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t / test-lib-functions.shon commit Merge branch 'ls/p4-test-updates' (d94447d)
   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.
  28test_set_editor () {
  29        FAKE_EDITOR="$1"
  30        export FAKE_EDITOR
  31        EDITOR='"$FAKE_EDITOR"'
  32        export EDITOR
  33}
  34
  35test_set_index_version () {
  36    GIT_INDEX_VERSION="$1"
  37    export GIT_INDEX_VERSION
  38}
  39
  40test_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($0) - RSTART - RLENGTH + 1);
  78                        }
  79                        print
  80                }
  81        '
  82}
  83
  84nul_to_q () {
  85        perl -pe 'y/\000/Q/'
  86}
  87
  88q_to_nul () {
  89        perl -pe 'y/Q/\000/'
  90}
  91
  92q_to_cr () {
  93        tr Q '\015'
  94}
  95
  96q_to_tab () {
  97        tr Q '\011'
  98}
  99
 100qz_to_tab_space () {
 101        tr QZ '\011\040'
 102}
 103
 104append_cr () {
 105        sed -e 's/$/Q/' | tr Q '\015'
 106}
 107
 108remove_cr () {
 109        tr '\015' Q | sed -e 's/Q$//'
 110}
 111
 112# In some bourne shell implementations, the "unset" builtin returns
 113# nonzero status when a variable to be unset was not set in the first
 114# place.
 115#
 116# Use sane_unset when that should not be considered an error.
 117
 118sane_unset () {
 119        unset "$@"
 120        return 0
 121}
 122
 123test_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="$test_tick -0700"
 132        export GIT_COMMITTER_DATE GIT_AUTHOR_DATE
 133}
 134
 135# Stop execution and start a shell. This is useful for debugging tests and
 136# only makes sense together with "-v".
 137#
 138# Be sure to remove all invocations of this command before submitting.
 139
 140test_pause () {
 141        if test "$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
 155test_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
 187test_merge () {
 188        test_tick &&
 189        git merge -m "$1" "$2" &&
 190        git tag "$1"
 191}
 192
 193# This function helps systems where core.filemode=false is set.
 194# Use it instead of plain 'chmod +x' to set or unset the executable bit
 195# of a file in the working directory and add it to the index.
 196
 197test_chmod () {
 198        chmod "$@" &&
 199        git update-index --add "--chmod=$@"
 200}
 201
 202# Unset a configuration variable, but don't fail if it doesn't exist.
 203test_unconfig () {
 204        config_dir=
 205        if test "$1" = -C
 206        then
 207                shift
 208                config_dir=$1
 209                shift
 210        fi
 211        git ${config_dir:+-C "$config_dir"} config --unset-all "$@"
 212        config_status=$?
 213        case "$config_status" in
 214        5) # ok, nothing to unset
 215                config_status=0
 216                ;;
 217        esac
 218        return $config_status
 219}
 220
 221# Set git config, automatically unsetting it after the test is over.
 222test_config () {
 223        config_dir=
 224        if test "$1" = -C
 225        then
 226                shift
 227                config_dir=$1
 228                shift
 229        fi
 230        test_when_finished "test_unconfig ${config_dir:+-C '$config_dir'} '$1'" &&
 231        git ${config_dir:+-C "$config_dir"} config "$@"
 232}
 233
 234test_config_global () {
 235        test_when_finished "test_unconfig --global '$1'" &&
 236        git config --global "$@"
 237}
 238
 239write_script () {
 240        {
 241                echo "#!${2-"$SHELL_PATH"}" &&
 242                cat
 243        } >"$1" &&
 244        chmod +x "$1"
 245}
 246
 247# Use test_set_prereq to tell that a particular prerequisite is available.
 248# The prerequisite can later be checked for in two ways:
 249#
 250# - Explicitly using test_have_prereq.
 251#
 252# - Implicitly by specifying the prerequisite tag in the calls to
 253#   test_expect_{success,failure,code}.
 254#
 255# The single parameter is the prerequisite tag (a simple word, in all
 256# capital letters by convention).
 257
 258test_set_prereq () {
 259        satisfied_prereq="$satisfied_prereq$1 "
 260}
 261satisfied_prereq=" "
 262lazily_testable_prereq= lazily_tested_prereq=
 263
 264# Usage: test_lazy_prereq PREREQ 'script'
 265test_lazy_prereq () {
 266        lazily_testable_prereq="$lazily_testable_prereq$1 "
 267        eval test_prereq_lazily_$1=\$2
 268}
 269
 270test_run_lazy_prereq_ () {
 271        script='
 272mkdir -p "$TRASH_DIRECTORY/prereq-test-dir" &&
 273(
 274        cd "$TRASH_DIRECTORY/prereq-test-dir" &&'"$2"'
 275)'
 276        say >&3 "checking prerequisite: $1"
 277        say >&3 "$script"
 278        test_eval_ "$script"
 279        eval_ret=$?
 280        rm -rf "$TRASH_DIRECTORY/prereq-test-dir"
 281        if test "$eval_ret" = 0; then
 282                say >&3 "prerequisite $1 ok"
 283        else
 284                say >&3 "prerequisite $1 not satisfied"
 285        fi
 286        return $eval_ret
 287}
 288
 289test_have_prereq () {
 290        # prerequisites can be concatenated with ','
 291        save_IFS=$IFS
 292        IFS=,
 293        set -- $*
 294        IFS=$save_IFS
 295
 296        total_prereq=0
 297        ok_prereq=0
 298        missing_prereq=
 299
 300        for prerequisite
 301        do
 302                case "$prerequisite" in
 303                !*)
 304                        negative_prereq=t
 305                        prerequisite=${prerequisite#!}
 306                        ;;
 307                *)
 308                        negative_prereq=
 309                esac
 310
 311                case " $lazily_tested_prereq " in
 312                *" $prerequisite "*)
 313                        ;;
 314                *)
 315                        case " $lazily_testable_prereq " in
 316                        *" $prerequisite "*)
 317                                eval "script=\$test_prereq_lazily_$prerequisite" &&
 318                                if test_run_lazy_prereq_ "$prerequisite" "$script"
 319                                then
 320                                        test_set_prereq $prerequisite
 321                                fi
 322                                lazily_tested_prereq="$lazily_tested_prereq$prerequisite "
 323                        esac
 324                        ;;
 325                esac
 326
 327                total_prereq=$(($total_prereq + 1))
 328                case "$satisfied_prereq" in
 329                *" $prerequisite "*)
 330                        satisfied_this_prereq=t
 331                        ;;
 332                *)
 333                        satisfied_this_prereq=
 334                esac
 335
 336                case "$satisfied_this_prereq,$negative_prereq" in
 337                t,|,t)
 338                        ok_prereq=$(($ok_prereq + 1))
 339                        ;;
 340                *)
 341                        # Keep a list of missing prerequisites; restore
 342                        # the negative marker if necessary.
 343                        prerequisite=${negative_prereq:+!}$prerequisite
 344                        if test -z "$missing_prereq"
 345                        then
 346                                missing_prereq=$prerequisite
 347                        else
 348                                missing_prereq="$prerequisite,$missing_prereq"
 349                        fi
 350                esac
 351        done
 352
 353        test $total_prereq = $ok_prereq
 354}
 355
 356test_declared_prereq () {
 357        case ",$test_prereq," in
 358        *,$1,*)
 359                return 0
 360                ;;
 361        esac
 362        return 1
 363}
 364
 365test_verify_prereq () {
 366        test -z "$test_prereq" ||
 367        expr >/dev/null "$test_prereq" : '[A-Z0-9_,!]*$' ||
 368        error "bug in the test script: '$test_prereq' does not look like a prereq"
 369}
 370
 371test_expect_failure () {
 372        test_start_
 373        test "$#" = 3 && { test_prereq=$1; shift; } || test_prereq=
 374        test "$#" = 2 ||
 375        error "bug in the test script: not 2 or 3 parameters to test-expect-failure"
 376        test_verify_prereq
 377        export test_prereq
 378        if ! test_skip "$@"
 379        then
 380                say >&3 "checking known breakage: $2"
 381                if test_run_ "$2" expecting_failure
 382                then
 383                        test_known_broken_ok_ "$1"
 384                else
 385                        test_known_broken_failure_ "$1"
 386                fi
 387        fi
 388        test_finish_
 389}
 390
 391test_expect_success () {
 392        test_start_
 393        test "$#" = 3 && { test_prereq=$1; shift; } || test_prereq=
 394        test "$#" = 2 ||
 395        error "bug in the test script: not 2 or 3 parameters to test-expect-success"
 396        test_verify_prereq
 397        export test_prereq
 398        if ! test_skip "$@"
 399        then
 400                say >&3 "expecting success: $2"
 401                if test_run_ "$2"
 402                then
 403                        test_ok_ "$1"
 404                else
 405                        test_failure_ "$@"
 406                fi
 407        fi
 408        test_finish_
 409}
 410
 411# test_external runs external test scripts that provide continuous
 412# test output about their progress, and succeeds/fails on
 413# zero/non-zero exit code.  It outputs the test output on stdout even
 414# in non-verbose mode, and announces the external script with "# run
 415# <n>: ..." before running it.  When providing relative paths, keep in
 416# mind that all scripts run in "trash directory".
 417# Usage: test_external description command arguments...
 418# Example: test_external 'Perl API' perl ../path/to/test.pl
 419test_external () {
 420        test "$#" = 4 && { test_prereq=$1; shift; } || test_prereq=
 421        test "$#" = 3 ||
 422        error >&5 "bug in the test script: not 3 or 4 parameters to test_external"
 423        descr="$1"
 424        shift
 425        test_verify_prereq
 426        export test_prereq
 427        if ! test_skip "$descr" "$@"
 428        then
 429                # Announce the script to reduce confusion about the
 430                # test output that follows.
 431                say_color "" "# run $test_count: $descr ($*)"
 432                # Export TEST_DIRECTORY, TRASH_DIRECTORY and GIT_TEST_LONG
 433                # to be able to use them in script
 434                export TEST_DIRECTORY TRASH_DIRECTORY GIT_TEST_LONG
 435                # Run command; redirect its stderr to &4 as in
 436                # test_run_, but keep its stdout on our stdout even in
 437                # non-verbose mode.
 438                "$@" 2>&4
 439                if test "$?" = 0
 440                then
 441                        if test $test_external_has_tap -eq 0; then
 442                                test_ok_ "$descr"
 443                        else
 444                                say_color "" "# test_external test $descr was ok"
 445                                test_success=$(($test_success + 1))
 446                        fi
 447                else
 448                        if test $test_external_has_tap -eq 0; then
 449                                test_failure_ "$descr" "$@"
 450                        else
 451                                say_color error "# test_external test $descr failed: $@"
 452                                test_failure=$(($test_failure + 1))
 453                        fi
 454                fi
 455        fi
 456}
 457
 458# Like test_external, but in addition tests that the command generated
 459# no output on stderr.
 460test_external_without_stderr () {
 461        # The temporary file has no (and must have no) security
 462        # implications.
 463        tmp=${TMPDIR:-/tmp}
 464        stderr="$tmp/git-external-stderr.$$.tmp"
 465        test_external "$@" 4> "$stderr"
 466        test -f "$stderr" || error "Internal error: $stderr disappeared."
 467        descr="no stderr: $1"
 468        shift
 469        say >&3 "# expecting no stderr from previous command"
 470        if test ! -s "$stderr"
 471        then
 472                rm "$stderr"
 473
 474                if test $test_external_has_tap -eq 0; then
 475                        test_ok_ "$descr"
 476                else
 477                        say_color "" "# test_external_without_stderr test $descr was ok"
 478                        test_success=$(($test_success + 1))
 479                fi
 480        else
 481                if test "$verbose" = t
 482                then
 483                        output=$(echo; echo "# Stderr is:"; cat "$stderr")
 484                else
 485                        output=
 486                fi
 487                # rm first in case test_failure exits.
 488                rm "$stderr"
 489                if test $test_external_has_tap -eq 0; then
 490                        test_failure_ "$descr" "$@" "$output"
 491                else
 492                        say_color error "# test_external_without_stderr test $descr failed: $@: $output"
 493                        test_failure=$(($test_failure + 1))
 494                fi
 495        fi
 496}
 497
 498# debugging-friendly alternatives to "test [-f|-d|-e]"
 499# The commands test the existence or non-existence of $1. $2 can be
 500# given to provide a more precise diagnosis.
 501test_path_is_file () {
 502        if ! test -f "$1"
 503        then
 504                echo "File $1 doesn't exist. $2"
 505                false
 506        fi
 507}
 508
 509test_path_is_dir () {
 510        if ! test -d "$1"
 511        then
 512                echo "Directory $1 doesn't exist. $2"
 513                false
 514        fi
 515}
 516
 517# Check if the directory exists and is empty as expected, barf otherwise.
 518test_dir_is_empty () {
 519        test_path_is_dir "$1" &&
 520        if test -n "$(ls -a1 "$1" | egrep -v '^\.\.?$')"
 521        then
 522                echo "Directory '$1' is not empty, it contains:"
 523                ls -la "$1"
 524                return 1
 525        fi
 526}
 527
 528test_path_is_missing () {
 529        if test -e "$1"
 530        then
 531                echo "Path exists:"
 532                ls -ld "$1"
 533                if test $# -ge 1
 534                then
 535                        echo "$*"
 536                fi
 537                false
 538        fi
 539}
 540
 541# test_line_count checks that a file has the number of lines it
 542# ought to. For example:
 543#
 544#       test_expect_success 'produce exactly one line of output' '
 545#               do something >output &&
 546#               test_line_count = 1 output
 547#       '
 548#
 549# is like "test $(wc -l <output) = 1" except that it passes the
 550# output through when the number of lines is wrong.
 551
 552test_line_count () {
 553        if test $# != 3
 554        then
 555                error "bug in the test script: not 3 parameters to test_line_count"
 556        elif ! test $(wc -l <"$3") "$1" "$2"
 557        then
 558                echo "test_line_count: line count for $3 !$1 $2"
 559                cat "$3"
 560                return 1
 561        fi
 562}
 563
 564# This is not among top-level (test_expect_success | test_expect_failure)
 565# but is a prefix that can be used in the test script, like:
 566#
 567#       test_expect_success 'complain and die' '
 568#           do something &&
 569#           do something else &&
 570#           test_must_fail git checkout ../outerspace
 571#       '
 572#
 573# Writing this as "! git checkout ../outerspace" is wrong, because
 574# the failure could be due to a segv.  We want a controlled failure.
 575
 576test_must_fail () {
 577        "$@"
 578        exit_code=$?
 579        if test $exit_code = 0; then
 580                echo >&2 "test_must_fail: command succeeded: $*"
 581                return 1
 582        elif test $exit_code -gt 129 && test $exit_code -le 192; then
 583                echo >&2 "test_must_fail: died by signal: $*"
 584                return 1
 585        elif test $exit_code = 127; then
 586                echo >&2 "test_must_fail: command not found: $*"
 587                return 1
 588        elif test $exit_code = 126; then
 589                echo >&2 "test_must_fail: valgrind error: $*"
 590                return 1
 591        fi
 592        return 0
 593}
 594
 595# Similar to test_must_fail, but tolerates success, too.  This is
 596# meant to be used in contexts like:
 597#
 598#       test_expect_success 'some command works without configuration' '
 599#               test_might_fail git config --unset all.configuration &&
 600#               do something
 601#       '
 602#
 603# Writing "git config --unset all.configuration || :" would be wrong,
 604# because we want to notice if it fails due to segv.
 605
 606test_might_fail () {
 607        "$@"
 608        exit_code=$?
 609        if test $exit_code -gt 129 && test $exit_code -le 192; then
 610                echo >&2 "test_might_fail: died by signal: $*"
 611                return 1
 612        elif test $exit_code = 127; then
 613                echo >&2 "test_might_fail: command not found: $*"
 614                return 1
 615        fi
 616        return 0
 617}
 618
 619# Similar to test_must_fail and test_might_fail, but check that a
 620# given command exited with a given exit code. Meant to be used as:
 621#
 622#       test_expect_success 'Merge with d/f conflicts' '
 623#               test_expect_code 1 git merge "merge msg" B master
 624#       '
 625
 626test_expect_code () {
 627        want_code=$1
 628        shift
 629        "$@"
 630        exit_code=$?
 631        if test $exit_code = $want_code
 632        then
 633                return 0
 634        fi
 635
 636        echo >&2 "test_expect_code: command exited with $exit_code, we wanted $want_code $*"
 637        return 1
 638}
 639
 640# test_cmp is a helper function to compare actual and expected output.
 641# You can use it like:
 642#
 643#       test_expect_success 'foo works' '
 644#               echo expected >expected &&
 645#               foo >actual &&
 646#               test_cmp expected actual
 647#       '
 648#
 649# This could be written as either "cmp" or "diff -u", but:
 650# - cmp's output is not nearly as easy to read as diff -u
 651# - not all diff versions understand "-u"
 652
 653test_cmp() {
 654        $GIT_TEST_CMP "$@"
 655}
 656
 657# test_cmp_bin - helper to compare binary files
 658
 659test_cmp_bin() {
 660        cmp "$@"
 661}
 662
 663# Call any command "$@" but be more verbose about its
 664# failure. This is handy for commands like "test" which do
 665# not output anything when they fail.
 666verbose () {
 667        "$@" && return 0
 668        echo >&2 "command failed: $(git rev-parse --sq-quote "$@")"
 669        return 1
 670}
 671
 672# Check if the file expected to be empty is indeed empty, and barfs
 673# otherwise.
 674
 675test_must_be_empty () {
 676        if test -s "$1"
 677        then
 678                echo "'$1' is not empty, it contains:"
 679                cat "$1"
 680                return 1
 681        fi
 682}
 683
 684# Tests that its two parameters refer to the same revision
 685test_cmp_rev () {
 686        git rev-parse --verify "$1" >expect.rev &&
 687        git rev-parse --verify "$2" >actual.rev &&
 688        test_cmp expect.rev actual.rev
 689}
 690
 691# Print a sequence of numbers or letters in increasing order.  This is
 692# similar to GNU seq(1), but the latter might not be available
 693# everywhere (and does not do letters).  It may be used like:
 694#
 695#       for i in $(test_seq 100)
 696#       do
 697#               for j in $(test_seq 10 20)
 698#               do
 699#                       for k in $(test_seq a z)
 700#                       do
 701#                               echo $i-$j-$k
 702#                       done
 703#               done
 704#       done
 705
 706test_seq () {
 707        case $# in
 708        1)      set 1 "$@" ;;
 709        2)      ;;
 710        *)      error "bug in the test script: not 1 or 2 parameters to test_seq" ;;
 711        esac
 712        perl -le 'print for $ARGV[0]..$ARGV[1]' -- "$@"
 713}
 714
 715# This function can be used to schedule some commands to be run
 716# unconditionally at the end of the test to restore sanity:
 717#
 718#       test_expect_success 'test core.capslock' '
 719#               git config core.capslock true &&
 720#               test_when_finished "git config --unset core.capslock" &&
 721#               hello world
 722#       '
 723#
 724# That would be roughly equivalent to
 725#
 726#       test_expect_success 'test core.capslock' '
 727#               git config core.capslock true &&
 728#               hello world
 729#               git config --unset core.capslock
 730#       '
 731#
 732# except that the greeting and config --unset must both succeed for
 733# the test to pass.
 734#
 735# Note that under --immediate mode, no clean-up is done to help diagnose
 736# what went wrong.
 737
 738test_when_finished () {
 739        # We cannot detect when we are in a subshell in general, but by
 740        # doing so on Bash is better than nothing (the test will
 741        # silently pass on other shells).
 742        test "${BASH_SUBSHELL-0}" = 0 ||
 743        error "bug in test script: test_when_finished does nothing in a subshell"
 744        test_cleanup="{ $*
 745                } && (exit \"\$eval_ret\"); eval_ret=\$?; $test_cleanup"
 746}
 747
 748# Most tests can use the created repository, but some may need to create more.
 749# Usage: test_create_repo <directory>
 750test_create_repo () {
 751        test "$#" = 1 ||
 752        error "bug in the test script: not 1 parameter to test-create-repo"
 753        repo="$1"
 754        mkdir -p "$repo"
 755        (
 756                cd "$repo" || error "Cannot setup test environment"
 757                "$GIT_EXEC_PATH/git-init" "--template=$GIT_BUILD_DIR/templates/blt/" >&3 2>&4 ||
 758                error "cannot run git init -- have you built things yet?"
 759                mv .git/hooks .git/hooks-disabled
 760        ) || exit
 761}
 762
 763# This function helps on symlink challenged file systems when it is not
 764# important that the file system entry is a symbolic link.
 765# Use test_ln_s_add instead of "ln -s x y && git add y" to add a
 766# symbolic link entry y to the index.
 767
 768test_ln_s_add () {
 769        if test_have_prereq SYMLINKS
 770        then
 771                ln -s "$1" "$2" &&
 772                git update-index --add "$2"
 773        else
 774                printf '%s' "$1" >"$2" &&
 775                ln_s_obj=$(git hash-object -w "$2") &&
 776                git update-index --add --cacheinfo 120000 $ln_s_obj "$2" &&
 777                # pick up stat info from the file
 778                git update-index "$2"
 779        fi
 780}
 781
 782# This function writes out its parameters, one per line
 783test_write_lines () {
 784        printf "%s\n" "$@"
 785}
 786
 787perl () {
 788        command "$PERL_PATH" "$@"
 789}
 790
 791# Is the value one of the various ways to spell a boolean true/false?
 792test_normalize_bool () {
 793        git -c magic.variable="$1" config --bool magic.variable 2>/dev/null
 794}
 795
 796# Given a variable $1, normalize the value of it to one of "true",
 797# "false", or "auto" and store the result to it.
 798#
 799#     test_tristate GIT_TEST_HTTPD
 800#
 801# A variable set to an empty string is set to 'false'.
 802# A variable set to 'false' or 'auto' keeps its value.
 803# Anything else is set to 'true'.
 804# An unset variable defaults to 'auto'.
 805#
 806# The last rule is to allow people to set the variable to an empty
 807# string and export it to decline testing the particular feature
 808# for versions both before and after this change.  We used to treat
 809# both unset and empty variable as a signal for "do not test" and
 810# took any non-empty string as "please test".
 811
 812test_tristate () {
 813        if eval "test x\"\${$1+isset}\" = xisset"
 814        then
 815                # explicitly set
 816                eval "
 817                        case \"\$$1\" in
 818                        '')     $1=false ;;
 819                        auto)   ;;
 820                        *)      $1=\$(test_normalize_bool \$$1 || echo true) ;;
 821                        esac
 822                "
 823        else
 824                eval "$1=auto"
 825        fi
 826}
 827
 828# Exit the test suite, either by skipping all remaining tests or by
 829# exiting with an error. If "$1" is "auto", we then we assume we were
 830# opportunistically trying to set up some tests and we skip. If it is
 831# "true", then we report a failure.
 832#
 833# The error/skip message should be given by $2.
 834#
 835test_skip_or_die () {
 836        case "$1" in
 837        auto)
 838                skip_all=$2
 839                test_done
 840                ;;
 841        true)
 842                error "$2"
 843                ;;
 844        *)
 845                error "BUG: test tristate is '$1' (real error: $2)"
 846        esac
 847}
 848
 849# The following mingw_* functions obey POSIX shell syntax, but are actually
 850# bash scripts, and are meant to be used only with bash on Windows.
 851
 852# A test_cmp function that treats LF and CRLF equal and avoids to fork
 853# diff when possible.
 854mingw_test_cmp () {
 855        # Read text into shell variables and compare them. If the results
 856        # are different, use regular diff to report the difference.
 857        local test_cmp_a= test_cmp_b=
 858
 859        # When text came from stdin (one argument is '-') we must feed it
 860        # to diff.
 861        local stdin_for_diff=
 862
 863        # Since it is difficult to detect the difference between an
 864        # empty input file and a failure to read the files, we go straight
 865        # to diff if one of the inputs is empty.
 866        if test -s "$1" && test -s "$2"
 867        then
 868                # regular case: both files non-empty
 869                mingw_read_file_strip_cr_ test_cmp_a <"$1"
 870                mingw_read_file_strip_cr_ test_cmp_b <"$2"
 871        elif test -s "$1" && test "$2" = -
 872        then
 873                # read 2nd file from stdin
 874                mingw_read_file_strip_cr_ test_cmp_a <"$1"
 875                mingw_read_file_strip_cr_ test_cmp_b
 876                stdin_for_diff='<<<"$test_cmp_b"'
 877        elif test "$1" = - && test -s "$2"
 878        then
 879                # read 1st file from stdin
 880                mingw_read_file_strip_cr_ test_cmp_a
 881                mingw_read_file_strip_cr_ test_cmp_b <"$2"
 882                stdin_for_diff='<<<"$test_cmp_a"'
 883        fi
 884        test -n "$test_cmp_a" &&
 885        test -n "$test_cmp_b" &&
 886        test "$test_cmp_a" = "$test_cmp_b" ||
 887        eval "diff -u \"\$@\" $stdin_for_diff"
 888}
 889
 890# $1 is the name of the shell variable to fill in
 891mingw_read_file_strip_cr_ () {
 892        # Read line-wise using LF as the line separator
 893        # and use IFS to strip CR.
 894        local line
 895        while :
 896        do
 897                if IFS=$'\r' read -r -d $'\n' line
 898                then
 899                        # good
 900                        line=$line$'\n'
 901                else
 902                        # we get here at EOF, but also if the last line
 903                        # was not terminated by LF; in the latter case,
 904                        # some text was read
 905                        if test -z "$line"
 906                        then
 907                                # EOF, really
 908                                break
 909                        fi
 910                fi
 911                eval "$1=\$$1\$line"
 912        done
 913}