Andrew's git / gitweb.git / t/test-lib-functions.sh
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t / test-lib-functions.shon commit builtin/commit.c: extract ignore_non_trailer() helper function (073bd75)
   1#!/bin/sh
   2#
   3# Copyright (c) 2005 Junio C Hamano
   4#
   5# This program is free software: you can redistribute it and/or modify
   6# it under the terms of the GNU General Public License as published by
   7# the Free Software Foundation, either version 2 of the License, or
   8# (at your option) any later version.
   9#
  10# This program is distributed in the hope that it will be useful,
  11# but WITHOUT ANY WARRANTY; without even the implied warranty of
  12# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13# GNU General Public License for more details.
  14#
  15# You should have received a copy of the GNU General Public License
  16# along with this program.  If not, see http://www.gnu.org/licenses/ .
  17
  18# The semantics of the editor variables are that of invoking
  19# sh -c "$EDITOR \"$@\"" files ...
  20#
  21# If our trash directory contains shell metacharacters, they will be
  22# interpreted if we just set $EDITOR directly, so do a little dance with
  23# environment variables to work around this.
  24#
  25# In particular, quoting isn't enough, as the path may contain the same quote
  26# that we're using.
  27test_set_editor () {
  28        FAKE_EDITOR="$1"
  29        export FAKE_EDITOR
  30        EDITOR='"$FAKE_EDITOR"'
  31        export EDITOR
  32}
  33
  34test_decode_color () {
  35        awk '
  36                function name(n) {
  37                        if (n == 0) return "RESET";
  38                        if (n == 1) return "BOLD";
  39                        if (n == 30) return "BLACK";
  40                        if (n == 31) return "RED";
  41                        if (n == 32) return "GREEN";
  42                        if (n == 33) return "YELLOW";
  43                        if (n == 34) return "BLUE";
  44                        if (n == 35) return "MAGENTA";
  45                        if (n == 36) return "CYAN";
  46                        if (n == 37) return "WHITE";
  47                        if (n == 40) return "BLACK";
  48                        if (n == 41) return "BRED";
  49                        if (n == 42) return "BGREEN";
  50                        if (n == 43) return "BYELLOW";
  51                        if (n == 44) return "BBLUE";
  52                        if (n == 45) return "BMAGENTA";
  53                        if (n == 46) return "BCYAN";
  54                        if (n == 47) return "BWHITE";
  55                }
  56                {
  57                        while (match($0, /\033\[[0-9;]*m/) != 0) {
  58                                printf "%s<", substr($0, 1, RSTART-1);
  59                                codes = substr($0, RSTART+2, RLENGTH-3);
  60                                if (length(codes) == 0)
  61                                        printf "%s", name(0)
  62                                else {
  63                                        n = split(codes, ary, ";");
  64                                        sep = "";
  65                                        for (i = 1; i <= n; i++) {
  66                                                printf "%s%s", sep, name(ary[i]);
  67                                                sep = ";"
  68                                        }
  69                                }
  70                                printf ">";
  71                                $0 = substr($0, RSTART + RLENGTH, length($0) - RSTART - RLENGTH + 1);
  72                        }
  73                        print
  74                }
  75        '
  76}
  77
  78nul_to_q () {
  79        perl -pe 'y/\000/Q/'
  80}
  81
  82q_to_nul () {
  83        perl -pe 'y/Q/\000/'
  84}
  85
  86q_to_cr () {
  87        tr Q '\015'
  88}
  89
  90q_to_tab () {
  91        tr Q '\011'
  92}
  93
  94qz_to_tab_space () {
  95        tr QZ '\011\040'
  96}
  97
  98append_cr () {
  99        sed -e 's/$/Q/' | tr Q '\015'
 100}
 101
 102remove_cr () {
 103        tr '\015' Q | sed -e 's/Q$//'
 104}
 105
 106# In some bourne shell implementations, the "unset" builtin returns
 107# nonzero status when a variable to be unset was not set in the first
 108# place.
 109#
 110# Use sane_unset when that should not be considered an error.
 111
 112sane_unset () {
 113        unset "$@"
 114        return 0
 115}
 116
 117test_tick () {
 118        if test -z "${test_tick+set}"
 119        then
 120                test_tick=1112911993
 121        else
 122                test_tick=$(($test_tick + 60))
 123        fi
 124        GIT_COMMITTER_DATE="$test_tick -0700"
 125        GIT_AUTHOR_DATE="$test_tick -0700"
 126        export GIT_COMMITTER_DATE GIT_AUTHOR_DATE
 127}
 128
 129# Stop execution and start a shell. This is useful for debugging tests and
 130# only makes sense together with "-v".
 131#
 132# Be sure to remove all invocations of this command before submitting.
 133
 134test_pause () {
 135        if test "$verbose" = t; then
 136                "$SHELL_PATH" <&6 >&3 2>&4
 137        else
 138                error >&5 "test_pause requires --verbose"
 139        fi
 140}
 141
 142# Call test_commit with the arguments "<message> [<file> [<contents> [<tag>]]]"
 143#
 144# This will commit a file with the given contents and the given commit
 145# message, and tag the resulting commit with the given tag name.
 146#
 147# <file>, <contents>, and <tag> all default to <message>.
 148
 149test_commit () {
 150        notick= &&
 151        signoff= &&
 152        while test $# != 0
 153        do
 154                case "$1" in
 155                --notick)
 156                        notick=yes
 157                        ;;
 158                --signoff)
 159                        signoff="$1"
 160                        ;;
 161                *)
 162                        break
 163                        ;;
 164                esac
 165                shift
 166        done &&
 167        file=${2:-"$1.t"} &&
 168        echo "${3-$1}" > "$file" &&
 169        git add "$file" &&
 170        if test -z "$notick"
 171        then
 172                test_tick
 173        fi &&
 174        git commit $signoff -m "$1" &&
 175        git tag "${4:-$1}"
 176}
 177
 178# Call test_merge with the arguments "<message> <commit>", where <commit>
 179# can be a tag pointing to the commit-to-merge.
 180
 181test_merge () {
 182        test_tick &&
 183        git merge -m "$1" "$2" &&
 184        git tag "$1"
 185}
 186
 187# This function helps systems where core.filemode=false is set.
 188# Use it instead of plain 'chmod +x' to set or unset the executable bit
 189# of a file in the working directory and add it to the index.
 190
 191test_chmod () {
 192        chmod "$@" &&
 193        git update-index --add "--chmod=$@"
 194}
 195
 196# Unset a configuration variable, but don't fail if it doesn't exist.
 197test_unconfig () {
 198        git config --unset-all "$@"
 199        config_status=$?
 200        case "$config_status" in
 201        5) # ok, nothing to unset
 202                config_status=0
 203                ;;
 204        esac
 205        return $config_status
 206}
 207
 208# Set git config, automatically unsetting it after the test is over.
 209test_config () {
 210        test_when_finished "test_unconfig '$1'" &&
 211        git config "$@"
 212}
 213
 214test_config_global () {
 215        test_when_finished "test_unconfig --global '$1'" &&
 216        git config --global "$@"
 217}
 218
 219write_script () {
 220        {
 221                echo "#!${2-"$SHELL_PATH"}" &&
 222                cat
 223        } >"$1" &&
 224        chmod +x "$1"
 225}
 226
 227# Use test_set_prereq to tell that a particular prerequisite is available.
 228# The prerequisite can later be checked for in two ways:
 229#
 230# - Explicitly using test_have_prereq.
 231#
 232# - Implicitly by specifying the prerequisite tag in the calls to
 233#   test_expect_{success,failure,code}.
 234#
 235# The single parameter is the prerequisite tag (a simple word, in all
 236# capital letters by convention).
 237
 238test_set_prereq () {
 239        satisfied_prereq="$satisfied_prereq$1 "
 240}
 241satisfied_prereq=" "
 242lazily_testable_prereq= lazily_tested_prereq=
 243
 244# Usage: test_lazy_prereq PREREQ 'script'
 245test_lazy_prereq () {
 246        lazily_testable_prereq="$lazily_testable_prereq$1 "
 247        eval test_prereq_lazily_$1=\$2
 248}
 249
 250test_run_lazy_prereq_ () {
 251        script='
 252mkdir -p "$TRASH_DIRECTORY/prereq-test-dir" &&
 253(
 254        cd "$TRASH_DIRECTORY/prereq-test-dir" &&'"$2"'
 255)'
 256        say >&3 "checking prerequisite: $1"
 257        say >&3 "$script"
 258        test_eval_ "$script"
 259        eval_ret=$?
 260        rm -rf "$TRASH_DIRECTORY/prereq-test-dir"
 261        if test "$eval_ret" = 0; then
 262                say >&3 "prerequisite $1 ok"
 263        else
 264                say >&3 "prerequisite $1 not satisfied"
 265        fi
 266        return $eval_ret
 267}
 268
 269test_have_prereq () {
 270        # prerequisites can be concatenated with ','
 271        save_IFS=$IFS
 272        IFS=,
 273        set -- $*
 274        IFS=$save_IFS
 275
 276        total_prereq=0
 277        ok_prereq=0
 278        missing_prereq=
 279
 280        for prerequisite
 281        do
 282                case "$prerequisite" in
 283                !*)
 284                        negative_prereq=t
 285                        prerequisite=${prerequisite#!}
 286                        ;;
 287                *)
 288                        negative_prereq=
 289                esac
 290
 291                case " $lazily_tested_prereq " in
 292                *" $prerequisite "*)
 293                        ;;
 294                *)
 295                        case " $lazily_testable_prereq " in
 296                        *" $prerequisite "*)
 297                                eval "script=\$test_prereq_lazily_$prerequisite" &&
 298                                if test_run_lazy_prereq_ "$prerequisite" "$script"
 299                                then
 300                                        test_set_prereq $prerequisite
 301                                fi
 302                                lazily_tested_prereq="$lazily_tested_prereq$prerequisite "
 303                        esac
 304                        ;;
 305                esac
 306
 307                total_prereq=$(($total_prereq + 1))
 308                case "$satisfied_prereq" in
 309                *" $prerequisite "*)
 310                        satisfied_this_prereq=t
 311                        ;;
 312                *)
 313                        satisfied_this_prereq=
 314                esac
 315
 316                case "$satisfied_this_prereq,$negative_prereq" in
 317                t,|,t)
 318                        ok_prereq=$(($ok_prereq + 1))
 319                        ;;
 320                *)
 321                        # Keep a list of missing prerequisites; restore
 322                        # the negative marker if necessary.
 323                        prerequisite=${negative_prereq:+!}$prerequisite
 324                        if test -z "$missing_prereq"
 325                        then
 326                                missing_prereq=$prerequisite
 327                        else
 328                                missing_prereq="$prerequisite,$missing_prereq"
 329                        fi
 330                esac
 331        done
 332
 333        test $total_prereq = $ok_prereq
 334}
 335
 336test_declared_prereq () {
 337        case ",$test_prereq," in
 338        *,$1,*)
 339                return 0
 340                ;;
 341        esac
 342        return 1
 343}
 344
 345test_expect_failure () {
 346        test_start_
 347        test "$#" = 3 && { test_prereq=$1; shift; } || test_prereq=
 348        test "$#" = 2 ||
 349        error "bug in the test script: not 2 or 3 parameters to test-expect-failure"
 350        export test_prereq
 351        if ! test_skip "$@"
 352        then
 353                say >&3 "checking known breakage: $2"
 354                if test_run_ "$2" expecting_failure
 355                then
 356                        test_known_broken_ok_ "$1"
 357                else
 358                        test_known_broken_failure_ "$1"
 359                fi
 360        fi
 361        test_finish_
 362}
 363
 364test_expect_success () {
 365        test_start_
 366        test "$#" = 3 && { test_prereq=$1; shift; } || test_prereq=
 367        test "$#" = 2 ||
 368        error "bug in the test script: not 2 or 3 parameters to test-expect-success"
 369        export test_prereq
 370        if ! test_skip "$@"
 371        then
 372                say >&3 "expecting success: $2"
 373                if test_run_ "$2"
 374                then
 375                        test_ok_ "$1"
 376                else
 377                        test_failure_ "$@"
 378                fi
 379        fi
 380        test_finish_
 381}
 382
 383# test_external runs external test scripts that provide continuous
 384# test output about their progress, and succeeds/fails on
 385# zero/non-zero exit code.  It outputs the test output on stdout even
 386# in non-verbose mode, and announces the external script with "# run
 387# <n>: ..." before running it.  When providing relative paths, keep in
 388# mind that all scripts run in "trash directory".
 389# Usage: test_external description command arguments...
 390# Example: test_external 'Perl API' perl ../path/to/test.pl
 391test_external () {
 392        test "$#" = 4 && { test_prereq=$1; shift; } || test_prereq=
 393        test "$#" = 3 ||
 394        error >&5 "bug in the test script: not 3 or 4 parameters to test_external"
 395        descr="$1"
 396        shift
 397        export test_prereq
 398        if ! test_skip "$descr" "$@"
 399        then
 400                # Announce the script to reduce confusion about the
 401                # test output that follows.
 402                say_color "" "# run $test_count: $descr ($*)"
 403                # Export TEST_DIRECTORY, TRASH_DIRECTORY and GIT_TEST_LONG
 404                # to be able to use them in script
 405                export TEST_DIRECTORY TRASH_DIRECTORY GIT_TEST_LONG
 406                # Run command; redirect its stderr to &4 as in
 407                # test_run_, but keep its stdout on our stdout even in
 408                # non-verbose mode.
 409                "$@" 2>&4
 410                if [ "$?" = 0 ]
 411                then
 412                        if test $test_external_has_tap -eq 0; then
 413                                test_ok_ "$descr"
 414                        else
 415                                say_color "" "# test_external test $descr was ok"
 416                                test_success=$(($test_success + 1))
 417                        fi
 418                else
 419                        if test $test_external_has_tap -eq 0; then
 420                                test_failure_ "$descr" "$@"
 421                        else
 422                                say_color error "# test_external test $descr failed: $@"
 423                                test_failure=$(($test_failure + 1))
 424                        fi
 425                fi
 426        fi
 427}
 428
 429# Like test_external, but in addition tests that the command generated
 430# no output on stderr.
 431test_external_without_stderr () {
 432        # The temporary file has no (and must have no) security
 433        # implications.
 434        tmp=${TMPDIR:-/tmp}
 435        stderr="$tmp/git-external-stderr.$$.tmp"
 436        test_external "$@" 4> "$stderr"
 437        [ -f "$stderr" ] || error "Internal error: $stderr disappeared."
 438        descr="no stderr: $1"
 439        shift
 440        say >&3 "# expecting no stderr from previous command"
 441        if [ ! -s "$stderr" ]; then
 442                rm "$stderr"
 443
 444                if test $test_external_has_tap -eq 0; then
 445                        test_ok_ "$descr"
 446                else
 447                        say_color "" "# test_external_without_stderr test $descr was ok"
 448                        test_success=$(($test_success + 1))
 449                fi
 450        else
 451                if [ "$verbose" = t ]; then
 452                        output=`echo; echo "# Stderr is:"; cat "$stderr"`
 453                else
 454                        output=
 455                fi
 456                # rm first in case test_failure exits.
 457                rm "$stderr"
 458                if test $test_external_has_tap -eq 0; then
 459                        test_failure_ "$descr" "$@" "$output"
 460                else
 461                        say_color error "# test_external_without_stderr test $descr failed: $@: $output"
 462                        test_failure=$(($test_failure + 1))
 463                fi
 464        fi
 465}
 466
 467# debugging-friendly alternatives to "test [-f|-d|-e]"
 468# The commands test the existence or non-existence of $1. $2 can be
 469# given to provide a more precise diagnosis.
 470test_path_is_file () {
 471        if ! [ -f "$1" ]
 472        then
 473                echo "File $1 doesn't exist. $*"
 474                false
 475        fi
 476}
 477
 478test_path_is_dir () {
 479        if ! [ -d "$1" ]
 480        then
 481                echo "Directory $1 doesn't exist. $*"
 482                false
 483        fi
 484}
 485
 486test_path_is_missing () {
 487        if [ -e "$1" ]
 488        then
 489                echo "Path exists:"
 490                ls -ld "$1"
 491                if [ $# -ge 1 ]; then
 492                        echo "$*"
 493                fi
 494                false
 495        fi
 496}
 497
 498# test_line_count checks that a file has the number of lines it
 499# ought to. For example:
 500#
 501#       test_expect_success 'produce exactly one line of output' '
 502#               do something >output &&
 503#               test_line_count = 1 output
 504#       '
 505#
 506# is like "test $(wc -l <output) = 1" except that it passes the
 507# output through when the number of lines is wrong.
 508
 509test_line_count () {
 510        if test $# != 3
 511        then
 512                error "bug in the test script: not 3 parameters to test_line_count"
 513        elif ! test $(wc -l <"$3") "$1" "$2"
 514        then
 515                echo "test_line_count: line count for $3 !$1 $2"
 516                cat "$3"
 517                return 1
 518        fi
 519}
 520
 521# This is not among top-level (test_expect_success | test_expect_failure)
 522# but is a prefix that can be used in the test script, like:
 523#
 524#       test_expect_success 'complain and die' '
 525#           do something &&
 526#           do something else &&
 527#           test_must_fail git checkout ../outerspace
 528#       '
 529#
 530# Writing this as "! git checkout ../outerspace" is wrong, because
 531# the failure could be due to a segv.  We want a controlled failure.
 532
 533test_must_fail () {
 534        "$@"
 535        exit_code=$?
 536        if test $exit_code = 0; then
 537                echo >&2 "test_must_fail: command succeeded: $*"
 538                return 1
 539        elif test $exit_code -gt 129 -a $exit_code -le 192; then
 540                echo >&2 "test_must_fail: died by signal: $*"
 541                return 1
 542        elif test $exit_code = 127; then
 543                echo >&2 "test_must_fail: command not found: $*"
 544                return 1
 545        elif test $exit_code = 126; then
 546                echo >&2 "test_must_fail: valgrind error: $*"
 547                return 1
 548        fi
 549        return 0
 550}
 551
 552# Similar to test_must_fail, but tolerates success, too.  This is
 553# meant to be used in contexts like:
 554#
 555#       test_expect_success 'some command works without configuration' '
 556#               test_might_fail git config --unset all.configuration &&
 557#               do something
 558#       '
 559#
 560# Writing "git config --unset all.configuration || :" would be wrong,
 561# because we want to notice if it fails due to segv.
 562
 563test_might_fail () {
 564        "$@"
 565        exit_code=$?
 566        if test $exit_code -gt 129 -a $exit_code -le 192; then
 567                echo >&2 "test_might_fail: died by signal: $*"
 568                return 1
 569        elif test $exit_code = 127; then
 570                echo >&2 "test_might_fail: command not found: $*"
 571                return 1
 572        fi
 573        return 0
 574}
 575
 576# Similar to test_must_fail and test_might_fail, but check that a
 577# given command exited with a given exit code. Meant to be used as:
 578#
 579#       test_expect_success 'Merge with d/f conflicts' '
 580#               test_expect_code 1 git merge "merge msg" B master
 581#       '
 582
 583test_expect_code () {
 584        want_code=$1
 585        shift
 586        "$@"
 587        exit_code=$?
 588        if test $exit_code = $want_code
 589        then
 590                return 0
 591        fi
 592
 593        echo >&2 "test_expect_code: command exited with $exit_code, we wanted $want_code $*"
 594        return 1
 595}
 596
 597# test_cmp is a helper function to compare actual and expected output.
 598# You can use it like:
 599#
 600#       test_expect_success 'foo works' '
 601#               echo expected >expected &&
 602#               foo >actual &&
 603#               test_cmp expected actual
 604#       '
 605#
 606# This could be written as either "cmp" or "diff -u", but:
 607# - cmp's output is not nearly as easy to read as diff -u
 608# - not all diff versions understand "-u"
 609
 610test_cmp() {
 611        $GIT_TEST_CMP "$@"
 612}
 613
 614# Check if the file expected to be empty is indeed empty, and barfs
 615# otherwise.
 616
 617test_must_be_empty () {
 618        if test -s "$1"
 619        then
 620                echo "'$1' is not empty, it contains:"
 621                cat "$1"
 622                return 1
 623        fi
 624}
 625
 626# Tests that its two parameters refer to the same revision
 627test_cmp_rev () {
 628        git rev-parse --verify "$1" >expect.rev &&
 629        git rev-parse --verify "$2" >actual.rev &&
 630        test_cmp expect.rev actual.rev
 631}
 632
 633# Print a sequence of numbers or letters in increasing order.  This is
 634# similar to GNU seq(1), but the latter might not be available
 635# everywhere (and does not do letters).  It may be used like:
 636#
 637#       for i in `test_seq 100`; do
 638#               for j in `test_seq 10 20`; do
 639#                       for k in `test_seq a z`; do
 640#                               echo $i-$j-$k
 641#                       done
 642#               done
 643#       done
 644
 645test_seq () {
 646        case $# in
 647        1)      set 1 "$@" ;;
 648        2)      ;;
 649        *)      error "bug in the test script: not 1 or 2 parameters to test_seq" ;;
 650        esac
 651        perl -le 'print for $ARGV[0]..$ARGV[1]' -- "$@"
 652}
 653
 654# This function can be used to schedule some commands to be run
 655# unconditionally at the end of the test to restore sanity:
 656#
 657#       test_expect_success 'test core.capslock' '
 658#               git config core.capslock true &&
 659#               test_when_finished "git config --unset core.capslock" &&
 660#               hello world
 661#       '
 662#
 663# That would be roughly equivalent to
 664#
 665#       test_expect_success 'test core.capslock' '
 666#               git config core.capslock true &&
 667#               hello world
 668#               git config --unset core.capslock
 669#       '
 670#
 671# except that the greeting and config --unset must both succeed for
 672# the test to pass.
 673#
 674# Note that under --immediate mode, no clean-up is done to help diagnose
 675# what went wrong.
 676
 677test_when_finished () {
 678        test_cleanup="{ $*
 679                } && (exit \"\$eval_ret\"); eval_ret=\$?; $test_cleanup"
 680}
 681
 682# Most tests can use the created repository, but some may need to create more.
 683# Usage: test_create_repo <directory>
 684test_create_repo () {
 685        test "$#" = 1 ||
 686        error "bug in the test script: not 1 parameter to test-create-repo"
 687        repo="$1"
 688        mkdir -p "$repo"
 689        (
 690                cd "$repo" || error "Cannot setup test environment"
 691                "$GIT_EXEC_PATH/git-init" "--template=$GIT_BUILD_DIR/templates/blt/" >&3 2>&4 ||
 692                error "cannot run git init -- have you built things yet?"
 693                mv .git/hooks .git/hooks-disabled
 694        ) || exit
 695}
 696
 697# This function helps on symlink challenged file systems when it is not
 698# important that the file system entry is a symbolic link.
 699# Use test_ln_s_add instead of "ln -s x y && git add y" to add a
 700# symbolic link entry y to the index.
 701
 702test_ln_s_add () {
 703        if test_have_prereq SYMLINKS
 704        then
 705                ln -s "$1" "$2" &&
 706                git update-index --add "$2"
 707        else
 708                printf '%s' "$1" >"$2" &&
 709                ln_s_obj=$(git hash-object -w "$2") &&
 710                git update-index --add --cacheinfo 120000 $ln_s_obj "$2"
 711        fi
 712}
 713
 714perl () {
 715        command "$PERL_PATH" "$@"
 716}
 717
 718# The following mingw_* functions obey POSIX shell syntax, but are actually
 719# bash scripts, and are meant to be used only with bash on Windows.
 720
 721# A test_cmp function that treats LF and CRLF equal and avoids to fork
 722# diff when possible.
 723mingw_test_cmp () {
 724        # Read text into shell variables and compare them. If the results
 725        # are different, use regular diff to report the difference.
 726        local test_cmp_a= test_cmp_b=
 727
 728        # When text came from stdin (one argument is '-') we must feed it
 729        # to diff.
 730        local stdin_for_diff=
 731
 732        # Since it is difficult to detect the difference between an
 733        # empty input file and a failure to read the files, we go straight
 734        # to diff if one of the inputs is empty.
 735        if test -s "$1" && test -s "$2"
 736        then
 737                # regular case: both files non-empty
 738                mingw_read_file_strip_cr_ test_cmp_a <"$1"
 739                mingw_read_file_strip_cr_ test_cmp_b <"$2"
 740        elif test -s "$1" && test "$2" = -
 741        then
 742                # read 2nd file from stdin
 743                mingw_read_file_strip_cr_ test_cmp_a <"$1"
 744                mingw_read_file_strip_cr_ test_cmp_b
 745                stdin_for_diff='<<<"$test_cmp_b"'
 746        elif test "$1" = - && test -s "$2"
 747        then
 748                # read 1st file from stdin
 749                mingw_read_file_strip_cr_ test_cmp_a
 750                mingw_read_file_strip_cr_ test_cmp_b <"$2"
 751                stdin_for_diff='<<<"$test_cmp_a"'
 752        fi
 753        test -n "$test_cmp_a" &&
 754        test -n "$test_cmp_b" &&
 755        test "$test_cmp_a" = "$test_cmp_b" ||
 756        eval "diff -u \"\$@\" $stdin_for_diff"
 757}
 758
 759# $1 is the name of the shell variable to fill in
 760mingw_read_file_strip_cr_ () {
 761        # Read line-wise using LF as the line separator
 762        # and use IFS to strip CR.
 763        local line
 764        while :
 765        do
 766                if IFS=$'\r' read -r -d $'\n' line
 767                then
 768                        # good
 769                        line=$line$'\n'
 770                else
 771                        # we get here at EOF, but also if the last line
 772                        # was not terminated by LF; in the latter case,
 773                        # some text was read
 774                        if test -z "$line"
 775                        then
 776                                # EOF, really
 777                                break
 778                        fi
 779                fi
 780                eval "$1=\$$1\$line"
 781        done
 782}