# Test framework for git.  See t/README for usage.
#
# 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/ .

# 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)
else
        # ensure that TEST_DIRECTORY is an absolute path so that it
        # is valid even if the current working directory is changed
        TEST_DIRECTORY=$(cd "$TEST_DIRECTORY" && pwd) || exit 1
fi
if test -z "$TEST_OUTPUT_DIRECTORY"
then
        # Similarly, override this to store the test-results subdir
        # elsewhere
        TEST_OUTPUT_DIRECTORY=$TEST_DIRECTORY
fi
GIT_BUILD_DIR="$TEST_DIRECTORY"/..

# If we were built with ASAN, it may complain about leaks
# of program-lifetime variables. Disable it by default to lower
# the noise level. This needs to happen at the start of the script,
# before we even do our "did we build git yet" check (since we don't
# want that one to complain to stderr).
: ${ASAN_OPTIONS=detect_leaks=0:abort_on_error=1}
export ASAN_OPTIONS

# If LSAN is in effect we _do_ want leak checking, but we still
# want to abort so that we notice the problems.
: ${LSAN_OPTIONS=abort_on_error=1}
export LSAN_OPTIONS

################################################################
# It appears that people try to run tests without building...
"$GIT_BUILD_DIR/git" >/dev/null
if test $? != 1
then
        echo >&2 'error: you do not seem to have built git yet.'
        exit 1
fi

. "$GIT_BUILD_DIR"/GIT-BUILD-OPTIONS
export PERL_PATH SHELL_PATH

# 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, $* " in
done,*)
        # do not redirect again
        ;;
*' --tee '*|*' --va'*|*' --verbose-log '*)
        mkdir -p "$TEST_OUTPUT_DIRECTORY/test-results"
        BASE="$TEST_OUTPUT_DIRECTORY/test-results/$(basename "$0" .sh)"

        # Make this filename available to the sub-process in case it is using
        # --verbose-log.
        GIT_TEST_TEE_OUTPUT_FILE=$BASE.out
        export GIT_TEST_TEE_OUTPUT_FILE

        # Truncate before calling "tee -a" to get rid of the results
        # from any previous runs.
        >"$GIT_TEST_TEE_OUTPUT_FILE"

        (GIT_TEST_TEE_STARTED=done ${TEST_SHELL_PATH} "$0" "$@" 2>&1;
         echo $? >"$BASE.exit") | tee -a "$GIT_TEST_TEE_OUTPUT_FILE"
        test "$(cat "$BASE.exit")" = 0
        exit
        ;;
esac

# For repeatability, reset the environment to known value.
# TERM is sanitized below, after saving color control sequences.
LANG=C
LC_ALL=C
PAGER=cat
TZ=UTC
export LANG LC_ALL PAGER TZ
EDITOR=:
# A call to "unset" with no arguments causes at least Solaris 10
# /usr/xpg4/bin/sh and /bin/ksh to bail out.  So keep the unsets
# deriving from the command substitution clustered with the other
# ones.
unset VISUAL EMAIL LANGUAGE COLUMNS $("$PERL_PATH" -e '
        my @env = keys %ENV;
        my $ok = join("|", qw(
                TRACE
                DEBUG
                TEST
                .*_TEST
                PROVE
                VALGRIND
                UNZIP
                PERF_
                CURL_VERBOSE
                TRACE_CURL
        ));
        my @vars = grep(/^GIT_/ && !/^GIT_($ok)/o, @env);
        print join("\n", @vars);
')
unset XDG_CONFIG_HOME
unset GITPERLLIB
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
GIT_MERGE_AUTOEDIT=no
export GIT_MERGE_VERBOSITY GIT_MERGE_AUTOEDIT
export GIT_AUTHOR_EMAIL GIT_AUTHOR_NAME
export GIT_COMMITTER_EMAIL GIT_COMMITTER_NAME
export EDITOR

# Tests using GIT_TRACE typically don't want <timestamp> <file>:<line> output
GIT_TRACE_BARE=1
export GIT_TRACE_BARE

if test -n "${TEST_GIT_INDEX_VERSION:+isset}"
then
        GIT_INDEX_VERSION="$TEST_GIT_INDEX_VERSION"
        export GIT_INDEX_VERSION
fi

# Add libc MALLOC and MALLOC_PERTURB test
# only if we are not executing the test with valgrind
if expr " $GIT_TEST_OPTS " : ".* --valgrind " >/dev/null ||
   test -n "$TEST_NO_MALLOC_CHECK"
then
        setup_malloc_check () {
                : nothing
        }
        teardown_malloc_check () {
                : nothing
        }
else
        setup_malloc_check () {
                MALLOC_CHECK_=3 MALLOC_PERTURB_=165
                export MALLOC_CHECK_ MALLOC_PERTURB_
        }
        teardown_malloc_check () {
                unset MALLOC_CHECK_ MALLOC_PERTURB_
        }
fi

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

unset GREP_OPTIONS
unset UNZIP

case $(echo $GIT_TRACE |tr "[A-Z]" "[a-z]") in
1|2|true)
        GIT_TRACE=4
        ;;
esac

# Convenience
#
# A regexp to match 5, 35 and 40 hexdigits
_x05='[0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]'
_x35="$_x05$_x05$_x05$_x05$_x05$_x05$_x05"
_x40="$_x35$_x05"

# Zero SHA-1
_z40=0000000000000000000000000000000000000000

EMPTY_TREE=4b825dc642cb6eb9a060e54bf8d69288fbee4904
EMPTY_BLOB=e69de29bb2d1d6434b8b29ae775ad8c2e48c5391

# Line feed
LF='
'

# UTF-8 ZERO WIDTH NON-JOINER, which HFS+ ignores
# when case-folding filenames
u200c=$(printf '\342\200\214')

export _x05 _x35 _x40 _z40 LF u200c EMPTY_TREE EMPTY_BLOB

# 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
test "x$TERM" != "xdumb" && (
                test -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 "$1" in
        -d|--d|--de|--deb|--debu|--debug)
                debug=t; shift ;;
        -i|--i|--im|--imm|--imme|--immed|--immedi|--immedia|--immediat|--immediate)
                immediate=t; shift ;;
        -l|--l|--lo|--lon|--long|--long-|--long-t|--long-te|--long-tes|--long-test|--long-tests)
                GIT_TEST_LONG=t; export GIT_TEST_LONG; shift ;;
        -r)
                shift; test "$#" -ne 0 || {
                        echo 'error: -r requires an argument' >&2;
                        exit 1;
                }
                run_list=$1; shift ;;
        --run=*)
                run_list=${1#--*=}; shift ;;
        -h|--h|--he|--hel|--help)
                help=t; shift ;;
        -v|--v|--ve|--ver|--verb|--verbo|--verbos|--verbose)
                verbose=t; shift ;;
        --verbose-only=*)
                verbose_only=${1#--*=}
                shift ;;
        -q|--q|--qu|--qui|--quie|--quiet)
                # Ignore --quiet under a TAP::Harness. Saying how many tests
                # passed without the ok/not ok details is always an error.
                test -z "$HARNESS_ACTIVE" && quiet=t; shift ;;
        --with-dashes)
                with_dashes=t; shift ;;
        --no-color)
                color=; shift ;;
        --va|--val|--valg|--valgr|--valgri|--valgrin|--valgrind)
                valgrind=memcheck
                shift ;;
        --valgrind=*)
                valgrind=${1#--*=}
                shift ;;
        --valgrind-only=*)
                valgrind_only=${1#--*=}
                shift ;;
        --tee)
                shift ;; # was handled already
        --root=*)
                root=${1#--*=}
                shift ;;
        --chain-lint)
                GIT_TEST_CHAIN_LINT=1
                shift ;;
        --no-chain-lint)
                GIT_TEST_CHAIN_LINT=0
                shift ;;
        -x)
                # Some test scripts can't be reliably traced  with '-x',
                # unless the test is run with a Bash version supporting
                # BASH_XTRACEFD (introduced in Bash v4.1).  Check whether
                # this test is marked as such, and ignore '-x' if it
                # isn't executed with a suitable Bash version.
                if test -z "$test_untraceable" || {
                     test -n "$BASH_VERSION" && {
                       test ${BASH_VERSINFO[0]} -gt 4 || {
                         test ${BASH_VERSINFO[0]} -eq 4 &&
                         test ${BASH_VERSINFO[1]} -ge 1
                       }
                     }
                   }
                then
                        trace=t
                else
                        echo >&2 "warning: ignoring -x; '$0' is untraceable without BASH_XTRACEFD"
                fi
                shift ;;
        --verbose-log)
                verbose_log=t
                shift ;;
        *)
                echo "error: unknown test option '$1'" >&2; exit 1 ;;
        esac
done

if test -n "$valgrind_only"
then
        test -z "$valgrind" && valgrind=memcheck
        test -z "$verbose" && verbose_only="$valgrind_only"
elif test -n "$valgrind"
then
        test -z "$verbose_log" && verbose=t
fi

if test -n "$trace" && test -z "$verbose_log"
then
        verbose=t
fi

if test -n "$color"
then
        # Save the color control sequences now rather than run tput
        # each time say_color() is called.  This is done for two
        # reasons:
        #   * TERM will be changed to dumb
        #   * HOME will be changed to a temporary directory and tput
        #     might need to read ~/.terminfo from the original HOME
        #     directory to get the control sequences
        # Note:  This approach assumes the control sequences don't end
        # in a newline for any terminal of interest (command
        # substitutions strip trailing newlines).  Given that most
        # (all?) terminals in common use are related to ECMA-48, this
        # shouldn't be a problem.
        say_color_error=$(tput bold; tput setaf 1) # bold red
        say_color_skip=$(tput setaf 4) # blue
        say_color_warn=$(tput setaf 3) # brown/yellow
        say_color_pass=$(tput setaf 2) # green
        say_color_info=$(tput setaf 6) # cyan
        say_color_reset=$(tput sgr0)
        say_color_="" # no formatting for normal text
        say_color () {
                test -z "$1" && test -n "$quiet" && return
                eval "say_color_color=\$say_color_$1"
                shift
                printf "%s\\n" "$say_color_color$*$say_color_reset"
        }
else
        say_color() {
                test -z "$1" && test -n "$quiet" && return
                shift
                printf "%s\n" "$*"
        }
fi

TERM=dumb
export TERM

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

say () {
        say_color info "$*"
}

if test -n "$HARNESS_ACTIVE"
then
        if test "$verbose" = t || test -n "$verbose_only"
        then
                printf 'Bail out! %s\n' \
                 'verbose mode forbidden under TAP harness; try --verbose-log'
                exit 1
        fi
fi

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

if test "$help" = "t"
then
        printf '%s\n' "$test_description"
        exit 0
fi

exec 5>&1
exec 6<&0
exec 7>&2
if test "$verbose_log" = "t"
then
        exec 3>>"$GIT_TEST_TEE_OUTPUT_FILE" 4>&3
elif test "$verbose" = "t"
then
        exec 4>&2 3>&1
else
        exec 4>/dev/null 3>/dev/null
fi

# Send any "-x" output directly to stderr to avoid polluting tests
# which capture stderr. We can do this unconditionally since it
# has no effect if tracing isn't turned on.
#
# Note that this sets up the trace fd as soon as we assign the variable, so it
# must come after the creation of descriptor 4 above. Likewise, we must never
# unset this, as it has the side effect of closing descriptor 4, which we
# use to show verbose tests to the user.
#
# Note also that we don't need or want to export it. The tracing is local to
# this shell, and we would not want to influence any shells we exec.
BASH_XTRACEFD=4

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
trap 'exit $?' INT

# The user-facing functions are loaded from a separate file so that
# test_perf subshells can have them too
. "$TEST_DIRECTORY/test-lib-functions.sh"

# You are not expected to call test_ok_ and test_failure_ directly, use
# the test_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 - $1"
        shift
        printf '%s\n' "$*" | sed -e 's/^/#      /'
        test "$immediate" = "" || { GIT_EXIT_OK=t; exit 1; }
}

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

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

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

match_pattern_list () {
        arg="$1"
        shift
        test -z "$*" && return 1
        for pattern_
        do
                case "$arg" in
                $pattern_)
                        return 0
                esac
        done
        return 1
}

match_test_selector_list () {
        title="$1"
        shift
        arg="$1"
        shift
        test -z "$1" && return 0

        # Both commas and whitespace are accepted as separators.
        OLDIFS=$IFS
        IFS='   ,'
        set -- $1
        IFS=$OLDIFS

        # If the first selector is negative we include by default.
        include=
        case "$1" in
                !*) include=t ;;
        esac

        for selector
        do
                orig_selector=$selector

                positive=t
                case "$selector" in
                        !*)
                                positive=
                                selector=${selector##?}
                                ;;
                esac

                test -z "$selector" && continue

                case "$selector" in
                        *-*)
                                if expr "z${selector%%-*}" : "z[0-9]*[^0-9]" >/dev/null
                                then
                                        echo "error: $title: invalid non-numeric in range" \
                                                "start: '$orig_selector'" >&2
                                        exit 1
                                fi
                                if expr "z${selector#*-}" : "z[0-9]*[^0-9]" >/dev/null
                                then
                                        echo "error: $title: invalid non-numeric in range" \
                                                "end: '$orig_selector'" >&2
                                        exit 1
                                fi
                                ;;
                        *)
                                if expr "z$selector" : "z[0-9]*[^0-9]" >/dev/null
                                then
                                        echo "error: $title: invalid non-numeric in test" \
                                                "selector: '$orig_selector'" >&2
                                        exit 1
                                fi
                esac

                # Short cut for "obvious" cases
                test -z "$include" && test -z "$positive" && continue
                test -n "$include" && test -n "$positive" && continue

                case "$selector" in
                        -*)
                                if test $arg -le ${selector#-}
                                then
                                        include=$positive
                                fi
                                ;;
                        *-)
                                if test $arg -ge ${selector%-}
                                then
                                        include=$positive
                                fi
                                ;;
                        *-*)
                                if test ${selector%%-*} -le $arg \
                                        && test $arg -le ${selector#*-}
                                then
                                        include=$positive
                                fi
                                ;;
                        *)
                                if test $arg -eq $selector
                                then
                                        include=$positive
                                fi
                                ;;
                esac
        done

        test -n "$include"
}

maybe_teardown_verbose () {
        test -z "$verbose_only" && return
        exec 4>/dev/null 3>/dev/null
        verbose=
}

last_verbose=t
maybe_setup_verbose () {
        test -z "$verbose_only" && return
        if match_pattern_list $test_count $verbose_only
        then
                exec 4>&2 3>&1
                # Emit a delimiting blank line when going from
                # non-verbose to verbose.  Within verbose mode the
                # delimiter is printed by test_expect_*.  The choice
                # of the initial $last_verbose is such that before
                # test 1, we do not print it.
                test -z "$last_verbose" && echo >&3 ""
                verbose=t
        else
                exec 4>/dev/null 3>/dev/null
                verbose=
        fi
        last_verbose=$verbose
}

maybe_teardown_valgrind () {
        test -z "$GIT_VALGRIND" && return
        GIT_VALGRIND_ENABLED=
}

maybe_setup_valgrind () {
        test -z "$GIT_VALGRIND" && return
        if test -z "$valgrind_only"
        then
                GIT_VALGRIND_ENABLED=t
                return
        fi
        GIT_VALGRIND_ENABLED=
        if match_pattern_list $test_count $valgrind_only
        then
                GIT_VALGRIND_ENABLED=t
        fi
}

want_trace () {
        test "$trace" = t && {
                test "$verbose" = t || test "$verbose_log" = t
        }
}

# This is a separate function because some tests use
# "return" to end a test_expect_success block early
# (and we want to make sure we run any cleanup like
# "set +x").
test_eval_inner_ () {
        # Do not add anything extra (including LF) after '$*'
        eval "
                want_trace && set -x
                $*"
}

test_eval_ () {
        # If "-x" tracing is in effect, then we want to avoid polluting stderr
        # with non-test commands. But once in "set -x" mode, we cannot prevent
        # the shell from printing the "set +x" to turn it off (nor the saving
        # of $? before that). But we can make sure that the output goes to
        # /dev/null.
        #
        # There are a few subtleties here:
        #
        #   - we have to redirect descriptor 4 in addition to 2, to cover
        #     BASH_XTRACEFD
        #
        #   - the actual eval has to come before the redirection block (since
        #     it needs to see descriptor 4 to set up its stderr)
        #
        #   - likewise, any error message we print must be outside the block to
        #     access descriptor 4
        #
        #   - checking $? has to come immediately after the eval, but it must
        #     be _inside_ the block to avoid polluting the "set -x" output
        #

        test_eval_inner_ "$@" </dev/null >&3 2>&4
        {
                test_eval_ret_=$?
                if want_trace
                then
                        set +x
                fi
        } 2>/dev/null 4>&2

        if test "$test_eval_ret_" != 0 && want_trace
        then
                say_color error >&4 "error: last command exited with \$?=$test_eval_ret_"
        fi
        return $test_eval_ret_
}

test_run_ () {
        test_cleanup=:
        expecting_failure=$2

        if test "${GIT_TEST_CHAIN_LINT:-1}" != 0; then
                # turn off tracing for this test-eval, as it simply creates
                # confusing noise in the "-x" output
                trace_tmp=$trace
                trace=
                # 117 is magic because it is unlikely to match the exit
                # code of other programs
                if test "OK-117" != "$(test_eval_ "(exit 117) && $1${LF}${LF}echo OK-\$?" 3>&1)"
                then
                        error "bug in the test script: broken &&-chain or run-away HERE-DOC: $1"
                fi
                trace=$trace_tmp
        fi

        setup_malloc_check
        test_eval_ "$1"
        eval_ret=$?
        teardown_malloc_check

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

test_start_ () {
        test_count=$(($test_count+1))
        maybe_setup_verbose
        maybe_setup_valgrind
}

test_finish_ () {
        echo >&3 ""
        maybe_teardown_valgrind
        maybe_teardown_verbose
}

test_skip () {
        to_skip=
        skipped_reason=
        if match_pattern_list $this_test.$test_count $GIT_SKIP_TESTS
        then
                to_skip=t
                skipped_reason="GIT_SKIP_TESTS"
        fi
        if test -z "$to_skip" && test -n "$test_prereq" &&
           ! test_have_prereq "$test_prereq"
        then
                to_skip=t

                of_prereq=
                if test "$missing_prereq" != "$test_prereq"
                then
                        of_prereq=" of $test_prereq"
                fi
                skipped_reason="missing $missing_prereq${of_prereq}"
        fi
        if test -z "$to_skip" && test -n "$run_list" &&
                ! match_test_selector_list '--run' $test_count "$run_list"
        then
                to_skip=t
                skipped_reason="--run"
        fi

        case "$to_skip" in
        t)
                say_color skip >&3 "skipping test: $@"
                say_color skip "ok $test_count # skip $1 ($skipped_reason)"
                : true
                ;;
        *)
                false
                ;;
        esac
}

# stub; perf-lib overrides it
test_at_end_hook_ () {
        :
}

test_done () {
        GIT_EXIT_OK=t

        if test -z "$HARNESS_ACTIVE"
        then
                test_results_dir="$TEST_OUTPUT_DIRECTORY/test-results"
                mkdir -p "$test_results_dir"
                base=${0##*/}
                test_results_path="$test_results_dir/${base%.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 error "# $test_fixed known breakage(s) vanished; please update test(s)"
        fi
        if test "$test_broken" != 0
        then
                say_color warn "# still have $test_broken known breakage(s)"
        fi
        if test "$test_broken" != 0 || test "$test_fixed" != 0
        then
                test_remaining=$(( $test_count - $test_broken - $test_fixed ))
                msg="remaining $test_remaining test(s)"
        else
                test_remaining=$test_count
                msg="$test_count test(s)"
        fi
        case "$test_failure" in
        0)
                if test $test_external_has_tap -eq 0
                then
                        if test $test_remaining -gt 0
                        then
                                say_color pass "# passed all $msg"
                        fi

                        # Maybe print SKIP message
                        test -z "$skip_all" || skip_all="# SKIP $skip_all"
                        case "$test_count" in
                        0)
                                say "1..$test_count${skip_all:+ $skip_all}"
                                ;;
                        *)
                                test -z "$skip_all" ||
                                say_color warn "$skip_all"
                                say "1..$test_count"
                                ;;
                        esac
                fi

                if test -z "$debug"
                then
                        test -d "$TRASH_DIRECTORY" ||
                        error "Tests passed but trash directory already removed before test cleanup; aborting"

                        cd "$TRASH_DIRECTORY/.." &&
                        rm -fr "$TRASH_DIRECTORY" ||
                        error "Tests passed but test cleanup failed; aborting"
                fi
                test_at_end_hook_

                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
}

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.
                test -x "$1" ||
                test "# " = "$(head -c 2 <"$1")" ||
                return;

                base=$(basename "$1")
                case "$base" in
                test-*)
                        symlink_target="$GIT_BUILD_DIR/t/helper/$base"
                        ;;
                *)
                        symlink_target="$GIT_BUILD_DIR/$base"
                        ;;
                esac
                # 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/t/helper/test-*
        do
                make_valgrind_symlink $file
        done
        # special-case the mergetools loadables
        make_symlink "$GIT_BUILD_DIR"/mergetools "$GIT_VALGRIND/bin/mergetools"
        OLDIFS=$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=$GIT_VALGRIND/bin
        export GIT_VALGRIND
        GIT_VALGRIND_MODE="$valgrind"
        export GIT_VALGRIND_MODE
        GIT_VALGRIND_ENABLED=t
        test -n "$valgrind_only" && GIT_VALGRIND_ENABLED=
        export GIT_VALGRIND_ENABLED
elif test -n "$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
GIT_CONFIG_NOSYSTEM=1
GIT_ATTR_NOSYSTEM=1
export PATH GIT_EXEC_PATH GIT_TEMPLATE_DIR GIT_CONFIG_NOSYSTEM GIT_ATTR_NOSYSTEM

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

if ! test -x "$GIT_BUILD_DIR"/t/helper/test-chmtime
then
        echo >&2 'You need to build test-chmtime:'
        echo >&2 'Run "make t/helper/test-chmtime" in the source (toplevel) directory'
        exit 1
fi

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

HOME="$TRASH_DIRECTORY"
GNUPGHOME="$HOME/gnupg-home-not-used"
export HOME GNUPGHOME

if test -z "$TEST_NO_CREATE_REPO"
then
        test_create_repo "$TRASH_DIRECTORY"
else
        mkdir -p "$TRASH_DIRECTORY"
fi
# Use -P to resolve symlinks in our working directory so that the cwd
# in subprocesses like git equals our $PWD (for pathname comparisons).
cd -P "$TRASH_DIRECTORY" || exit 1

this_test=${0##*/}
this_test=${this_test%%-*}
if match_pattern_list "$this_test" $GIT_SKIP_TESTS
then
        say_color info >&3 "skipping test $this_test altogether"
        skip_all="skip all tests in $this_test"
        test_done
fi

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

        i=0
        while test $i -lt 99
        do
                echo "$y"
                i=$(($i+1))
        done
}

# Fix some commands on Windows
uname_s=$(uname -s)
case $uname_s in
*MINGW*)
        # Windows has its own (incompatible) sort and find
        sort () {
                /usr/bin/sort "$@"
        }
        find () {
                /usr/bin/find "$@"
        }
        # 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 NATIVE_CRLF
        test_set_prereq SED_STRIPS_CR
        test_set_prereq GREP_STRIPS_CR
        GIT_TEST_CMP=mingw_test_cmp
        ;;
*CYGWIN*)
        test_set_prereq POSIXPERM
        test_set_prereq EXECKEEPSPID
        test_set_prereq CYGWIN
        test_set_prereq SED_STRIPS_CR
        test_set_prereq GREP_STRIPS_CR
        ;;
*)
        test_set_prereq POSIXPERM
        test_set_prereq BSLASHPSPEC
        test_set_prereq EXECKEEPSPID
        ;;
esac

( COLUMNS=1 && test $COLUMNS = 1 ) && test_set_prereq COLUMNS_CAN_BE_1
test -z "$NO_PERL" && test_set_prereq PERL
test -z "$NO_PTHREADS" && test_set_prereq PTHREADS
test -z "$NO_PYTHON" && test_set_prereq PYTHON
test -n "$USE_LIBPCRE1$USE_LIBPCRE2" && test_set_prereq PCRE
test -n "$USE_LIBPCRE1" && test_set_prereq LIBPCRE1
test -n "$USE_LIBPCRE2" && test_set_prereq LIBPCRE2
test -z "$NO_GETTEXT" && test_set_prereq GETTEXT

# 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
        test_set_prereq GETTEXT_POISON
else
        test_set_prereq C_LOCALE_OUTPUT
fi

test_lazy_prereq PIPE '
        # test whether the filesystem supports FIFOs
        test_have_prereq !MINGW,!CYGWIN &&
        rm -f testfifo && mkfifo testfifo
'

test_lazy_prereq SYMLINKS '
        # test whether the filesystem supports symbolic links
        ln -s x y && test -h y
'

test_lazy_prereq FILEMODE '
        test "$(git config --bool core.filemode)" = true
'

test_lazy_prereq CASE_INSENSITIVE_FS '
        echo good >CamelCase &&
        echo bad >camelcase &&
        test "$(cat CamelCase)" != good
'

test_lazy_prereq UTF8_NFD_TO_NFC '
        # check whether FS converts nfd unicode to nfc
        auml=$(printf "\303\244")
        aumlcdiar=$(printf "\141\314\210")
        >"$auml" &&
        case "$(echo *)" in
        "$aumlcdiar")
                true ;;
        *)
                false ;;
        esac
'

test_lazy_prereq AUTOIDENT '
        sane_unset GIT_AUTHOR_NAME &&
        sane_unset GIT_AUTHOR_EMAIL &&
        git var GIT_AUTHOR_IDENT
'

test_lazy_prereq EXPENSIVE '
        test -n "$GIT_TEST_LONG"
'

test_lazy_prereq EXPENSIVE_ON_WINDOWS '
        test_have_prereq EXPENSIVE || test_have_prereq !MINGW,!CYGWIN
'

test_lazy_prereq USR_BIN_TIME '
        test -x /usr/bin/time
'

test_lazy_prereq NOT_ROOT '
        uid=$(id -u) &&
        test "$uid" != 0
'

test_lazy_prereq JGIT '
        type jgit
'

# SANITY is about "can you correctly predict what the filesystem would
# do by only looking at the permission bits of the files and
# directories?"  A typical example of !SANITY is running the test
# suite as root, where a test may expect "chmod -r file && cat file"
# to fail because file is supposed to be unreadable after a successful
# chmod.  In an environment (i.e. combination of what filesystem is
# being used and who is running the tests) that lacks SANITY, you may
# be able to delete or create a file when the containing directory
# doesn't have write permissions, or access a file even if the
# containing directory doesn't have read or execute permissions.

test_lazy_prereq SANITY '
        mkdir SANETESTD.1 SANETESTD.2 &&

        chmod +w SANETESTD.1 SANETESTD.2 &&
        >SANETESTD.1/x 2>SANETESTD.2/x &&
        chmod -w SANETESTD.1 &&
        chmod -r SANETESTD.1/x &&
        chmod -rx SANETESTD.2 ||
        error "bug in test sript: cannot prepare SANETESTD"

        ! test -r SANETESTD.1/x &&
        ! rm SANETESTD.1/x && ! test -f SANETESTD.2/x
        status=$?

        chmod +rwx SANETESTD.1 SANETESTD.2 &&
        rm -rf SANETESTD.1 SANETESTD.2 ||
        error "bug in test sript: cannot clean SANETESTD"
        return $status
'

test FreeBSD != $uname_s || GIT_UNZIP=${GIT_UNZIP:-/usr/local/bin/unzip}
GIT_UNZIP=${GIT_UNZIP:-unzip}
test_lazy_prereq UNZIP '
        "$GIT_UNZIP" -v
        test $? -ne 127
'

run_with_limited_cmdline () {
        (ulimit -s 128 && "$@")
}

test_lazy_prereq CMDLINE_LIMIT '
        test_have_prereq !MINGW,!CYGWIN &&
        run_with_limited_cmdline true
'

run_with_limited_stack () {
        (ulimit -s 128 && "$@")
}

test_lazy_prereq ULIMIT_STACK_SIZE '
        test_have_prereq !MINGW,!CYGWIN &&
        run_with_limited_stack true
'

build_option () {
        git version --build-options |
        sed -ne "s/^$1: //p"
}

test_lazy_prereq LONG_IS_64BIT '
        test 8 -le "$(build_option sizeof-long)"
'

test_lazy_prereq TIME_IS_64BIT 'test-date is64bit'
test_lazy_prereq TIME_T_IS_64BIT 'test-date time_t-is64bit'