t/test-lib-functions.sh - git - Git at Google

 # Library of functions shared by all tests scripts, included by
 # test-lib.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/ .

 # 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_set_index_version () {
     GIT_INDEX_VERSION="$1"
     export GIT_INDEX_VERSION
 }

 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'
 }

 qz_to_tab_space () {
 	tr QZ '\011\040'
 }

 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
 }

 # Stop execution and start a shell. This is useful for debugging tests and
 # only makes sense together with "-v".
 #
 # Be sure to remove all invocations of this command before submitting.

 test_pause () {
 	if test "$verbose" = t; then
 		"$SHELL_PATH" <&6 >&3 2>&4
 	else
 		error >&5 "test_pause requires --verbose"
 	fi
 }

 # Call test_commit with the arguments "<message> [<file> [<contents> [<tag>]]]"
 #
 # This will commit a file with the given contents and the given commit
 # message, and tag the resulting commit with the given tag name.
 #
 # <file>, <contents>, and <tag> all default to <message>.

 test_commit () {
 	notick= &&
 	signoff= &&
 	while test $# != 0
 	do
 		case "$1" in
 		--notick)
 			notick=yes
 			;;
 		--signoff)
 			signoff="$1"
 			;;
 		*)
 			break
 			;;
 		esac
 		shift
 	done &&
 	file=${2:-"$1.t"} &&
 	echo "${3-$1}" > "$file" &&
 	git add "$file" &&
 	if test -z "$notick"
 	then
 		test_tick
 	fi &&
 	git commit $signoff -m "$1" &&
 	git tag "${4:-$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 '$1'" &&
 	git config "$@"
 }

 test_config_global () {
 	test_when_finished "test_unconfig --global '$1'" &&
 	git config --global "$@"
 }

 write_script () {
 	{
 		echo "#!${2-"$SHELL_PATH"}" &&
 		cat
 	} >"$1" &&
 	chmod +x "$1"
 }

 # 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_prereq="$satisfied_prereq$1 "
 }
 satisfied_prereq=" "
 lazily_testable_prereq= lazily_tested_prereq=

 # Usage: test_lazy_prereq PREREQ 'script'
 test_lazy_prereq () {
 	lazily_testable_prereq="$lazily_testable_prereq$1 "
 	eval test_prereq_lazily_$1=\$2
 }

 test_run_lazy_prereq_ () {
 	script='
 mkdir -p "$TRASH_DIRECTORY/prereq-test-dir" &&
 (
 	cd "$TRASH_DIRECTORY/prereq-test-dir" &&'"$2"'
 )'
 	say >&3 "checking prerequisite: $1"
 	say >&3 "$script"
 	test_eval_ "$script"
 	eval_ret=$?
 	rm -rf "$TRASH_DIRECTORY/prereq-test-dir"
 	if test "$eval_ret" = 0; then
 		say >&3 "prerequisite $1 ok"
 	else
 		say >&3 "prerequisite $1 not satisfied"
 	fi
 	return $eval_ret
 }

 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
 		case "$prerequisite" in
 		!*)
 			negative_prereq=t
 			prerequisite=${prerequisite#!}
 			;;
 		*)
 			negative_prereq=
 		esac

 		case " $lazily_tested_prereq " in
 		*" $prerequisite "*)
 			;;
 		*)
 			case " $lazily_testable_prereq " in
 			*" $prerequisite "*)
 				eval "script=\$test_prereq_lazily_$prerequisite" &&
 				if test_run_lazy_prereq_ "$prerequisite" "$script"
 				then
 					test_set_prereq $prerequisite
 				fi
 				lazily_tested_prereq="$lazily_tested_prereq$prerequisite "
 			esac
 			;;
 		esac

 		total_prereq=$(($total_prereq + 1))
 		case "$satisfied_prereq" in
 		*" $prerequisite "*)
 			satisfied_this_prereq=t
 			;;
 		*)
 			satisfied_this_prereq=
 		esac

 		case "$satisfied_this_prereq,$negative_prereq" in
 		t,|,t)
 			ok_prereq=$(($ok_prereq + 1))
 			;;
 		*)
 			# Keep a list of missing prerequisites; restore
 			# the negative marker if necessary.
 			prerequisite=${negative_prereq:+!}$prerequisite
 			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
 }

 test_expect_failure () {
 	test_start_
 	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
 	test_finish_
 }

 test_expect_success () {
 	test_start_
 	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
 	test_finish_
 }

 # 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.
 		"$@" 2>&4
 		if test "$?" = 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"
 	test -f "$stderr" || error "Internal error: $stderr disappeared."
 	descr="no stderr: $1"
 	shift
 	say >&3 "# expecting no stderr from previous command"
 	if test ! -s "$stderr"
 	then
 		rm "$stderr"

 		if test $test_external_has_tap -eq 0; then
 			test_ok_ "$descr"
 		else
 			say_color "" "# test_external_without_stderr test $descr was ok"
 			test_success=$(($test_success + 1))
 		fi
 	else
 		if test "$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 ! test -f "$1"
 	then
 		echo "File $1 doesn't exist. $*"
 		false
 	fi
 }

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

 # Check if the directory exists and is empty as expected, barf otherwise.
 test_dir_is_empty () {
 	test_path_is_dir "$1" &&
 	if test -n "$(ls -a1 "$1" | egrep -v '^\.\.?$')"
 	then
 		echo "Directory '$1' is not empty, it contains:"
 		ls -la "$1"
 		return 1
 	fi
 }

 test_path_is_missing () {
 	if test -e "$1"
 	then
 		echo "Path exists:"
 		ls -ld "$1"
 		if test $# -ge 1
 		then
 			echo "$*"
 		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 && test $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
 	elif test $exit_code = 126; then
 		echo >&2 "test_must_fail: valgrind error: $*"
 		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 && test $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() {
 	$GIT_TEST_CMP "$@"
 }

 # test_cmp_bin - helper to compare binary files

 test_cmp_bin() {
 	cmp "$@"
 }

 # Call any command "$@" but be more verbose about its
 # failure. This is handy for commands like "test" which do
 # not output anything when they fail.
 verbose () {
 	"$@" && return 0
 	echo >&2 "command failed: $(git rev-parse --sq-quote "$@")"
 	return 1
 }

 # Check if the file expected to be empty is indeed empty, and barfs
 # otherwise.

 test_must_be_empty () {
 	if test -s "$1"
 	then
 		echo "'$1' is not empty, it contains:"
 		cat "$1"
 		return 1
 	fi
 }

 # Tests that its two parameters refer to the same revision
 test_cmp_rev () {
 	git rev-parse --verify "$1" >expect.rev &&
 	git rev-parse --verify "$2" >actual.rev &&
 	test_cmp expect.rev actual.rev
 }

 # Print a sequence of numbers or letters in increasing order.  This is
 # similar to GNU seq(1), but the latter might not be available
 # everywhere (and does not do letters).  It may be used like:
 #
 #	for i in $(test_seq 100)
 #	do
 #		for j in $(test_seq 10 20)
 #		do
 #			for k in $(test_seq a z)
 #			do
 #				echo $i-$j-$k
 #			done
 #		done
 #	done

 test_seq () {
 	case $# in
 	1)	set 1 "$@" ;;
 	2)	;;
 	*)	error "bug in the test script: not 1 or 2 parameters to test_seq" ;;
 	esac
 	perl -le 'print for $ARGV[0]..$ARGV[1]' -- "$@"
 }

 # 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
 }

 # This function helps on symlink challenged file systems when it is not
 # important that the file system entry is a symbolic link.
 # Use test_ln_s_add instead of "ln -s x y && git add y" to add a
 # symbolic link entry y to the index.

 test_ln_s_add () {
 	if test_have_prereq SYMLINKS
 	then
 		ln -s "$1" "$2" &&
 		git update-index --add "$2"
 	else
 		printf '%s' "$1" >"$2" &&
 		ln_s_obj=$(git hash-object -w "$2") &&
 		git update-index --add --cacheinfo 120000 $ln_s_obj "$2"
 	fi
 }

 # This function writes out its parameters, one per line
 test_write_lines () {
 	printf "%s\n" "$@"
 }

 perl () {
 	command "$PERL_PATH" "$@"
 }

 # Is the value one of the various ways to spell a boolean true/false?
 test_normalize_bool () {
 	git -c magic.variable="$1" config --bool magic.variable 2>/dev/null
 }

 # Given a variable $1, normalize the value of it to one of "true",
 # "false", or "auto" and store the result to it.
 #
 #     test_tristate GIT_TEST_HTTPD
 #
 # A variable set to an empty string is set to 'false'.
 # A variable set to 'false' or 'auto' keeps its value.
 # Anything else is set to 'true'.
 # An unset variable defaults to 'auto'.
 #
 # The last rule is to allow people to set the variable to an empty
 # string and export it to decline testing the particular feature
 # for versions both before and after this change.  We used to treat
 # both unset and empty variable as a signal for "do not test" and
 # took any non-empty string as "please test".

 test_tristate () {
 	if eval "test x\"\${$1+isset}\" = xisset"
 	then
 		# explicitly set
 		eval "
 			case \"\$$1\" in
 			'')	$1=false ;;
 			auto)	;;
 			*)	$1=\$(test_normalize_bool \$$1 || echo true) ;;
 			esac
 		"
 	else
 		eval "$1=auto"
 	fi
 }

 # Exit the test suite, either by skipping all remaining tests or by
 # exiting with an error. If "$1" is "auto", we then we assume we were
 # opportunistically trying to set up some tests and we skip. If it is
 # "true", then we report a failure.
 #
 # The error/skip message should be given by $2.
 #
 test_skip_or_die () {
 	case "$1" in
 	auto)
 		skip_all=$2
 		test_done
 		;;
 	true)
 		error "$2"
 		;;
 	*)
 		error "BUG: test tristate is '$1' (real error: $2)"
 	esac
 }

 # The following mingw_* functions obey POSIX shell syntax, but are actually
 # bash scripts, and are meant to be used only with bash on Windows.

 # A test_cmp function that treats LF and CRLF equal and avoids to fork
 # diff when possible.
 mingw_test_cmp () {
 	# Read text into shell variables and compare them. If the results
 	# are different, use regular diff to report the difference.
 	local test_cmp_a= test_cmp_b=

 	# When text came from stdin (one argument is '-') we must feed it
 	# to diff.
 	local stdin_for_diff=

 	# Since it is difficult to detect the difference between an
 	# empty input file and a failure to read the files, we go straight
 	# to diff if one of the inputs is empty.
 	if test -s "$1" && test -s "$2"
 	then
 		# regular case: both files non-empty
 		mingw_read_file_strip_cr_ test_cmp_a <"$1"
 		mingw_read_file_strip_cr_ test_cmp_b <"$2"
 	elif test -s "$1" && test "$2" = -
 	then
 		# read 2nd file from stdin
 		mingw_read_file_strip_cr_ test_cmp_a <"$1"
 		mingw_read_file_strip_cr_ test_cmp_b
 		stdin_for_diff='<<<"$test_cmp_b"'
 	elif test "$1" = - && test -s "$2"
 	then
 		# read 1st file from stdin
 		mingw_read_file_strip_cr_ test_cmp_a
 		mingw_read_file_strip_cr_ test_cmp_b <"$2"
 		stdin_for_diff='<<<"$test_cmp_a"'
 	fi
 	test -n "$test_cmp_a" &&
 	test -n "$test_cmp_b" &&
 	test "$test_cmp_a" = "$test_cmp_b" ||
 	eval "diff -u \"\$@\" $stdin_for_diff"
 }

 # $1 is the name of the shell variable to fill in
 mingw_read_file_strip_cr_ () {
 	# Read line-wise using LF as the line separator
 	# and use IFS to strip CR.
 	local line
 	while :
 	do
 		if IFS=$'\r' read -r -d $'\n' line
 		then
 			# good
 			line=$line$'\n'
 		else
 			# we get here at EOF, but also if the last line
 			# was not terminated by LF; in the latter case,
 			# some text was read
 			if test -z "$line"
 			then
 				# EOF, really
 				break
 			fi
 		fi
 		eval "$1=\$$1\$line"
 	done
 }
	# Library of functions shared by all tests scripts, included by
	# test-lib.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/ .

	# 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_set_index_version () {
	GIT_INDEX_VERSION="$1"
	export GIT_INDEX_VERSION
	}

	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'
	}

	qz_to_tab_space () {
	tr QZ '\011\040'
	}

	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
	}

	# Stop execution and start a shell. This is useful for debugging tests and
	# only makes sense together with "-v".
	#
	# Be sure to remove all invocations of this command before submitting.

	test_pause () {
	if test "$verbose" = t; then
	"$SHELL_PATH" <&6 >&3 2>&4
	else
	error >&5 "test_pause requires --verbose"
	fi
	}

	# Call test_commit with the arguments "<message> [<file> [<contents> [<tag>]]]"
	#
	# This will commit a file with the given contents and the given commit
	# message, and tag the resulting commit with the given tag name.
	#
	# <file>, <contents>, and <tag> all default to <message>.

	test_commit () {
	notick= &&
	signoff= &&
	while test $# != 0
	do
	case "$1" in
	--notick)
	notick=yes
	;;
	--signoff)
	signoff="$1"
	;;
	*)
	break
	;;
	esac
	shift
	done &&
	file=${2:-"$1.t"} &&
	echo "${3-$1}" > "$file" &&
	git add "$file" &&
	if test -z "$notick"
	then
	test_tick
	fi &&
	git commit $signoff -m "$1" &&
	git tag "${4:-$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 '$1'" &&
	git config "$@"
	}

	test_config_global () {
	test_when_finished "test_unconfig --global '$1'" &&
	git config --global "$@"
	}

	write_script () {
	{
	echo "#!${2-"$SHELL_PATH"}" &&
	cat
	} >"$1" &&
	chmod +x "$1"
	}

	# 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_prereq="$satisfied_prereq$1 "
	}
	satisfied_prereq=" "
	lazily_testable_prereq= lazily_tested_prereq=

	# Usage: test_lazy_prereq PREREQ 'script'
	test_lazy_prereq () {
	lazily_testable_prereq="$lazily_testable_prereq$1 "
	eval test_prereq_lazily_$1=\$2
	}

	test_run_lazy_prereq_ () {
	script='
	mkdir -p "$TRASH_DIRECTORY/prereq-test-dir" &&
	(
	cd "$TRASH_DIRECTORY/prereq-test-dir" &&'"$2"'
	)'
	say >&3 "checking prerequisite: $1"
	say >&3 "$script"
	test_eval_ "$script"
	eval_ret=$?
	rm -rf "$TRASH_DIRECTORY/prereq-test-dir"
	if test "$eval_ret" = 0; then
	say >&3 "prerequisite $1 ok"
	else
	say >&3 "prerequisite $1 not satisfied"
	fi
	return $eval_ret
	}

	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
	case "$prerequisite" in
	!*)
	negative_prereq=t
	prerequisite=${prerequisite#!}
	;;
	*)
	negative_prereq=
	esac

	case " $lazily_tested_prereq " in
	" $prerequisite ")
	;;
	*)
	case " $lazily_testable_prereq " in
	" $prerequisite ")
	eval "script=\$test_prereq_lazily_$prerequisite" &&
	if test_run_lazy_prereq_ "$prerequisite" "$script"
	then
	test_set_prereq $prerequisite
	fi
	lazily_tested_prereq="$lazily_tested_prereq$prerequisite "
	esac
	;;
	esac

	total_prereq=$(($total_prereq + 1))
	case "$satisfied_prereq" in
	" $prerequisite ")
	satisfied_this_prereq=t
	;;
	*)
	satisfied_this_prereq=
	esac

	case "$satisfied_this_prereq,$negative_prereq" in
	t,\|,t)
	ok_prereq=$(($ok_prereq + 1))
	;;
	*)
	# Keep a list of missing prerequisites; restore
	# the negative marker if necessary.
	prerequisite=${negative_prereq:+!}$prerequisite
	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
	}

	test_expect_failure () {
	test_start_
	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
	test_finish_
	}

	test_expect_success () {
	test_start_
	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
	test_finish_
	}

	# 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.
	"$@" 2>&4
	if test "$?" = 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"
	test -f "$stderr" \|\| error "Internal error: $stderr disappeared."
	descr="no stderr: $1"
	shift
	say >&3 "# expecting no stderr from previous command"
	if test ! -s "$stderr"
	then
	rm "$stderr"

	if test $test_external_has_tap -eq 0; then
	test_ok_ "$descr"
	else
	say_color "" "# test_external_without_stderr test $descr was ok"
	test_success=$(($test_success + 1))
	fi
	else
	if test "$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 ! test -f "$1"
	then
	echo "File $1 doesn't exist. $*"
	false
	fi
	}

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

	# Check if the directory exists and is empty as expected, barf otherwise.
	test_dir_is_empty () {
	test_path_is_dir "$1" &&
	if test -n "$(ls -a1 "$1" \| egrep -v '^\.\.?$')"
	then
	echo "Directory '$1' is not empty, it contains:"
	ls -la "$1"
	return 1
	fi
	}

	test_path_is_missing () {
	if test -e "$1"
	then
	echo "Path exists:"
	ls -ld "$1"
	if test $# -ge 1
	then
	echo "$*"
	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 && test $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
	elif test $exit_code = 126; then
	echo >&2 "test_must_fail: valgrind error: $*"
	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 && test $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() {
	$GIT_TEST_CMP "$@"
	}

	# test_cmp_bin - helper to compare binary files

	test_cmp_bin() {
	cmp "$@"
	}

	# Call any command "$@" but be more verbose about its
	# failure. This is handy for commands like "test" which do
	# not output anything when they fail.
	verbose () {
	"$@" && return 0
	echo >&2 "command failed: $(git rev-parse --sq-quote "$@")"
	return 1
	}

	# Check if the file expected to be empty is indeed empty, and barfs
	# otherwise.

	test_must_be_empty () {
	if test -s "$1"
	then
	echo "'$1' is not empty, it contains:"
	cat "$1"
	return 1
	fi
	}

	# Tests that its two parameters refer to the same revision
	test_cmp_rev () {
	git rev-parse --verify "$1" >expect.rev &&
	git rev-parse --verify "$2" >actual.rev &&
	test_cmp expect.rev actual.rev
	}

	# Print a sequence of numbers or letters in increasing order. This is
	# similar to GNU seq(1), but the latter might not be available
	# everywhere (and does not do letters). It may be used like:
	#
	# for i in $(test_seq 100)
	# do
	# for j in $(test_seq 10 20)
	# do
	# for k in $(test_seq a z)
	# do
	# echo $i-$j-$k
	# done
	# done
	# done

	test_seq () {
	case $# in
	1) set 1 "$@" ;;
	2) ;;
	*) error "bug in the test script: not 1 or 2 parameters to test_seq" ;;
	esac
	perl -le 'print for $ARGV[0]..$ARGV[1]' -- "$@"
	}

	# 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
	}

	# This function helps on symlink challenged file systems when it is not
	# important that the file system entry is a symbolic link.
	# Use test_ln_s_add instead of "ln -s x y && git add y" to add a
	# symbolic link entry y to the index.

	test_ln_s_add () {
	if test_have_prereq SYMLINKS
	then
	ln -s "$1" "$2" &&
	git update-index --add "$2"
	else
	printf '%s' "$1" >"$2" &&
	ln_s_obj=$(git hash-object -w "$2") &&
	git update-index --add --cacheinfo 120000 $ln_s_obj "$2"
	fi
	}

	# This function writes out its parameters, one per line
	test_write_lines () {
	printf "%s\n" "$@"
	}

	perl () {
	command "$PERL_PATH" "$@"
	}

	# Is the value one of the various ways to spell a boolean true/false?
	test_normalize_bool () {
	git -c magic.variable="$1" config --bool magic.variable 2>/dev/null
	}

	# Given a variable $1, normalize the value of it to one of "true",
	# "false", or "auto" and store the result to it.
	#
	# test_tristate GIT_TEST_HTTPD
	#
	# A variable set to an empty string is set to 'false'.
	# A variable set to 'false' or 'auto' keeps its value.
	# Anything else is set to 'true'.
	# An unset variable defaults to 'auto'.
	#
	# The last rule is to allow people to set the variable to an empty
	# string and export it to decline testing the particular feature
	# for versions both before and after this change. We used to treat
	# both unset and empty variable as a signal for "do not test" and
	# took any non-empty string as "please test".

	test_tristate () {
	if eval "test x\"\${$1+isset}\" = xisset"
	then
	# explicitly set
	eval "
	case \"\$$1\" in
	'') $1=false ;;
	auto) ;;
	*) $1=\$(test_normalize_bool \$$1 \|\| echo true) ;;
	esac
	"
	else
	eval "$1=auto"
	fi
	}

	# Exit the test suite, either by skipping all remaining tests or by
	# exiting with an error. If "$1" is "auto", we then we assume we were
	# opportunistically trying to set up some tests and we skip. If it is
	# "true", then we report a failure.
	#
	# The error/skip message should be given by $2.
	#
	test_skip_or_die () {
	case "$1" in
	auto)
	skip_all=$2
	test_done
	;;
	true)
	error "$2"
	;;
	*)
	error "BUG: test tristate is '$1' (real error: $2)"
	esac
	}

	# The following mingw_* functions obey POSIX shell syntax, but are actually
	# bash scripts, and are meant to be used only with bash on Windows.

	# A test_cmp function that treats LF and CRLF equal and avoids to fork
	# diff when possible.
	mingw_test_cmp () {
	# Read text into shell variables and compare them. If the results
	# are different, use regular diff to report the difference.
	local test_cmp_a= test_cmp_b=

	# When text came from stdin (one argument is '-') we must feed it
	# to diff.
	local stdin_for_diff=

	# Since it is difficult to detect the difference between an
	# empty input file and a failure to read the files, we go straight
	# to diff if one of the inputs is empty.
	if test -s "$1" && test -s "$2"
	then
	# regular case: both files non-empty
	mingw_read_file_strip_cr_ test_cmp_a <"$1"
	mingw_read_file_strip_cr_ test_cmp_b <"$2"
	elif test -s "$1" && test "$2" = -
	then
	# read 2nd file from stdin
	mingw_read_file_strip_cr_ test_cmp_a <"$1"
	mingw_read_file_strip_cr_ test_cmp_b
	stdin_for_diff='<<<"$test_cmp_b"'
	elif test "$1" = - && test -s "$2"
	then
	# read 1st file from stdin
	mingw_read_file_strip_cr_ test_cmp_a
	mingw_read_file_strip_cr_ test_cmp_b <"$2"
	stdin_for_diff='<<<"$test_cmp_a"'
	fi
	test -n "$test_cmp_a" &&
	test -n "$test_cmp_b" &&
	test "$test_cmp_a" = "$test_cmp_b" \|\|
	eval "diff -u \"\$@\" $stdin_for_diff"
	}

	# $1 is the name of the shell variable to fill in
	mingw_read_file_strip_cr_ () {
	# Read line-wise using LF as the line separator
	# and use IFS to strip CR.
	local line
	while :
	do
	if IFS=$'\r' read -r -d $'\n' line
	then
	# good
	line=$line$'\n'
	else
	# we get here at EOF, but also if the last line
	# was not terminated by LF; in the latter case,
	# some text was read
	if test -z "$line"
	then
	# EOF, really
	break
	fi
	fi
	eval "$1=\$$1\$line"
	done
	}