 171         do
 172                 case "$1" in
 173                 --notick)
 174                         notick=yes
 175                         ;;
 176                 --signoff)
 177                         signoff="$1"
 178                         ;;
 179                 -C)
 180                         indir="$2"
 181                         shift
 182                         ;;
 183                 *)
 184                         break
 185                         ;;
 186                 esac
 187                 shift
 188         done &&
 189         indir=${indir:+"$indir"/} &&
 190         file=${2:-"$1.t"} &&
 191         echo "${3-$1}" > "$indir$file" &&
 192         git ${indir:+ -C "$indir"} add "$file" &&
 193         if test -z "$notick"
 194         then
 195                 test_tick
 196         fi &&
 197         git ${indir:+ -C "$indir"} commit $signoff -m "$1" &&
 198         git ${indir:+ -C "$indir"} tag "${4:-$1}"
 199 }
 200
 201 # Call test_merge with the arguments "<message> <commit>", where <commit>
 202 # can be a tag pointing to the commit-to-merge.
 203
 204 test_merge () {
 205         test_tick &&
 206         git merge -m "$1" "$2" &&
 207         git tag "$1"
 208 }
 209
 210 # This function helps systems where core.filemode=false is set.
 211 # Use it instead of plain 'chmod +x' to set or unset the executable bit
 212 # of a file in the working directory and add it to the index.
 213
 214 test_chmod () {
 215         chmod "$@" &&
 216         git update-index --add "--chmod=$@"
 217 }
 218
 219 # Unset a configuration variable, but don't fail if it doesn't exist.
 220 test_unconfig () {
 221         config_dir=
 222         if test "$1" = -C
 223         then
 224                 shift
 225                 config_dir=$1
 226                 shift
 227         fi
 228         git ${config_dir:+-C "$config_dir"} config --unset-all "$@"
 229         config_status=$?
 230         case "$config_status" in
 231         5) # ok, nothing to unset
 232                 config_status=0
 233                 ;;
 234         esac
 235         return $config_status
 236 }
 237
 238 # Set git config, automatically unsetting it after the test is over.
 239 test_config () {
 240         config_dir=
 241         if test "$1" = -C
 242         then
 243                 shift
 244                 config_dir=$1
 245                 shift
 246         fi
 247         test_when_finished "test_unconfig ${config_dir:+-C '$config_dir'} '$1'" &&
 248         git ${config_dir:+-C "$config_dir"} config "$@"
 249 }
 250
 251 test_config_global () {
 252         test_when_finished "test_unconfig --global '$1'" &&
 253         git config --global "$@"
 254 }
 255
 256 write_script () {
 257         {
 258                 echo "#!${2-"$SHELL_PATH"}" &&
 259                 cat
 260         } >"$1" &&
 261         chmod +x "$1"
 262 }
 263
 264 # Use test_set_prereq to tell that a particular prerequisite is available.
 265 # The prerequisite can later be checked for in two ways:
 266 #
 267 # - Explicitly using test_have_prereq.
 268 #
 269 # - Implicitly by specifying the prerequisite tag in the calls to
 270 #   test_expect_{success,failure,code}.
 271 #
 272 # The single parameter is the prerequisite tag (a simple word, in all
 273 # capital letters by convention).
 274
 275 test_set_prereq () {
 276         satisfied_prereq="$satisfied_prereq$1 "
 277 }
 278 satisfied_prereq=" "
 279 lazily_testable_prereq= lazily_tested_prereq=
 280
 281 # Usage: test_lazy_prereq PREREQ 'script'
 282 test_lazy_prereq () {
 283         lazily_testable_prereq="$lazily_testable_prereq$1 "
 284         eval test_prereq_lazily_$1=\$2
 285 }
 286
 287 test_run_lazy_prereq_ () {
 288         script='
 289 mkdir -p "$TRASH_DIRECTORY/prereq-test-dir" &&
 290 (
 291         cd "$TRASH_DIRECTORY/prereq-test-dir" &&'"$2"'
 292 )'
 293         say >&3 "checking prerequisite: $1"
 294         say >&3 "$script"
 295         test_eval_ "$script"
 296         eval_ret=$?
 297         rm -rf "$TRASH_DIRECTORY/prereq-test-dir"
 298         if test "$eval_ret" = 0; then
 299                 say >&3 "prerequisite $1 ok"
 300         else
 301                 say >&3 "prerequisite $1 not satisfied"
 302         fi
 303         return $eval_ret
 304 }
 305
 306 test_have_prereq () {
 307         # prerequisites can be concatenated with ','
 308         save_IFS=$IFS
 309         IFS=,
 310         set -- $*
 311         IFS=$save_IFS
 312
 313         total_prereq=0
 314         ok_prereq=0
 315         missing_prereq=
 316
 317         for prerequisite
 318         do
 319                 case "$prerequisite" in
 320                 !*)
 321                         negative_prereq=t
 322                         prerequisite=${prerequisite#!}
 323                         ;;
 324                 *)
 325                         negative_prereq=
 326                 esac
 327
 328                 case " $lazily_tested_prereq " in
 329                 *" $prerequisite "*)
 330                         ;;
 331                 *)
 332                         case " $lazily_testable_prereq " in
 333                         *" $prerequisite "*)
 334                                 eval "script=\$test_prereq_lazily_$prerequisite" &&
 335                                 if test_run_lazy_prereq_ "$prerequisite" "$script"
 336                                 then
 337                                         test_set_prereq $prerequisite
 338                                 fi
 339                                 lazily_tested_prereq="$lazily_tested_prereq$prerequisite "
 340                         esac
 341                         ;;
 342                 esac
 343
 344                 total_prereq=$(($total_prereq + 1))
 345                 case "$satisfied_prereq" in
 346                 *" $prerequisite "*)
 347                         satisfied_this_prereq=t
 348                         ;;
 349                 *)
 350                         satisfied_this_prereq=
 351                 esac
 352
 353                 case "$satisfied_this_prereq,$negative_prereq" in
 354                 t,|,t)
 355                         ok_prereq=$(($ok_prereq + 1))
 356                         ;;
 357                 *)
 358                         # Keep a list of missing prerequisites; restore
 359                         # the negative marker if necessary.
 360                         prerequisite=${negative_prereq:+!}$prerequisite
 361                         if test -z "$missing_prereq"
 362                         then
 363                                 missing_prereq=$prerequisite
 364                         else
 365                                 missing_prereq="$prerequisite,$missing_prereq"
 366                         fi
 367                 esac
 368         done
 369
 370         test $total_prereq = $ok_prereq
 371 }
 372
 373 test_declared_prereq () {
 374         case ",$test_prereq," in
 375         *,$1,*)
 376                 return 0
 377                 ;;
 378         esac
 379         return 1
 380 }
 381
 382 test_verify_prereq () {
 383         test -z "$test_prereq" ||
 384         expr >/dev/null "$test_prereq" : '[A-Z0-9_,!]*$' ||
 385         error "bug in the test script: '$test_prereq' does not look like a prereq"
 386 }
 387
 388 test_expect_failure () {
 389         test_start_
 390         test "$#" = 3 && { test_prereq=$1; shift; } || test_prereq=
 391         test "$#" = 2 ||
 392         error "bug in the test script: not 2 or 3 parameters to test-expect-failure"
 393         test_verify_prereq
 394         export test_prereq
 395         if ! test_skip "$@"
 396         then
 397                 say >&3 "checking known breakage: $2"
 398                 if test_run_ "$2" expecting_failure
 399                 then
 400                         test_known_broken_ok_ "$1"
 401                 else
 402                         test_known_broken_failure_ "$1"
 403                 fi
 404         fi
 405         test_finish_
 406 }
 407
 408 test_expect_success () {
 409         test_start_
 410         test "$#" = 3 && { test_prereq=$1; shift; } || test_prereq=
 411         test "$#" = 2 ||
 412         error "bug in the test script: not 2 or 3 parameters to test-expect-success"
 413         test_verify_prereq
 414         export test_prereq
 415         if ! test_skip "$@"
 416         then
 417                 say >&3 "expecting success: $2"
 418                 if test_run_ "$2"
 419                 then
 420                         test_ok_ "$1"
 421                 else
 422                         test_failure_ "$@"
 423                 fi
 424         fi
 425         test_finish_
 426 }
 427
 428 # test_external runs external test scripts that provide continuous
 429 # test output about their progress, and succeeds/fails on
 430 # zero/non-zero exit code.  It outputs the test output on stdout even
 431 # in non-verbose mode, and announces the external script with "# run
 432 # <n>: ..." before running it.  When providing relative paths, keep in
 433 # mind that all scripts run in "trash directory".
 434 # Usage: test_external description command arguments...
 435 # Example: test_external 'Perl API' perl ../path/to/test.pl
 436 test_external () {
 437         test "$#" = 4 && { test_prereq=$1; shift; } || test_prereq=
 438         test "$#" = 3 ||
 439         error >&5 "bug in the test script: not 3 or 4 parameters to test_external"
 440         descr="$1"
 441         shift
 442         test_verify_prereq
 443         export test_prereq
 444         if ! test_skip "$descr" "$@"
 445         then
 446                 # Announce the script to reduce confusion about the
 447                 # test output that follows.
 448                 say_color "" "# run $test_count: $descr ($*)"
 449                 # Export TEST_DIRECTORY, TRASH_DIRECTORY and GIT_TEST_LONG
 450                 # to be able to use them in script
 451                 export TEST_DIRECTORY TRASH_DIRECTORY GIT_TEST_LONG
 452                 # Run command; redirect its stderr to &4 as in
 453                 # test_run_, but keep its stdout on our stdout even in
 454                 # non-verbose mode.
 455                 "$@" 2>&4
 456                 if test "$?" = 0
 457                 then
 458                         if test $test_external_has_tap -eq 0; then
 459                                 test_ok_ "$descr"
 460                         else
 461                                 say_color "" "# test_external test $descr was ok"
 462                                 test_success=$(($test_success + 1))
 463                         fi
 464                 else
 465                         if test $test_external_has_tap -eq 0; then
 466                                 test_failure_ "$descr" "$@"
 467                         else
 468                                 say_color error "# test_external test $descr failed: $@"
 469                                 test_failure=$(($test_failure + 1))
 470                         fi
 471                 fi
 472         fi
 473 }
 474
 475 # Like test_external, but in addition tests that the command generated
 476 # no output on stderr.
 477 test_external_without_stderr () {
 478         # The temporary file has no (and must have no) security
 479         # implications.
 480         tmp=${TMPDIR:-/tmp}
 481         stderr="$tmp/git-external-stderr.$$.tmp"
 482         test_external "$@" 4> "$stderr"
 483         test -f "$stderr" || error "Internal error: $stderr disappeared."
 484         descr="no stderr: $1"
 485         shift
 486         say >&3 "# expecting no stderr from previous command"
 487         if test ! -s "$stderr"
 488         then
 489                 rm "$stderr"
 490
 491                 if test $test_external_has_tap -eq 0; then
 492                         test_ok_ "$descr"
 493                 else
 494                         say_color "" "# test_external_without_stderr test $descr was ok"
 495                         test_success=$(($test_success + 1))
 496                 fi
 497         else
 498                 if test "$verbose" = t
 499                 then
 500                         output=$(echo; echo "# Stderr is:"; cat "$stderr")
 501                 else
 502                         output=
 503                 fi
 504                 # rm first in case test_failure exits.
 505                 rm "$stderr"
 506                 if test $test_external_has_tap -eq 0; then
 507                         test_failure_ "$descr" "$@" "$output"
 508                 else
 509                         say_color error "# test_external_without_stderr test $descr failed: $@: $output"
 510                         test_failure=$(($test_failure + 1))
 511                 fi
 512         fi
 513 }
 514
 515 # debugging-friendly alternatives to "test [-f|-d|-e]"
 516 # The commands test the existence or non-existence of $1. $2 can be
 517 # given to provide a more precise diagnosis.
 518 test_path_is_file () {
 519         if ! test -f "$1"
 520         then
 521                 echo "File $1 doesn't exist. $2"
 522                 false
 523         fi
 524 }
 525
 526 test_path_is_dir () {
 527         if ! test -d "$1"
 528         then
 529                 echo "Directory $1 doesn't exist. $2"
 530                 false
 531         fi
 532 }
 533
 534 # Check if the directory exists and is empty as expected, barf otherwise.
 535 test_dir_is_empty () {
 536         test_path_is_dir "$1" &&
 537         if test -n "$(ls -a1 "$1" | egrep -v '^\.\.?$')"
 538         then
 539                 echo "Directory '$1' is not empty, it contains:"
 540                 ls -la "$1"
 541                 return 1
 542         fi
 543 }
 544
 545 test_path_is_missing () {
 546         if test -e "$1"
 547         then
 548                 echo "Path exists:"
 549                 ls -ld "$1"
 550                 if test $# -ge 1
 551                 then
 552                         echo "$*"
 553                 fi
 554                 false
 555         fi
 556 }
 557
 558 # test_line_count checks that a file has the number of lines it
 559 # ought to. For example:
 560 #
 561 #       test_expect_success 'produce exactly one line of output' '
 562 #               do something >output &&
 563 #               test_line_count = 1 output
 564 #       '
 565 #
 566 # is like "test $(wc -l <output) = 1" except that it passes the
 567 # output through when the number of lines is wrong.
 568
 569 test_line_count () {
 570         if test $# != 3
 571         then
 572                 error "bug in the test script: not 3 parameters to test_line_count"
 573         elif ! test $(wc -l <"$3") "$1" "$2"
 574         then
 575                 echo "test_line_count: line count for $3 !$1 $2"
 576                 cat "$3"
 577                 return 1
 578         fi
 579 }
 580
 581 # Returns success if a comma separated string of keywords ($1) contains a
 582 # given keyword ($2).
 583 # Examples:
 584 # `list_contains "foo,bar" bar` returns 0
 585 # `list_contains "foo" bar` returns 1
 586
 587 list_contains () {
 588         case ",$1," in
 589         *,$2,*)
 590                 return 0
 591                 ;;
 592         esac
 593         return 1
 594 }
 595
 596 # This is not among top-level (test_expect_success | test_expect_failure)
 597 # but is a prefix that can be used in the test script, like:
 598 #
 599 #       test_expect_success 'complain and die' '
 600 #           do something &&
 601 #           do something else &&
 602 #           test_must_fail git checkout ../outerspace
 603 #       '
 604 #
 605 # Writing this as "! git checkout ../outerspace" is wrong, because
 606 # the failure could be due to a segv.  We want a controlled failure.
 607
 608 test_must_fail () {
 609         case "$1" in
 610         ok=*)
 611                 _test_ok=${1#ok=}
 612                 shift
 613                 ;;
 614         *)
 615                 _test_ok=
 616                 ;;
 617         esac
 618         "$@"
 619         exit_code=$?
 620         if test $exit_code -eq 0 && ! list_contains "$_test_ok" success
 621         then
 622                 echo >&2 "test_must_fail: command succeeded: $*"
 623                 return 1
 624         elif test_match_signal 13 $exit_code && list_contains "$_test_ok" sigpipe
 625         then
 626                 return 0
 627         elif test $exit_code -gt 129 && test $exit_code -le 192
 628         then
 629                 echo >&2 "test_must_fail: died by signal $(($exit_code - 128)): $*"
 630                 return 1
 631         elif test $exit_code -eq 127
 632         then
 633                 echo >&2 "test_must_fail: command not found: $*"
 634                 return 1
 635         elif test $exit_code -eq 126
 636         then
 637                 echo >&2 "test_must_fail: valgrind error: $*"
 638                 return 1
 639         fi
 640         return 0
 641 }
 642
 643 # Similar to test_must_fail, but tolerates success, too.  This is
 644 # meant to be used in contexts like:
 645 #
 646 #       test_expect_success 'some command works without configuration' '
 647 #               test_might_fail git config --unset all.configuration &&
 648 #               do something
 649 #       '
 650 #
 651 # Writing "git config --unset all.configuration || :" would be wrong,
 652 # because we want to notice if it fails due to segv.
 653
 654 test_might_fail () {
 655         test_must_fail ok=success "$@"
 656 }
 657
 658 # Similar to test_must_fail and test_might_fail, but check that a
 659 # given command exited with a given exit code. Meant to be used as:
 660 #
 661 #       test_expect_success 'Merge with d/f conflicts' '
 662 #               test_expect_code 1 git merge "merge msg" B master
 663 #       '
 664
 665 test_expect_code () {
 666         want_code=$1
 667         shift
 668         "$@"
 669         exit_code=$?
 670         if test $exit_code = $want_code
 671         then
 672                 return 0
 673         fi
 674
 675         echo >&2 "test_expect_code: command exited with $exit_code, we wanted $want_code $*"
 676         return 1
 677 }
 678
 679 # test_cmp is a helper function to compare actual and expected output.
 680 # You can use it like:
 681 #
 682 #       test_expect_success 'foo works' '
 683 #               echo expected >expected &&
 684 #               foo >actual &&
 685 #               test_cmp expected actual
 686 #       '
 687 #
 688 # This could be written as either "cmp" or "diff -u", but:
 689 # - cmp's output is not nearly as easy to read as diff -u
 690 # - not all diff versions understand "-u"
 691
 692 test_cmp() {
 693         $GIT_TEST_CMP "$@"
 694 }
 695
 696 # test_cmp_bin - helper to compare binary files
 697
 698 test_cmp_bin() {
 699         cmp "$@"
 700 }
 701
 702 # Call any command "$@" but be more verbose about its
 703 # failure. This is handy for commands like "test" which do
 704 # not output anything when they fail.
 705 verbose () {
 706         "$@" && return 0
 707         echo >&2 "command failed: $(git rev-parse --sq-quote "$@")"
 708         return 1
 709 }
 710
 711 # Check if the file expected to be empty is indeed empty, and barfs
 712 # otherwise.
 713
 714 test_must_be_empty () {
 715         if test -s "$1"
 716         then
 717                 echo "'$1' is not empty, it contains:"
 718                 cat "$1"
 719                 return 1
 720         fi
 721 }
 722
 723 # Tests that its two parameters refer to the same revision
 724 test_cmp_rev () {
 725         git rev-parse --verify "$1" >expect.rev &&
 726         git rev-parse --verify "$2" >actual.rev &&
 727         test_cmp expect.rev actual.rev
 728 }
 729
 730 # Print a sequence of integers in increasing order, either with
 731 # two arguments (start and end):
 732 #
 733 #     test_seq 1 5 -- outputs 1 2 3 4 5 one line at a time
 734 #
 735 # or with one argument (end), in which case it starts counting
 736 # from 1.
 737
 738 test_seq () {
 739         case $# in
 740         1)      set 1 "$@" ;;
 741         2)      ;;
 742         *)      error "bug in the test script: not 1 or 2 parameters to test_seq" ;;
 743         esac
 744         test_seq_counter__=$1
 745         while test "$test_seq_counter__" -le "$2"
 746         do
 747                 echo "$test_seq_counter__"
 748                 test_seq_counter__=$(( $test_seq_counter__ + 1 ))
 749         done
 750 }
 751
 752 # This function can be used to schedule some commands to be run
 753 # unconditionally at the end of the test to restore sanity:
 754 #
 755 #       test_expect_success 'test core.capslock' '
 756 #               git config core.capslock true &&
 757 #               test_when_finished "git config --unset core.capslock" &&
 758 #               hello world
 759 #       '
 760 #
 761 # That would be roughly equivalent to
 762 #
 763 #       test_expect_success 'test core.capslock' '
 764 #               git config core.capslock true &&
 765 #               hello world
 766 #               git config --unset core.capslock
 767 #       '
 768 #
 769 # except that the greeting and config --unset must both succeed for
 770 # the test to pass.
 771 #
 772 # Note that under --immediate mode, no clean-up is done to help diagnose
 773 # what went wrong.
 774
 775 test_when_finished () {
 776         # We cannot detect when we are in a subshell in general, but by
 777         # doing so on Bash is better than nothing (the test will
 778         # silently pass on other shells).
 779         test "${BASH_SUBSHELL-0}" = 0 ||
 780         error "bug in test script: test_when_finished does nothing in a subshell"
 781         test_cleanup="{ $*
 782                 } && (exit \"\$eval_ret\"); eval_ret=\$?; $test_cleanup"
 783 }
 784
 785 # Most tests can use the created repository, but some may need to create more.
 786 # Usage: test_create_repo <directory>
 787 test_create_repo () {
 788         test "$#" = 1 ||
 789         error "bug in the test script: not 1 parameter to test-create-repo"
 790         repo="$1"
 791         mkdir -p "$repo"
 792         (
 793                 cd "$repo" || error "Cannot setup test environment"
 794                 "$GIT_EXEC_PATH/git-init" "--template=$GIT_BUILD_DIR/templates/blt/" >&3 2>&4 ||
 795                 error "cannot run git init -- have you built things yet?"
 796                 mv .git/hooks .git/hooks-disabled
 797         ) || exit
 798 }
 799
 800 # This function helps on symlink challenged file systems when it is not
 801 # important that the file system entry is a symbolic link.
 802 # Use test_ln_s_add instead of "ln -s x y && git add y" to add a
 803 # symbolic link entry y to the index.
 804
 805 test_ln_s_add () {
 806         if test_have_prereq SYMLINKS
 807         then
 808                 ln -s "$1" "$2" &&
 809                 git update-index --add "$2"
 810         else
 811                 printf '%s' "$1" >"$2" &&
 812                 ln_s_obj=$(git hash-object -w "$2") &&
 813                 git update-index --add --cacheinfo 120000 $ln_s_obj "$2" &&
 814                 # pick up stat info from the file
 815                 git update-index "$2"
 816         fi
 817 }
 818
 819 # This function writes out its parameters, one per line
 820 test_write_lines () {
 821         printf "%s\n" "$@"
 822 }
 823
 824 perl () {
 825         command "$PERL_PATH" "$@"
 826 }
 827
 828 # Is the value one of the various ways to spell a boolean true/false?
 829 test_normalize_bool () {
 830         git -c magic.variable="$1" config --bool magic.variable 2>/dev/null
 831 }
 832
 833 # Given a variable $1, normalize the value of it to one of "true",
 834 # "false", or "auto" and store the result to it.
 835 #
 836 #     test_tristate GIT_TEST_HTTPD
 837 #
 838 # A variable set to an empty string is set to 'false'.
 839 # A variable set to 'false' or 'auto' keeps its value.
 840 # Anything else is set to 'true'.
 841 # An unset variable defaults to 'auto'.
 842 #
 843 # The last rule is to allow people to set the variable to an empty
 844 # string and export it to decline testing the particular feature
 845 # for versions both before and after this change.  We used to treat
 846 # both unset and empty variable as a signal for "do not test" and
 847 # took any non-empty string as "please test".
 848
 849 test_tristate () {
 850         if eval "test x\"\${$1+isset}\" = xisset"
 851         then
 852                 # explicitly set
 853                 eval "
 854                         case \"\$$1\" in
 855                         '')     $1=false ;;
 856                         auto)   ;;
 857                         *)      $1=\$(test_normalize_bool \$$1 || echo true) ;;
 858                         esac
 859                 "
 860         else
 861                 eval "$1=auto"
 862         fi
 863 }
 864
 865 # Exit the test suite, either by skipping all remaining tests or by
 866 # exiting with an error. If "$1" is "auto", we then we assume we were
 867 # opportunistically trying to set up some tests and we skip. If it is
 868 # "true", then we report a failure.
 869 #
 870 # The error/skip message should be given by $2.
 871 #
 872 test_skip_or_die () {
 873         case "$1" in
 874         auto)
 875                 skip_all=$2
 876                 test_done
 877                 ;;
 878         true)
 879                 error "$2"
 880                 ;;
 881         *)
 882                 error "BUG: test tristate is '$1' (real error: $2)"
 883         esac
 884 }
 885
 886 # The following mingw_* functions obey POSIX shell syntax, but are actually
 887 # bash scripts, and are meant to be used only with bash on Windows.
 888
 889 # A test_cmp function that treats LF and CRLF equal and avoids to fork
 890 # diff when possible.
 891 mingw_test_cmp () {
 892         # Read text into shell variables and compare them. If the results
 893         # are different, use regular diff to report the difference.
 894         local test_cmp_a= test_cmp_b=
 895
 896         # When text came from stdin (one argument is '-') we must feed it
 897         # to diff.
 898         local stdin_for_diff=
 899
 900         # Since it is difficult to detect the difference between an
 901         # empty input file and a failure to read the files, we go straight
 902         # to diff if one of the inputs is empty.
 903         if test -s "$1" && test -s "$2"
 904         then
 905                 # regular case: both files non-empty
 906                 mingw_read_file_strip_cr_ test_cmp_a <"$1"
 907                 mingw_read_file_strip_cr_ test_cmp_b <"$2"
 908         elif test -s "$1" && test "$2" = -
 909         then
 910                 # read 2nd file from stdin
 911                 mingw_read_file_strip_cr_ test_cmp_a <"$1"
 912                 mingw_read_file_strip_cr_ test_cmp_b
 913                 stdin_for_diff='<<<"$test_cmp_b"'
 914         elif test "$1" = - && test -s "$2"
 915         then
 916                 # read 1st file from stdin
 917                 mingw_read_file_strip_cr_ test_cmp_a
 918                 mingw_read_file_strip_cr_ test_cmp_b <"$2"
 919                 stdin_for_diff='<<<"$test_cmp_a"'
 920         fi
 921         test -n "$test_cmp_a" &&
 922         test -n "$test_cmp_b" &&
 923         test "$test_cmp_a" = "$test_cmp_b" ||
 924         eval "diff -u \"\$@\" $stdin_for_diff"
 925 }
 926
 927 # $1 is the name of the shell variable to fill in
 928 mingw_read_file_strip_cr_ () {
 929         # Read line-wise using LF as the line separator
 930         # and use IFS to strip CR.
 931         local line
 932         while :
 933         do
 934                 if IFS=$'\r' read -r -d $'\n' line
 935                 then
 936                         # good
 937                         line=$line$'\n'
 938                 else
 939                         # we get here at EOF, but also if the last line
 940                         # was not terminated by LF; in the latter case,
 941                         # some text was read
 942                         if test -z "$line"
 943                         then
 944                                 # EOF, really
 945                                 break
 946                         fi
 947                 fi
 948                 eval "$1=\$$1\$line"
 949         done
 950 }
 951
 952 # Like "env FOO=BAR some-program", but run inside a subshell, which means
 953 # it also works for shell functions (though those functions cannot impact
 954 # the environment outside of the test_env invocation).
 955 test_env () {
 956         (
 957                 while test $# -gt 0
 958                 do
 959                         case "$1" in
 960                         *=*)
 961                                 eval "${1%%=*}=\${1#*=}"
 962                                 eval "export ${1%%=*}"
 963                                 shift
 964                                 ;;
 965                         *)
 966                                 "$@"
 967                                 exit
 968                                 ;;
 969                         esac
 970                 done
 971         )
 972 }
 973
 974 # Returns true if the numeric exit code in "$2" represents the expected signal
 975 # in "$1". Signals should be given numerically.
 976 test_match_signal () {
 977         if test "$2" = "$((128 + $1))"
 978         then
 979                 # POSIX
 980                 return 0
 981         elif test "$2" = "$((256 + $1))"
 982         then
 983                 # ksh
 984                 return 0
 985         fi
 986         return 1
 987 }
 988
 989 # Read up to "$1" bytes (or to EOF) from stdin and write them to stdout.
 990 test_copy_bytes () {
 991         perl -e '
 992                 my $len = $ARGV[1];
 993                 while ($len > 0) {
 994                         my $s;
 995                         my $nread = sysread(STDIN, $s, $len);
 996                         die "cannot read: $!" unless defined($nread);
 997                         print $s;
 998                         $len -= $nread;
 999                 }
1000         ' - "$1"
1001 }
1002
1003 # run "$@" inside a non-git directory
1004 nongit () {
1005         test -d non-repo ||
1006         mkdir non-repo ||
1007         return 1
1008
1009         (
1010                 GIT_CEILING_DIRECTORIES=$(pwd) &&
1011                 export GIT_CEILING_DIRECTORIES &&
1012                 cd non-repo &&
1013                 "$@"
1014         )
1015 }