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($0) - RSTART - RLENGTH + 1);
  78                         }
  79                         print
  80                 }
  81         '
  82 }
  83
  84 nul_to_q () {
  85         perl -pe 'y/\000/Q/'
  86 }
  87
  88 q_to_nul () {
  89         perl -pe 'y/Q/\000/'
  90 }
  91
  92 q_to_cr () {
  93         tr Q '\015'
  94 }
  95
  96 q_to_tab () {
  97         tr Q '\011'
  98 }
  99
 100 qz_to_tab_space () {
 101         tr QZ '\011\040'
 102 }
 103
 104 append_cr () {
 105         sed -e 's/$/Q/' | tr Q '\015'
 106 }
 107
 108 remove_cr () {
 109         tr '\015' Q | sed -e 's/Q$//'
 110 }
 111
 112 # In some bourne shell implementations, the "unset" builtin returns
 113 # nonzero status when a variable to be unset was not set in the first
 114 # place.
 115 #
 116 # Use sane_unset when that should not be considered an error.
 117
 118 sane_unset () {
 119         unset "$@"
 120         return 0
 121 }
 122
 123 test_tick () {
 124         if test -z "${test_tick+set}"
 125         then
 126                 test_tick=1112911993
 127         else
 128                 test_tick=$(($test_tick + 60))
 129         fi
 130         GIT_COMMITTER_DATE="$test_tick -0700"
 131         GIT_AUTHOR_DATE="$test_tick -0700"
 132         export GIT_COMMITTER_DATE GIT_AUTHOR_DATE
 133 }
 134
 135 # Stop execution and start a shell. This is useful for debugging tests and
 136 # only makes sense together with "-v".
 137 #
 138 # Be sure to remove all invocations of this command before submitting.
 139
 140 test_pause () {
 141         if test "$verbose" = t; then
 142                 "$SHELL_PATH" <&6 >&3 2>&4
 143         else
 144                 error >&5 "test_pause requires --verbose"
 145         fi
 146 }
 147
 148 # Call test_commit with the arguments "<message> [<file> [<contents> [<tag>]]]"
 149 #
 150 # This will commit a file with the given contents and the given commit
 151 # message, and tag the resulting commit with the given tag name.
 152 #
 153 # <file>, <contents>, and <tag> all default to <message>.
 154
 155 test_commit () {
 156         notick= &&
 157         signoff= &&
 158         while test $# != 0
 159         do
 160                 case "$1" in
 161                 --notick)
 162                         notick=yes
 163                         ;;
 164                 --signoff)
 165                         signoff="$1"
 166                         ;;
 167                 *)
 168                         break
 169                         ;;
 170                 esac
 171                 shift
 172         done &&
 173         file=${2:-"$1.t"} &&
 174         echo "${3-$1}" > "$file" &&
 175         git add "$file" &&
 176         if test -z "$notick"
 177         then
 178                 test_tick
 179         fi &&
 180         git commit $signoff -m "$1" &&
 181         git tag "${4:-$1}"
 182 }
 183
 184 # Call test_merge with the arguments "<message> <commit>", where <commit>
 185 # can be a tag pointing to the commit-to-merge.
 186
 187 test_merge () {
 188         test_tick &&
 189         git merge -m "$1" "$2" &&
 190         git tag "$1"
 191 }
 192
 193 # This function helps systems where core.filemode=false is set.
 194 # Use it instead of plain 'chmod +x' to set or unset the executable bit
 195 # of a file in the working directory and add it to the index.
 196
 197 test_chmod () {
 198         chmod "$@" &&
 199         git update-index --add "--chmod=$@"
 200 }
 201
 202 # Unset a configuration variable, but don't fail if it doesn't exist.
 203 test_unconfig () {
 204         git config --unset-all "$@"
 205         config_status=$?
 206         case "$config_status" in
 207         5) # ok, nothing to unset
 208                 config_status=0
 209                 ;;
 210         esac
 211         return $config_status
 212 }
 213
 214 # Set git config, automatically unsetting it after the test is over.
 215 test_config () {
 216         test_when_finished "test_unconfig '$1'" &&
 217         git config "$@"
 218 }
 219
 220 test_config_global () {
 221         test_when_finished "test_unconfig --global '$1'" &&
 222         git config --global "$@"
 223 }
 224
 225 write_script () {
 226         {
 227                 echo "#!${2-"$SHELL_PATH"}" &&
 228                 cat
 229         } >"$1" &&
 230         chmod +x "$1"
 231 }
 232
 233 # Use test_set_prereq to tell that a particular prerequisite is available.
 234 # The prerequisite can later be checked for in two ways:
 235 #
 236 # - Explicitly using test_have_prereq.
 237 #
 238 # - Implicitly by specifying the prerequisite tag in the calls to
 239 #   test_expect_{success,failure,code}.
 240 #
 241 # The single parameter is the prerequisite tag (a simple word, in all
 242 # capital letters by convention).
 243
 244 test_set_prereq () {
 245         satisfied_prereq="$satisfied_prereq$1 "
 246 }
 247 satisfied_prereq=" "
 248 lazily_testable_prereq= lazily_tested_prereq=
 249
 250 # Usage: test_lazy_prereq PREREQ 'script'
 251 test_lazy_prereq () {
 252         lazily_testable_prereq="$lazily_testable_prereq$1 "
 253         eval test_prereq_lazily_$1=\$2
 254 }
 255
 256 test_run_lazy_prereq_ () {
 257         script='
 258 mkdir -p "$TRASH_DIRECTORY/prereq-test-dir" &&
 259 (
 260         cd "$TRASH_DIRECTORY/prereq-test-dir" &&'"$2"'
 261 )'
 262         say >&3 "checking prerequisite: $1"
 263         say >&3 "$script"
 264         test_eval_ "$script"
 265         eval_ret=$?
 266         rm -rf "$TRASH_DIRECTORY/prereq-test-dir"
 267         if test "$eval_ret" = 0; then
 268                 say >&3 "prerequisite $1 ok"
 269         else
 270                 say >&3 "prerequisite $1 not satisfied"
 271         fi
 272         return $eval_ret
 273 }
 274
 275 test_have_prereq () {
 276         # prerequisites can be concatenated with ','
 277         save_IFS=$IFS
 278         IFS=,
 279         set -- $*
 280         IFS=$save_IFS
 281
 282         total_prereq=0
 283         ok_prereq=0
 284         missing_prereq=
 285
 286         for prerequisite
 287         do
 288                 case "$prerequisite" in
 289                 !*)
 290                         negative_prereq=t
 291                         prerequisite=${prerequisite#!}
 292                         ;;
 293                 *)
 294                         negative_prereq=
 295                 esac
 296
 297                 case " $lazily_tested_prereq " in
 298                 *" $prerequisite "*)
 299                         ;;
 300                 *)
 301                         case " $lazily_testable_prereq " in
 302                         *" $prerequisite "*)
 303                                 eval "script=\$test_prereq_lazily_$prerequisite" &&
 304                                 if test_run_lazy_prereq_ "$prerequisite" "$script"
 305                                 then
 306                                         test_set_prereq $prerequisite
 307                                 fi
 308                                 lazily_tested_prereq="$lazily_tested_prereq$prerequisite "
 309                         esac
 310                         ;;
 311                 esac
 312
 313                 total_prereq=$(($total_prereq + 1))
 314                 case "$satisfied_prereq" in
 315                 *" $prerequisite "*)
 316                         satisfied_this_prereq=t
 317                         ;;
 318                 *)
 319                         satisfied_this_prereq=
 320                 esac
 321
 322                 case "$satisfied_this_prereq,$negative_prereq" in
 323                 t,|,t)
 324                         ok_prereq=$(($ok_prereq + 1))
 325                         ;;
 326                 *)
 327                         # Keep a list of missing prerequisites; restore
 328                         # the negative marker if necessary.
 329                         prerequisite=${negative_prereq:+!}$prerequisite
 330                         if test -z "$missing_prereq"
 331                         then
 332                                 missing_prereq=$prerequisite
 333                         else
 334                                 missing_prereq="$prerequisite,$missing_prereq"
 335                         fi
 336                 esac
 337         done
 338
 339         test $total_prereq = $ok_prereq
 340 }
 341
 342 test_declared_prereq () {
 343         case ",$test_prereq," in
 344         *,$1,*)
 345                 return 0
 346                 ;;
 347         esac
 348         return 1
 349 }
 350
 351 test_expect_failure () {
 352         test_start_
 353         test "$#" = 3 && { test_prereq=$1; shift; } || test_prereq=
 354         test "$#" = 2 ||
 355         error "bug in the test script: not 2 or 3 parameters to test-expect-failure"
 356         export test_prereq
 357         if ! test_skip "$@"
 358         then
 359                 say >&3 "checking known breakage: $2"
 360                 if test_run_ "$2" expecting_failure
 361                 then
 362                         test_known_broken_ok_ "$1"
 363                 else
 364                         test_known_broken_failure_ "$1"
 365                 fi
 366         fi
 367         test_finish_
 368 }
 369
 370 test_expect_success () {
 371         test_start_
 372         test "$#" = 3 && { test_prereq=$1; shift; } || test_prereq=
 373         test "$#" = 2 ||
 374         error "bug in the test script: not 2 or 3 parameters to test-expect-success"
 375         export test_prereq
 376         if ! test_skip "$@"
 377         then
 378                 say >&3 "expecting success: $2"
 379                 if test_run_ "$2"
 380                 then
 381                         test_ok_ "$1"
 382                 else
 383                         test_failure_ "$@"
 384                 fi
 385         fi
 386         test_finish_
 387 }
 388
 389 # test_external runs external test scripts that provide continuous
 390 # test output about their progress, and succeeds/fails on
 391 # zero/non-zero exit code.  It outputs the test output on stdout even
 392 # in non-verbose mode, and announces the external script with "# run
 393 # <n>: ..." before running it.  When providing relative paths, keep in
 394 # mind that all scripts run in "trash directory".
 395 # Usage: test_external description command arguments...
 396 # Example: test_external 'Perl API' perl ../path/to/test.pl
 397 test_external () {
 398         test "$#" = 4 && { test_prereq=$1; shift; } || test_prereq=
 399         test "$#" = 3 ||
 400         error >&5 "bug in the test script: not 3 or 4 parameters to test_external"
 401         descr="$1"
 402         shift
 403         export test_prereq
 404         if ! test_skip "$descr" "$@"
 405         then
 406                 # Announce the script to reduce confusion about the
 407                 # test output that follows.
 408                 say_color "" "# run $test_count: $descr ($*)"
 409                 # Export TEST_DIRECTORY, TRASH_DIRECTORY and GIT_TEST_LONG
 410                 # to be able to use them in script
 411                 export TEST_DIRECTORY TRASH_DIRECTORY GIT_TEST_LONG
 412                 # Run command; redirect its stderr to &4 as in
 413                 # test_run_, but keep its stdout on our stdout even in
 414                 # non-verbose mode.
 415                 "$@" 2>&4
 416                 if test "$?" = 0
 417                 then
 418                         if test $test_external_has_tap -eq 0; then
 419                                 test_ok_ "$descr"
 420                         else
 421                                 say_color "" "# test_external test $descr was ok"
 422                                 test_success=$(($test_success + 1))
 423                         fi
 424                 else
 425                         if test $test_external_has_tap -eq 0; then
 426                                 test_failure_ "$descr" "$@"
 427                         else
 428                                 say_color error "# test_external test $descr failed: $@"
 429                                 test_failure=$(($test_failure + 1))
 430                         fi
 431                 fi
 432         fi
 433 }
 434
 435 # Like test_external, but in addition tests that the command generated
 436 # no output on stderr.
 437 test_external_without_stderr () {
 438         # The temporary file has no (and must have no) security
 439         # implications.
 440         tmp=${TMPDIR:-/tmp}
 441         stderr="$tmp/git-external-stderr.$$.tmp"
 442         test_external "$@" 4> "$stderr"
 443         test -f "$stderr" || error "Internal error: $stderr disappeared."
 444         descr="no stderr: $1"
 445         shift
 446         say >&3 "# expecting no stderr from previous command"
 447         if test ! -s "$stderr"
 448         then
 449                 rm "$stderr"
 450
 451                 if test $test_external_has_tap -eq 0; then
 452                         test_ok_ "$descr"
 453                 else
 454                         say_color "" "# test_external_without_stderr test $descr was ok"
 455                         test_success=$(($test_success + 1))
 456                 fi
 457         else
 458                 if test "$verbose" = t
 459                 then
 460                         output=$(echo; echo "# Stderr is:"; cat "$stderr")
 461                 else
 462                         output=
 463                 fi
 464                 # rm first in case test_failure exits.
 465                 rm "$stderr"
 466                 if test $test_external_has_tap -eq 0; then
 467                         test_failure_ "$descr" "$@" "$output"
 468                 else
 469                         say_color error "# test_external_without_stderr test $descr failed: $@: $output"
 470                         test_failure=$(($test_failure + 1))
 471                 fi
 472         fi
 473 }
 474
 475 # debugging-friendly alternatives to "test [-f|-d|-e]"
 476 # The commands test the existence or non-existence of $1. $2 can be
 477 # given to provide a more precise diagnosis.
 478 test_path_is_file () {
 479         if ! test -f "$1"
 480         then
 481                 echo "File $1 doesn't exist. $*"
 482                 false
 483         fi
 484 }
 485
 486 test_path_is_dir () {
 487         if ! test -d "$1"
 488         then
 489                 echo "Directory $1 doesn't exist. $*"
 490                 false
 491         fi
 492 }
 493
 494 # Check if the directory exists and is empty as expected, barf otherwise.
 495 test_dir_is_empty () {
 496         test_path_is_dir "$1" &&
 497         if test -n "$(ls -a1 "$1" | egrep -v '^\.\.?$')"
 498         then
 499                 echo "Directory '$1' is not empty, it contains:"
 500                 ls -la "$1"
 501                 return 1
 502         fi
 503 }
 504
 505 test_path_is_missing () {
 506         if test -e "$1"
 507         then
 508                 echo "Path exists:"
 509                 ls -ld "$1"
 510                 if test $# -ge 1
 511                 then
 512                         echo "$*"
 513                 fi
 514                 false
 515         fi
 516 }
 517
 518 # test_line_count checks that a file has the number of lines it
 519 # ought to. For example:
 520 #
 521 #       test_expect_success 'produce exactly one line of output' '
 522 #               do something >output &&
 523 #               test_line_count = 1 output
 524 #       '
 525 #
 526 # is like "test $(wc -l <output) = 1" except that it passes the
 527 # output through when the number of lines is wrong.
 528
 529 test_line_count () {
 530         if test $# != 3
 531         then
 532                 error "bug in the test script: not 3 parameters to test_line_count"
 533         elif ! test $(wc -l <"$3") "$1" "$2"
 534         then
 535                 echo "test_line_count: line count for $3 !$1 $2"
 536                 cat "$3"
 537                 return 1
 538         fi
 539 }
 540
 541 # This is not among top-level (test_expect_success | test_expect_failure)
 542 # but is a prefix that can be used in the test script, like:
 543 #
 544 #       test_expect_success 'complain and die' '
 545 #           do something &&
 546 #           do something else &&
 547 #           test_must_fail git checkout ../outerspace
 548 #       '
 549 #
 550 # Writing this as "! git checkout ../outerspace" is wrong, because
 551 # the failure could be due to a segv.  We want a controlled failure.
 552
 553 test_must_fail () {
 554         "$@"
 555         exit_code=$?
 556         if test $exit_code = 0; then
 557                 echo >&2 "test_must_fail: command succeeded: $*"
 558                 return 1
 559         elif test $exit_code -gt 129 && test $exit_code -le 192; then
 560                 echo >&2 "test_must_fail: died by signal: $*"
 561                 return 1
 562         elif test $exit_code = 127; then
 563                 echo >&2 "test_must_fail: command not found: $*"
 564                 return 1
 565         elif test $exit_code = 126; then
 566                 echo >&2 "test_must_fail: valgrind error: $*"
 567                 return 1
 568         fi
 569         return 0
 570 }
 571
 572 # Similar to test_must_fail, but tolerates success, too.  This is
 573 # meant to be used in contexts like:
 574 #
 575 #       test_expect_success 'some command works without configuration' '
 576 #               test_might_fail git config --unset all.configuration &&
 577 #               do something
 578 #       '
 579 #
 580 # Writing "git config --unset all.configuration || :" would be wrong,
 581 # because we want to notice if it fails due to segv.
 582
 583 test_might_fail () {
 584         "$@"
 585         exit_code=$?
 586         if test $exit_code -gt 129 && test $exit_code -le 192; then
 587                 echo >&2 "test_might_fail: died by signal: $*"
 588                 return 1
 589         elif test $exit_code = 127; then
 590                 echo >&2 "test_might_fail: command not found: $*"
 591                 return 1
 592         fi
 593         return 0
 594 }
 595
 596 # Similar to test_must_fail and test_might_fail, but check that a
 597 # given command exited with a given exit code. Meant to be used as:
 598 #
 599 #       test_expect_success 'Merge with d/f conflicts' '
 600 #               test_expect_code 1 git merge "merge msg" B master
 601 #       '
 602
 603 test_expect_code () {
 604         want_code=$1
 605         shift
 606         "$@"
 607         exit_code=$?
 608         if test $exit_code = $want_code
 609         then
 610                 return 0
 611         fi
 612
 613         echo >&2 "test_expect_code: command exited with $exit_code, we wanted $want_code $*"
 614         return 1
 615 }
 616
 617 # test_cmp is a helper function to compare actual and expected output.
 618 # You can use it like:
 619 #
 620 #       test_expect_success 'foo works' '
 621 #               echo expected >expected &&
 622 #               foo >actual &&
 623 #               test_cmp expected actual
 624 #       '
 625 #
 626 # This could be written as either "cmp" or "diff -u", but:
 627 # - cmp's output is not nearly as easy to read as diff -u
 628 # - not all diff versions understand "-u"
 629
 630 test_cmp() {
 631         $GIT_TEST_CMP "$@"
 632 }
 633
 634 # test_cmp_bin - helper to compare binary files
 635
 636 test_cmp_bin() {
 637         cmp "$@"
 638 }
 639
 640 # Call any command "$@" but be more verbose about its
 641 # failure. This is handy for commands like "test" which do
 642 # not output anything when they fail.
 643 verbose () {
 644         "$@" && return 0
 645         echo >&2 "command failed: $(git rev-parse --sq-quote "$@")"
 646         return 1
 647 }
 648
 649 # Check if the file expected to be empty is indeed empty, and barfs
 650 # otherwise.
 651
 652 test_must_be_empty () {
 653         if test -s "$1"
 654         then
 655                 echo "'$1' is not empty, it contains:"
 656                 cat "$1"
 657                 return 1
 658         fi
 659 }
 660
 661 # Tests that its two parameters refer to the same revision
 662 test_cmp_rev () {
 663         git rev-parse --verify "$1" >expect.rev &&
 664         git rev-parse --verify "$2" >actual.rev &&
 665         test_cmp expect.rev actual.rev
 666 }
 667
 668 # Print a sequence of numbers or letters in increasing order.  This is
 669 # similar to GNU seq(1), but the latter might not be available
 670 # everywhere (and does not do letters).  It may be used like:
 671 #
 672 #       for i in $(test_seq 100)
 673 #       do
 674 #               for j in $(test_seq 10 20)
 675 #               do
 676 #                       for k in $(test_seq a z)
 677 #                       do
 678 #                               echo $i-$j-$k
 679 #                       done
 680 #               done
 681 #       done
 682
 683 test_seq () {
 684         case $# in
 685         1)      set 1 "$@" ;;
 686         2)      ;;
 687         *)      error "bug in the test script: not 1 or 2 parameters to test_seq" ;;
 688         esac
 689         perl -le 'print for $ARGV[0]..$ARGV[1]' -- "$@"
 690 }
 691
 692 # This function can be used to schedule some commands to be run
 693 # unconditionally at the end of the test to restore sanity:
 694 #
 695 #       test_expect_success 'test core.capslock' '
 696 #               git config core.capslock true &&
 697 #               test_when_finished "git config --unset core.capslock" &&
 698 #               hello world
 699 #       '
 700 #
 701 # That would be roughly equivalent to
 702 #
 703 #       test_expect_success 'test core.capslock' '
 704 #               git config core.capslock true &&
 705 #               hello world
 706 #               git config --unset core.capslock
 707 #       '
 708 #
 709 # except that the greeting and config --unset must both succeed for
 710 # the test to pass.
 711 #
 712 # Note that under --immediate mode, no clean-up is done to help diagnose
 713 # what went wrong.
 714
 715 test_when_finished () {
 716         test_cleanup="{ $*
 717                 } && (exit \"\$eval_ret\"); eval_ret=\$?; $test_cleanup"
 718 }
 719
 720 # Most tests can use the created repository, but some may need to create more.
 721 # Usage: test_create_repo <directory>
 722 test_create_repo () {
 723         test "$#" = 1 ||
 724         error "bug in the test script: not 1 parameter to test-create-repo"
 725         repo="$1"
 726         mkdir -p "$repo"
 727         (
 728                 cd "$repo" || error "Cannot setup test environment"
 729                 "$GIT_EXEC_PATH/git-init" "--template=$GIT_BUILD_DIR/templates/blt/" >&3 2>&4 ||
 730                 error "cannot run git init -- have you built things yet?"
 731                 mv .git/hooks .git/hooks-disabled
 732         ) || exit
 733 }
 734
 735 # This function helps on symlink challenged file systems when it is not
 736 # important that the file system entry is a symbolic link.
 737 # Use test_ln_s_add instead of "ln -s x y && git add y" to add a
 738 # symbolic link entry y to the index.
 739
 740 test_ln_s_add () {
 741         if test_have_prereq SYMLINKS
 742         then
 743                 ln -s "$1" "$2" &&
 744                 git update-index --add "$2"
 745         else
 746                 printf '%s' "$1" >"$2" &&
 747                 ln_s_obj=$(git hash-object -w "$2") &&
 748                 git update-index --add --cacheinfo 120000 $ln_s_obj "$2"
 749         fi
 750 }
 751
 752 # This function writes out its parameters, one per line
 753 test_write_lines () {
 754         printf "%s\n" "$@"
 755 }
 756
 757 perl () {
 758         command "$PERL_PATH" "$@"
 759 }
 760
 761 # Is the value one of the various ways to spell a boolean true/false?
 762 test_normalize_bool () {
 763         git -c magic.variable="$1" config --bool magic.variable 2>/dev/null
 764 }
 765
 766 # Given a variable $1, normalize the value of it to one of "true",
 767 # "false", or "auto" and store the result to it.
 768 #
 769 #     test_tristate GIT_TEST_HTTPD
 770 #
 771 # A variable set to an empty string is set to 'false'.
 772 # A variable set to 'false' or 'auto' keeps its value.
 773 # Anything else is set to 'true'.
 774 # An unset variable defaults to 'auto'.
 775 #
 776 # The last rule is to allow people to set the variable to an empty
 777 # string and export it to decline testing the particular feature
 778 # for versions both before and after this change.  We used to treat
 779 # both unset and empty variable as a signal for "do not test" and
 780 # took any non-empty string as "please test".
 781
 782 test_tristate () {
 783         if eval "test x\"\${$1+isset}\" = xisset"
 784         then
 785                 # explicitly set
 786                 eval "
 787                         case \"\$$1\" in
 788                         '')     $1=false ;;
 789                         auto)   ;;
 790                         *)      $1=\$(test_normalize_bool \$$1 || echo true) ;;
 791                         esac
 792                 "
 793         else
 794                 eval "$1=auto"
 795         fi
 796 }
 797
 798 # Exit the test suite, either by skipping all remaining tests or by
 799 # exiting with an error. If "$1" is "auto", we then we assume we were
 800 # opportunistically trying to set up some tests and we skip. If it is
 801 # "true", then we report a failure.
 802 #
 803 # The error/skip message should be given by $2.
 804 #
 805 test_skip_or_die () {
 806         case "$1" in
 807         auto)
 808                 skip_all=$2
 809                 test_done
 810                 ;;
 811         true)
 812                 error "$2"
 813                 ;;
 814         *)
 815                 error "BUG: test tristate is '$1' (real error: $2)"
 816         esac
 817 }
 818
 819 # The following mingw_* functions obey POSIX shell syntax, but are actually
 820 # bash scripts, and are meant to be used only with bash on Windows.
 821
 822 # A test_cmp function that treats LF and CRLF equal and avoids to fork
 823 # diff when possible.
 824 mingw_test_cmp () {
 825         # Read text into shell variables and compare them. If the results
 826         # are different, use regular diff to report the difference.
 827         local test_cmp_a= test_cmp_b=
 828
 829         # When text came from stdin (one argument is '-') we must feed it
 830         # to diff.
 831         local stdin_for_diff=
 832
 833         # Since it is difficult to detect the difference between an
 834         # empty input file and a failure to read the files, we go straight
 835         # to diff if one of the inputs is empty.
 836         if test -s "$1" && test -s "$2"
 837         then
 838                 # regular case: both files non-empty
 839                 mingw_read_file_strip_cr_ test_cmp_a <"$1"
 840                 mingw_read_file_strip_cr_ test_cmp_b <"$2"
 841         elif test -s "$1" && test "$2" = -
 842         then
 843                 # read 2nd file from stdin
 844                 mingw_read_file_strip_cr_ test_cmp_a <"$1"
 845                 mingw_read_file_strip_cr_ test_cmp_b
 846                 stdin_for_diff='<<<"$test_cmp_b"'
 847         elif test "$1" = - && test -s "$2"
 848         then
 849                 # read 1st file from stdin
 850                 mingw_read_file_strip_cr_ test_cmp_a
 851                 mingw_read_file_strip_cr_ test_cmp_b <"$2"
 852                 stdin_for_diff='<<<"$test_cmp_a"'
 853         fi
 854         test -n "$test_cmp_a" &&
 855         test -n "$test_cmp_b" &&
 856         test "$test_cmp_a" = "$test_cmp_b" ||
 857         eval "diff -u \"\$@\" $stdin_for_diff"
 858 }
 859
 860 # $1 is the name of the shell variable to fill in
 861 mingw_read_file_strip_cr_ () {
 862         # Read line-wise using LF as the line separator
 863         # and use IFS to strip CR.
 864         local line
 865         while :
 866         do
 867                 if IFS=$'\r' read -r -d $'\n' line
 868                 then
 869                         # good
 870                         line=$line$'\n'
 871                 else
 872                         # we get here at EOF, but also if the last line
 873                         # was not terminated by LF; in the latter case,
 874                         # some text was read
 875                         if test -z "$line"
 876                         then
 877                                 # EOF, really
 878                                 break
 879                         fi
 880                 fi
 881                 eval "$1=\$$1\$line"
 882         done
 883 }