Merge 1.7.6.4 in

[git] / t / test-lib.sh

#!/bin/sh
#
# Copyright (c) 2005 Junio C Hamano
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see http://www.gnu.org/licenses/ .

# if --tee was passed, write the output not only to the terminal, but
# additionally to the file test-results/$BASENAME.out, too.
case "$GIT_TEST_TEE_STARTED, $* " in
done,*)
        # do not redirect again
        ;;
*' --tee '*|*' --va'*)
        mkdir -p test-results
        BASE=test-results/$(basename "$0" .sh)
        (GIT_TEST_TEE_STARTED=done ${SHELL-sh} "$0" "$@" 2>&1;
         echo $? > $BASE.exit) | tee $BASE.out
        test "$(cat $BASE.exit)" = 0
        exit
        ;;
esac

# Keep the original TERM for say_color
ORIGINAL_TERM=$TERM

# For repeatability, reset the environment to known value.
LANG=C
LC_ALL=C
PAGER=cat
TZ=UTC
TERM=dumb
export LANG LC_ALL PAGER TERM TZ
EDITOR=:
unset VISUAL
unset EMAIL
unset $(perl -e '
        my @env = keys %ENV;
        my $ok = join("|", qw(
                TRACE
                DEBUG
                USE_LOOKUP
                TEST
                .*_TEST
                PROVE
                VALGRIND
        ));
        my @vars = grep(/^GIT_/ && !/^GIT_($ok)/o, @env);
        print join("\n", @vars);
')
GIT_AUTHOR_EMAIL=author@example.com
GIT_AUTHOR_NAME='A U Thor'
GIT_COMMITTER_EMAIL=committer@example.com
GIT_COMMITTER_NAME='C O Mitter'
GIT_MERGE_VERBOSITY=5
export GIT_MERGE_VERBOSITY
export GIT_AUTHOR_EMAIL GIT_AUTHOR_NAME
export GIT_COMMITTER_EMAIL GIT_COMMITTER_NAME
export EDITOR

# Protect ourselves from common misconfiguration to export
# CDPATH into the environment
unset CDPATH

unset GREP_OPTIONS

case $(echo $GIT_TRACE |tr "[A-Z]" "[a-z]") in
        1|2|true)
                echo "* warning: Some tests will not work if GIT_TRACE" \
                        "is set as to trace on STDERR ! *"
                echo "* warning: Please set GIT_TRACE to something" \
                        "other than 1, 2 or true ! *"
                ;;
esac

# Convenience
#
# A regexp to match 5 and 40 hexdigits
_x05='[0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]'
_x40="$_x05$_x05$_x05$_x05$_x05$_x05$_x05$_x05"

# Zero SHA-1
_z40=0000000000000000000000000000000000000000

# Line feed
LF='
'

# Each test should start with something like this, after copyright notices:
#
# test_description='Description of this test...
# This test checks if command xyzzy does the right thing...
# '
# . ./test-lib.sh
[ "x$ORIGINAL_TERM" != "xdumb" ] && (
                TERM=$ORIGINAL_TERM &&
                export TERM &&
                [ -t 1 ] &&
                tput bold >/dev/null 2>&1 &&
                tput setaf 1 >/dev/null 2>&1 &&
                tput sgr0 >/dev/null 2>&1
        ) &&
        color=t

while test "$#" -ne 0
do
        case "$1" in
        -d|--d|--de|--deb|--debu|--debug)
                debug=t; shift ;;
        -i|--i|--im|--imm|--imme|--immed|--immedi|--immedia|--immediat|--immediate)
                immediate=t; shift ;;
        -l|--l|--lo|--lon|--long|--long-|--long-t|--long-te|--long-tes|--long-test|--long-tests)
                GIT_TEST_LONG=t; export GIT_TEST_LONG; shift ;;
        -h|--h|--he|--hel|--help)
                help=t; shift ;;
        -v|--v|--ve|--ver|--verb|--verbo|--verbos|--verbose)
                verbose=t; shift ;;
        -q|--q|--qu|--qui|--quie|--quiet)
                # Ignore --quiet under a TAP::Harness. Saying how many tests
                # passed without the ok/not ok details is always an error.
                test -z "$HARNESS_ACTIVE" && quiet=t; shift ;;
        --with-dashes)
                with_dashes=t; shift ;;
        --no-color)
                color=; shift ;;
        --va|--val|--valg|--valgr|--valgri|--valgrin|--valgrind)
                valgrind=t; verbose=t; shift ;;
        --tee)
                shift ;; # was handled already
        --root=*)
                root=$(expr "z$1" : 'z[^=]*=\(.*\)')
                shift ;;
        *)
                echo "error: unknown test option '$1'" >&2; exit 1 ;;
        esac
done

if test -n "$color"; then
        say_color () {
                (
                TERM=$ORIGINAL_TERM
                export TERM
                case "$1" in
                        error) tput bold; tput setaf 1;; # bold red
                        skip)  tput bold; tput setaf 2;; # bold green
                        pass)  tput setaf 2;;            # green
                        info)  tput setaf 3;;            # brown
                        *) test -n "$quiet" && return;;
                esac
                shift
                printf "%s" "$*"
                tput sgr0
                echo
                )
        }
else
        say_color() {
                test -z "$1" && test -n "$quiet" && return
                shift
                echo "$*"
        }
fi

error () {
        say_color error "error: $*"
        GIT_EXIT_OK=t
        exit 1
}

say () {
        say_color info "$*"
}

test "${test_description}" != "" ||
error "Test script did not set test_description."

if test "$help" = "t"
then
        echo "$test_description"
        exit 0
fi

exec 5>&1
if test "$verbose" = "t"
then
        exec 4>&2 3>&1
else
        exec 4>/dev/null 3>/dev/null
fi

test_failure=0
test_count=0
test_fixed=0
test_broken=0
test_success=0

test_external_has_tap=0

die () {
        code=$?
        if test -n "$GIT_EXIT_OK"
        then
                exit $code
        else
                echo >&5 "FATAL: Unexpected exit with code $code"
                exit 1
        fi
}

GIT_EXIT_OK=
trap 'die' EXIT

# The semantics of the editor variables are that of invoking
# sh -c "$EDITOR \"$@\"" files ...
#
# If our trash directory contains shell metacharacters, they will be
# interpreted if we just set $EDITOR directly, so do a little dance with
# environment variables to work around this.
#
# In particular, quoting isn't enough, as the path may contain the same quote
# that we're using.
test_set_editor () {
        FAKE_EDITOR="$1"
        export FAKE_EDITOR
        EDITOR='"$FAKE_EDITOR"'
        export EDITOR
}

test_decode_color () {
        awk '
                function name(n) {
                        if (n == 0) return "RESET";
                        if (n == 1) return "BOLD";
                        if (n == 30) return "BLACK";
                        if (n == 31) return "RED";
                        if (n == 32) return "GREEN";
                        if (n == 33) return "YELLOW";
                        if (n == 34) return "BLUE";
                        if (n == 35) return "MAGENTA";
                        if (n == 36) return "CYAN";
                        if (n == 37) return "WHITE";
                        if (n == 40) return "BLACK";
                        if (n == 41) return "BRED";
                        if (n == 42) return "BGREEN";
                        if (n == 43) return "BYELLOW";
                        if (n == 44) return "BBLUE";
                        if (n == 45) return "BMAGENTA";
                        if (n == 46) return "BCYAN";
                        if (n == 47) return "BWHITE";
                }
                {
                        while (match($0, /\033\[[0-9;]*m/) != 0) {
                                printf "%s<", substr($0, 1, RSTART-1);
                                codes = substr($0, RSTART+2, RLENGTH-3);
                                if (length(codes) == 0)
                                        printf "%s", name(0)
                                else {
                                        n = split(codes, ary, ";");
                                        sep = "";
                                        for (i = 1; i <= n; i++) {
                                                printf "%s%s", sep, name(ary[i]);
                                                sep = ";"
                                        }
                                }
                                printf ">";
                                $0 = substr($0, RSTART + RLENGTH, length($0) - RSTART - RLENGTH + 1);
                        }
                        print
                }
        '
}

nul_to_q () {
        perl -pe 'y/\000/Q/'
}

q_to_nul () {
        perl -pe 'y/Q/\000/'
}

q_to_cr () {
        tr Q '\015'
}

q_to_tab () {
        tr Q '\011'
}

append_cr () {
        sed -e 's/$/Q/' | tr Q '\015'
}

remove_cr () {
        tr '\015' Q | sed -e 's/Q$//'
}

# In some bourne shell implementations, the "unset" builtin returns
# nonzero status when a variable to be unset was not set in the first
# place.
#
# Use sane_unset when that should not be considered an error.

sane_unset () {
        unset "$@"
        return 0
}

test_tick () {
        if test -z "${test_tick+set}"
        then
                test_tick=1112911993
        else
                test_tick=$(($test_tick + 60))
        fi
        GIT_COMMITTER_DATE="$test_tick -0700"
        GIT_AUTHOR_DATE="$test_tick -0700"
        export GIT_COMMITTER_DATE GIT_AUTHOR_DATE
}

# Call test_commit with the arguments "<message> [<file> [<contents>]]"
#
# This will commit a file with the given contents and the given commit
# message.  It will also add a tag with <message> as name.
#
# Both <file> and <contents> default to <message>.

test_commit () {
        file=${2:-"$1.t"}
        echo "${3-$1}" > "$file" &&
        git add "$file" &&
        test_tick &&
        git commit -m "$1" &&
        git tag "$1"
}

# Call test_merge with the arguments "<message> <commit>", where <commit>
# can be a tag pointing to the commit-to-merge.

test_merge () {
        test_tick &&
        git merge -m "$1" "$2" &&
        git tag "$1"
}

# This function helps systems where core.filemode=false is set.
# Use it instead of plain 'chmod +x' to set or unset the executable bit
# of a file in the working directory and add it to the index.

test_chmod () {
        chmod "$@" &&
        git update-index --add "--chmod=$@"
}

# Unset a configuration variable, but don't fail if it doesn't exist.
test_unconfig () {
        git config --unset-all "$@"
        config_status=$?
        case "$config_status" in
        5) # ok, nothing to unset
                config_status=0
                ;;
        esac
        return $config_status
}

# Set git config, automatically unsetting it after the test is over.
test_config () {
        test_when_finished "test_unconfig '$1'" &&
        git config "$@"
}

# Use test_set_prereq to tell that a particular prerequisite is available.
# The prerequisite can later be checked for in two ways:
#
# - Explicitly using test_have_prereq.
#
# - Implicitly by specifying the prerequisite tag in the calls to
#   test_expect_{success,failure,code}.
#
# The single parameter is the prerequisite tag (a simple word, in all
# capital letters by convention).

test_set_prereq () {
        satisfied="$satisfied$1 "
}
satisfied=" "

test_have_prereq () {
        # prerequisites can be concatenated with ','
        save_IFS=$IFS
        IFS=,
        set -- $*
        IFS=$save_IFS

        total_prereq=0
        ok_prereq=0
        missing_prereq=

        for prerequisite
        do
                total_prereq=$(($total_prereq + 1))
                case $satisfied in
                *" $prerequisite "*)
                        ok_prereq=$(($ok_prereq + 1))
                        ;;
                *)
                        # Keep a list of missing prerequisites
                        if test -z "$missing_prereq"
                        then
                                missing_prereq=$prerequisite
                        else
                                missing_prereq="$prerequisite,$missing_prereq"
                        fi
                esac
        done

        test $total_prereq = $ok_prereq
}

test_declared_prereq () {
        case ",$test_prereq," in
        *,$1,*)
                return 0
                ;;
        esac
        return 1
}

# You are not expected to call test_ok_ and test_failure_ directly, use
# the text_expect_* functions instead.

test_ok_ () {
        test_success=$(($test_success + 1))
        say_color "" "ok $test_count - $@"
}

test_failure_ () {
        test_failure=$(($test_failure + 1))
        say_color error "not ok - $test_count $1"
        shift
        echo "$@" | sed -e 's/^/#       /'
        test "$immediate" = "" || { GIT_EXIT_OK=t; exit 1; }
}

test_known_broken_ok_ () {
        test_fixed=$(($test_fixed+1))
        say_color "" "ok $test_count - $@ # TODO known breakage"
}

test_known_broken_failure_ () {
        test_broken=$(($test_broken+1))
        say_color skip "not ok $test_count - $@ # TODO known breakage"
}

test_debug () {
        test "$debug" = "" || eval "$1"
}

test_eval_ () {
        # This is a separate function because some tests use
        # "return" to end a test_expect_success block early.
        eval >&3 2>&4 "$*"
}

test_run_ () {
        test_cleanup=:
        expecting_failure=$2
        test_eval_ "$1"
        eval_ret=$?

        if test -z "$immediate" || test $eval_ret = 0 || test -n "$expecting_failure"
        then
                test_eval_ "$test_cleanup"
        fi
        if test "$verbose" = "t" && test -n "$HARNESS_ACTIVE"; then
                echo ""
        fi
        return "$eval_ret"
}

test_skip () {
        test_count=$(($test_count+1))
        to_skip=
        for skp in $GIT_SKIP_TESTS
        do
                case $this_test.$test_count in
                $skp)
                        to_skip=t
                        break
                esac
        done
        if test -z "$to_skip" && test -n "$test_prereq" &&
           ! test_have_prereq "$test_prereq"
        then
                to_skip=t
        fi
        case "$to_skip" in
        t)
                of_prereq=
                if test "$missing_prereq" != "$test_prereq"
                then
                        of_prereq=" of $test_prereq"
                fi

                say_color skip >&3 "skipping test: $@"
                say_color skip "ok $test_count # skip $1 (missing $missing_prereq${of_prereq})"
                : true
                ;;
        *)
                false
                ;;
        esac
}

test_expect_failure () {
        test "$#" = 3 && { test_prereq=$1; shift; } || test_prereq=
        test "$#" = 2 ||
        error "bug in the test script: not 2 or 3 parameters to test-expect-failure"
        export test_prereq
        if ! test_skip "$@"
        then
                say >&3 "checking known breakage: $2"
                if test_run_ "$2" expecting_failure
                then
                        test_known_broken_ok_ "$1"
                else
                        test_known_broken_failure_ "$1"
                fi
        fi
        echo >&3 ""
}

test_expect_success () {
        test "$#" = 3 && { test_prereq=$1; shift; } || test_prereq=
        test "$#" = 2 ||
        error "bug in the test script: not 2 or 3 parameters to test-expect-success"
        export test_prereq
        if ! test_skip "$@"
        then
                say >&3 "expecting success: $2"
                if test_run_ "$2"
                then
                        test_ok_ "$1"
                else
                        test_failure_ "$@"
                fi
        fi
        echo >&3 ""
}

# test_external runs external test scripts that provide continuous
# test output about their progress, and succeeds/fails on
# zero/non-zero exit code.  It outputs the test output on stdout even
# in non-verbose mode, and announces the external script with "# run
# <n>: ..." before running it.  When providing relative paths, keep in
# mind that all scripts run in "trash directory".
# Usage: test_external description command arguments...
# Example: test_external 'Perl API' perl ../path/to/test.pl
test_external () {
        test "$#" = 4 && { test_prereq=$1; shift; } || test_prereq=
        test "$#" = 3 ||
        error >&5 "bug in the test script: not 3 or 4 parameters to test_external"
        descr="$1"
        shift
        export test_prereq
        if ! test_skip "$descr" "$@"
        then
                # Announce the script to reduce confusion about the
                # test output that follows.
                say_color "" "# run $test_count: $descr ($*)"
                # Export TEST_DIRECTORY, TRASH_DIRECTORY and GIT_TEST_LONG
                # to be able to use them in script
                export TEST_DIRECTORY TRASH_DIRECTORY GIT_TEST_LONG
                # Run command; redirect its stderr to &4 as in
                # test_run_, but keep its stdout on our stdout even in
                # non-verbose mode.
                "$@" 2>&4
                if [ "$?" = 0 ]
                then
                        if test $test_external_has_tap -eq 0; then
                                test_ok_ "$descr"
                        else
                                say_color "" "# test_external test $descr was ok"
                                test_success=$(($test_success + 1))
                        fi
                else
                        if test $test_external_has_tap -eq 0; then
                                test_failure_ "$descr" "$@"
                        else
                                say_color error "# test_external test $descr failed: $@"
                                test_failure=$(($test_failure + 1))
                        fi
                fi
        fi
}

# Like test_external, but in addition tests that the command generated
# no output on stderr.
test_external_without_stderr () {
        # The temporary file has no (and must have no) security
        # implications.
        tmp=${TMPDIR:-/tmp}
        stderr="$tmp/git-external-stderr.$$.tmp"
        test_external "$@" 4> "$stderr"
        [ -f "$stderr" ] || error "Internal error: $stderr disappeared."
        descr="no stderr: $1"
        shift
        say >&3 "# expecting no stderr from previous command"
        if [ ! -s "$stderr" ]; then
                rm "$stderr"

                if test $test_external_has_tap -eq 0; then
                        test_ok_ "$descr"
                else
                        say_color "" "# test_external_without_stderr test $descr was ok"
                        test_success=$(($test_success + 1))
                fi
        else
                if [ "$verbose" = t ]; then
                        output=`echo; echo "# Stderr is:"; cat "$stderr"`
                else
                        output=
                fi
                # rm first in case test_failure exits.
                rm "$stderr"
                if test $test_external_has_tap -eq 0; then
                        test_failure_ "$descr" "$@" "$output"
                else
                        say_color error "# test_external_without_stderr test $descr failed: $@: $output"
                        test_failure=$(($test_failure + 1))
                fi
        fi
}

# debugging-friendly alternatives to "test [-f|-d|-e]"
# The commands test the existence or non-existence of $1. $2 can be
# given to provide a more precise diagnosis.
test_path_is_file () {
        if ! [ -f "$1" ]
        then
                echo "File $1 doesn't exist. $*"
                false
        fi
}

test_path_is_dir () {
        if ! [ -d "$1" ]
        then
                echo "Directory $1 doesn't exist. $*"
                false
        fi
}

test_path_is_missing () {
        if [ -e "$1" ]
        then
                echo "Path exists:"
                ls -ld "$1"
                if [ $# -ge 1 ]; then
                        echo "$*"
                fi
                false
        fi
}

# test_line_count checks that a file has the number of lines it
# ought to. For example:
#
#       test_expect_success 'produce exactly one line of output' '
#               do something >output &&
#               test_line_count = 1 output
#       '
#
# is like "test $(wc -l <output) = 1" except that it passes the
# output through when the number of lines is wrong.

test_line_count () {
        if test $# != 3
        then
                error "bug in the test script: not 3 parameters to test_line_count"
        elif ! test $(wc -l <"$3") "$1" "$2"
        then
                echo "test_line_count: line count for $3 !$1 $2"
                cat "$3"
                return 1
        fi
}

# This is not among top-level (test_expect_success | test_expect_failure)
# but is a prefix that can be used in the test script, like:
#
#       test_expect_success 'complain and die' '
#           do something &&
#           do something else &&
#           test_must_fail git checkout ../outerspace
#       '
#
# Writing this as "! git checkout ../outerspace" is wrong, because
# the failure could be due to a segv.  We want a controlled failure.

test_must_fail () {
        "$@"
        exit_code=$?
        if test $exit_code = 0; then
                echo >&2 "test_must_fail: command succeeded: $*"
                return 1
        elif test $exit_code -gt 129 -a $exit_code -le 192; then
                echo >&2 "test_must_fail: died by signal: $*"
                return 1
        elif test $exit_code = 127; then
                echo >&2 "test_must_fail: command not found: $*"
                return 1
        fi
        return 0
}

# Similar to test_must_fail, but tolerates success, too.  This is
# meant to be used in contexts like:
#
#       test_expect_success 'some command works without configuration' '
#               test_might_fail git config --unset all.configuration &&
#               do something
#       '
#
# Writing "git config --unset all.configuration || :" would be wrong,
# because we want to notice if it fails due to segv.

test_might_fail () {
        "$@"
        exit_code=$?
        if test $exit_code -gt 129 -a $exit_code -le 192; then
                echo >&2 "test_might_fail: died by signal: $*"
                return 1
        elif test $exit_code = 127; then
                echo >&2 "test_might_fail: command not found: $*"
                return 1
        fi
        return 0
}

# Similar to test_must_fail and test_might_fail, but check that a
# given command exited with a given exit code. Meant to be used as:
#
#       test_expect_success 'Merge with d/f conflicts' '
#               test_expect_code 1 git merge "merge msg" B master
#       '

test_expect_code () {
        want_code=$1
        shift
        "$@"
        exit_code=$?
        if test $exit_code = $want_code
        then
                return 0
        fi

        echo >&2 "test_expect_code: command exited with $exit_code, we wanted $want_code $*"
        return 1
}

# test_cmp is a helper function to compare actual and expected output.
# You can use it like:
#
#       test_expect_success 'foo works' '
#               echo expected >expected &&
#               foo >actual &&
#               test_cmp expected actual
#       '
#
# This could be written as either "cmp" or "diff -u", but:
# - cmp's output is not nearly as easy to read as diff -u
# - not all diff versions understand "-u"

test_cmp() {
        $GIT_TEST_CMP "$@"
}

# This function can be used to schedule some commands to be run
# unconditionally at the end of the test to restore sanity:
#
#       test_expect_success 'test core.capslock' '
#               git config core.capslock true &&
#               test_when_finished "git config --unset core.capslock" &&
#               hello world
#       '
#
# That would be roughly equivalent to
#
#       test_expect_success 'test core.capslock' '
#               git config core.capslock true &&
#               hello world
#               git config --unset core.capslock
#       '
#
# except that the greeting and config --unset must both succeed for
# the test to pass.
#
# Note that under --immediate mode, no clean-up is done to help diagnose
# what went wrong.

test_when_finished () {
        test_cleanup="{ $*
                } && (exit \"\$eval_ret\"); eval_ret=\$?; $test_cleanup"
}

# Most tests can use the created repository, but some may need to create more.
# Usage: test_create_repo <directory>
test_create_repo () {
        test "$#" = 1 ||
        error "bug in the test script: not 1 parameter to test-create-repo"
        repo="$1"
        mkdir -p "$repo"
        (
                cd "$repo" || error "Cannot setup test environment"
                "$GIT_EXEC_PATH/git-init" "--template=$GIT_BUILD_DIR/templates/blt/" >&3 2>&4 ||
                error "cannot run git init -- have you built things yet?"
                mv .git/hooks .git/hooks-disabled
        ) || exit
}

test_done () {
        GIT_EXIT_OK=t

        if test -z "$HARNESS_ACTIVE"; then
                test_results_dir="$TEST_DIRECTORY/test-results"
                mkdir -p "$test_results_dir"
                test_results_path="$test_results_dir/${0%.sh}-$$.counts"

                cat >>"$test_results_path" <<-EOF
                total $test_count
                success $test_success
                fixed $test_fixed
                broken $test_broken
                failed $test_failure

                EOF
        fi

        if test "$test_fixed" != 0
        then
                say_color pass "# fixed $test_fixed known breakage(s)"
        fi
        if test "$test_broken" != 0
        then
                say_color error "# still have $test_broken known breakage(s)"
                msg="remaining $(($test_count-$test_broken)) test(s)"
        else
                msg="$test_count test(s)"
        fi
        case "$test_failure" in
        0)
                # Maybe print SKIP message
                [ -z "$skip_all" ] || skip_all=" # SKIP $skip_all"

                if test $test_external_has_tap -eq 0; then
                        say_color pass "# passed all $msg"
                        say "1..$test_count$skip_all"
                fi

                test -d "$remove_trash" &&
                cd "$(dirname "$remove_trash")" &&
                rm -rf "$(basename "$remove_trash")"

                exit 0 ;;

        *)
                if test $test_external_has_tap -eq 0; then
                        say_color error "# failed $test_failure among $msg"
                        say "1..$test_count"
                fi

                exit 1 ;;

        esac
}

# Test the binaries we have just built.  The tests are kept in
# t/ subdirectory and are run in 'trash directory' subdirectory.
if test -z "$TEST_DIRECTORY"
then
        # We allow tests to override this, in case they want to run tests
        # outside of t/, e.g. for running tests on the test library
        # itself.
        TEST_DIRECTORY=$(pwd)
fi
GIT_BUILD_DIR="$TEST_DIRECTORY"/..

if test -n "$valgrind"
then
        make_symlink () {
                test -h "$2" &&
                test "$1" = "$(readlink "$2")" || {
                        # be super paranoid
                        if mkdir "$2".lock
                        then
                                rm -f "$2" &&
                                ln -s "$1" "$2" &&
                                rm -r "$2".lock
                        else
                                while test -d "$2".lock
                                do
                                        say "Waiting for lock on $2."
                                        sleep 1
                                done
                        fi
                }
        }

        make_valgrind_symlink () {
                # handle only executables, unless they are shell libraries that
                # need to be in the exec-path.  We will just use "#!" as a
                # guess for a shell-script, since we have no idea what the user
                # may have configured as the shell path.
                test -x "$1" ||
                test "#!" = "$(head -c 2 <"$1")" ||
                return;

                base=$(basename "$1")
                symlink_target=$GIT_BUILD_DIR/$base
                # do not override scripts
                if test -x "$symlink_target" &&
                    test ! -d "$symlink_target" &&
                    test "#!" != "$(head -c 2 < "$symlink_target")"
                then
                        symlink_target=../valgrind.sh
                fi
                case "$base" in
                *.sh|*.perl)
                        symlink_target=../unprocessed-script
                esac
                # create the link, or replace it if it is out of date
                make_symlink "$symlink_target" "$GIT_VALGRIND/bin/$base" || exit
        }

        # override all git executables in TEST_DIRECTORY/..
        GIT_VALGRIND=$TEST_DIRECTORY/valgrind
        mkdir -p "$GIT_VALGRIND"/bin
        for file in $GIT_BUILD_DIR/git* $GIT_BUILD_DIR/test-*
        do
                make_valgrind_symlink $file
        done
        OLDIFS=$IFS
        IFS=:
        for path in $PATH
        do
                ls "$path"/git-* 2> /dev/null |
                while read file
                do
                        make_valgrind_symlink "$file"
                done
        done
        IFS=$OLDIFS
        PATH=$GIT_VALGRIND/bin:$PATH
        GIT_EXEC_PATH=$GIT_VALGRIND/bin
        export GIT_VALGRIND
elif test -n "$GIT_TEST_INSTALLED" ; then
        GIT_EXEC_PATH=$($GIT_TEST_INSTALLED/git --exec-path)  ||
        error "Cannot run git from $GIT_TEST_INSTALLED."
        PATH=$GIT_TEST_INSTALLED:$GIT_BUILD_DIR:$PATH
        GIT_EXEC_PATH=${GIT_TEST_EXEC_PATH:-$GIT_EXEC_PATH}
else # normal case, use ../bin-wrappers only unless $with_dashes:
        git_bin_dir="$GIT_BUILD_DIR/bin-wrappers"
        if ! test -x "$git_bin_dir/git" ; then
                if test -z "$with_dashes" ; then
                        say "$git_bin_dir/git is not executable; using GIT_EXEC_PATH"
                fi
                with_dashes=t
        fi
        PATH="$git_bin_dir:$PATH"
        GIT_EXEC_PATH=$GIT_BUILD_DIR
        if test -n "$with_dashes" ; then
                PATH="$GIT_BUILD_DIR:$PATH"
        fi
fi
GIT_TEMPLATE_DIR="$GIT_BUILD_DIR"/templates/blt
unset GIT_CONFIG
GIT_CONFIG_NOSYSTEM=1
GIT_ATTR_NOSYSTEM=1
export PATH GIT_EXEC_PATH GIT_TEMPLATE_DIR GIT_CONFIG_NOSYSTEM GIT_ATTR_NOSYSTEM

. "$GIT_BUILD_DIR"/GIT-BUILD-OPTIONS

if test -z "$GIT_TEST_CMP"
then
        if test -n "$GIT_TEST_CMP_USE_COPIED_CONTEXT"
        then
                GIT_TEST_CMP="$DIFF -c"
        else
                GIT_TEST_CMP="$DIFF -u"
        fi
fi

GITPERLLIB="$GIT_BUILD_DIR"/perl/blib/lib:"$GIT_BUILD_DIR"/perl/blib/arch/auto/Git
export GITPERLLIB
test -d "$GIT_BUILD_DIR"/templates/blt || {
        error "You haven't built things yet, have you?"
}

if test -z "$GIT_TEST_INSTALLED" && test -z "$NO_PYTHON"
then
        GITPYTHONLIB="$GIT_BUILD_DIR/git_remote_helpers/build/lib"
        export GITPYTHONLIB
        test -d "$GIT_BUILD_DIR"/git_remote_helpers/build || {
                error "You haven't built git_remote_helpers yet, have you?"
        }
fi

if ! test -x "$GIT_BUILD_DIR"/test-chmtime; then
        echo >&2 'You need to build test-chmtime:'
        echo >&2 'Run "make test-chmtime" in the source (toplevel) directory'
        exit 1
fi

# Test repository
test="trash directory.$(basename "$0" .sh)"
test -n "$root" && test="$root/$test"
case "$test" in
/*) TRASH_DIRECTORY="$test" ;;
 *) TRASH_DIRECTORY="$TEST_DIRECTORY/$test" ;;
esac
test ! -z "$debug" || remove_trash=$TRASH_DIRECTORY
rm -fr "$test" || {
        GIT_EXIT_OK=t
        echo >&5 "FATAL: Cannot prepare test area"
        exit 1
}

HOME="$TRASH_DIRECTORY"
export HOME

test_create_repo "$test"
# Use -P to resolve symlinks in our working directory so that the cwd
# in subprocesses like git equals our $PWD (for pathname comparisons).
cd -P "$test" || exit 1

this_test=${0##*/}
this_test=${this_test%%-*}
for skp in $GIT_SKIP_TESTS
do
        case "$this_test" in
        $skp)
                say_color skip >&3 "skipping test $this_test altogether"
                skip_all="skip all tests in $this_test"
                test_done
        esac
done

# Provide an implementation of the 'yes' utility
yes () {
        if test $# = 0
        then
                y=y
        else
                y="$*"
        fi

        while echo "$y"
        do
                :
        done
}

# Fix some commands on Windows
case $(uname -s) in
*MINGW*)
        # Windows has its own (incompatible) sort and find
        sort () {
                /usr/bin/sort "$@"
        }
        find () {
                /usr/bin/find "$@"
        }
        sum () {
                md5sum "$@"
        }
        # git sees Windows-style pwd
        pwd () {
                builtin pwd -W
        }
        # no POSIX permissions
        # backslashes in pathspec are converted to '/'
        # exec does not inherit the PID
        test_set_prereq MINGW
        test_set_prereq SED_STRIPS_CR
        ;;
*CYGWIN*)
        test_set_prereq POSIXPERM
        test_set_prereq EXECKEEPSPID
        test_set_prereq NOT_MINGW
        test_set_prereq SED_STRIPS_CR
        ;;
*)
        test_set_prereq POSIXPERM
        test_set_prereq BSLASHPSPEC
        test_set_prereq EXECKEEPSPID
        test_set_prereq NOT_MINGW
        ;;
esac

test -z "$NO_PERL" && test_set_prereq PERL
test -z "$NO_PYTHON" && test_set_prereq PYTHON
test -n "$USE_LIBPCRE" && test_set_prereq LIBPCRE

# Can we rely on git's output in the C locale?
if test -n "$GETTEXT_POISON"
then
        GIT_GETTEXT_POISON=YesPlease
        export GIT_GETTEXT_POISON
else
        test_set_prereq C_LOCALE_OUTPUT
fi

# Use this instead of test_cmp to compare files that contain expected and
# actual output from git commands that can be translated.  When running
# under GETTEXT_POISON this pretends that the command produced expected
# results.
test_i18ncmp () {
        test -n "$GETTEXT_POISON" || test_cmp "$@"
}

# Use this instead of "grep expected-string actual" to see if the
# output from a git command that can be translated either contains an
# expected string, or does not contain an unwanted one.  When running
# under GETTEXT_POISON this pretends that the command produced expected
# results.
test_i18ngrep () {
        if test -n "$GETTEXT_POISON"
        then
            : # pretend success
        elif test "x!" = "x$1"
        then
                shift
                ! grep "$@"
        else
                grep "$@"
        fi
}

# test whether the filesystem supports symbolic links
ln -s x y 2>/dev/null && test -h y 2>/dev/null && test_set_prereq SYMLINKS
rm -f y

# When the tests are run as root, permission tests will report that
# things are writable when they shouldn't be.
test -w / || test_set_prereq SANITY