git-bisect.shon commit Makes some cleanup/review in gittutorial (21d777f)
   1#!/bin/sh
   2
   3USAGE='[help|start|bad|good|skip|next|reset|visualize|replay|log|run]'
   4LONG_USAGE='git bisect help
   5        print this long help message.
   6git bisect start [<bad> [<good>...]] [--] [<pathspec>...]
   7        reset bisect state and start bisection.
   8git bisect bad [<rev>]
   9        mark <rev> a known-bad revision.
  10git bisect good [<rev>...]
  11        mark <rev>... known-good revisions.
  12git bisect skip [(<rev>|<range>)...]
  13        mark <rev>... untestable revisions.
  14git bisect next
  15        find next bisection to test and check it out.
  16git bisect reset [<branch>]
  17        finish bisection search and go back to branch.
  18git bisect visualize
  19        show bisect status in gitk.
  20git bisect replay <logfile>
  21        replay bisection log.
  22git bisect log
  23        show bisect log.
  24git bisect run <cmd>...
  25        use <cmd>... to automatically bisect.
  26
  27Please use "git help bisect" to get the full man page.'
  28
  29OPTIONS_SPEC=
  30. git-sh-setup
  31require_work_tree
  32
  33_x40='[0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]'
  34_x40="$_x40$_x40$_x40$_x40$_x40$_x40$_x40$_x40"
  35
  36sq() {
  37        @@PERL@@ -e '
  38                for (@ARGV) {
  39                        s/'\''/'\'\\\\\'\''/g;
  40                        print " '\''$_'\''";
  41                }
  42                print "\n";
  43        ' "$@"
  44}
  45
  46bisect_autostart() {
  47        test -s "$GIT_DIR/BISECT_START" || {
  48                echo >&2 'You need to start by "git bisect start"'
  49                if test -t 0
  50                then
  51                        echo >&2 -n 'Do you want me to do it for you [Y/n]? '
  52                        read yesno
  53                        case "$yesno" in
  54                        [Nn]*)
  55                                exit ;;
  56                        esac
  57                        bisect_start
  58                else
  59                        exit 1
  60                fi
  61        }
  62}
  63
  64bisect_start() {
  65        #
  66        # Verify HEAD.
  67        #
  68        head=$(GIT_DIR="$GIT_DIR" git symbolic-ref -q HEAD) ||
  69        head=$(GIT_DIR="$GIT_DIR" git rev-parse --verify HEAD) ||
  70        die "Bad HEAD - I need a HEAD"
  71
  72        #
  73        # Check if we are bisecting.
  74        #
  75        start_head=''
  76        if test -s "$GIT_DIR/BISECT_START"
  77        then
  78                # Reset to the rev from where we started.
  79                start_head=$(cat "$GIT_DIR/BISECT_START")
  80                git checkout "$start_head" -- || exit
  81        else
  82                # Get rev from where we start.
  83                case "$head" in
  84                refs/heads/*|$_x40)
  85                        # This error message should only be triggered by
  86                        # cogito usage, and cogito users should understand
  87                        # it relates to cg-seek.
  88                        [ -s "$GIT_DIR/head-name" ] &&
  89                                die "won't bisect on seeked tree"
  90                        start_head="${head#refs/heads/}"
  91                        ;;
  92                *)
  93                        die "Bad HEAD - strange symbolic ref"
  94                        ;;
  95                esac
  96        fi
  97
  98        #
  99        # Get rid of any old bisect state.
 100        #
 101        bisect_clean_state || exit
 102
 103        #
 104        # Check for one bad and then some good revisions.
 105        #
 106        has_double_dash=0
 107        for arg; do
 108            case "$arg" in --) has_double_dash=1; break ;; esac
 109        done
 110        orig_args=$(sq "$@")
 111        bad_seen=0
 112        eval=''
 113        while [ $# -gt 0 ]; do
 114            arg="$1"
 115            case "$arg" in
 116            --)
 117                shift
 118                break
 119                ;;
 120            *)
 121                rev=$(git rev-parse -q --verify "$arg^{commit}") || {
 122                    test $has_double_dash -eq 1 &&
 123                        die "'$arg' does not appear to be a valid revision"
 124                    break
 125                }
 126                case $bad_seen in
 127                0) state='bad' ; bad_seen=1 ;;
 128                *) state='good' ;;
 129                esac
 130                eval="$eval bisect_write '$state' '$rev' 'nolog'; "
 131                shift
 132                ;;
 133            esac
 134        done
 135
 136        #
 137        # Change state.
 138        # In case of mistaken revs or checkout error, or signals received,
 139        # "bisect_auto_next" below may exit or misbehave.
 140        # We have to trap this to be able to clean up using
 141        # "bisect_clean_state".
 142        #
 143        trap 'bisect_clean_state' 0
 144        trap 'exit 255' 1 2 3 15
 145
 146        #
 147        # Write new start state.
 148        #
 149        echo "$start_head" >"$GIT_DIR/BISECT_START" &&
 150        sq "$@" >"$GIT_DIR/BISECT_NAMES" &&
 151        eval "$eval" &&
 152        echo "git bisect start$orig_args" >>"$GIT_DIR/BISECT_LOG" || exit
 153        #
 154        # Check if we can proceed to the next bisect state.
 155        #
 156        bisect_auto_next
 157
 158        trap '-' 0
 159}
 160
 161bisect_write() {
 162        state="$1"
 163        rev="$2"
 164        nolog="$3"
 165        case "$state" in
 166                bad)            tag="$state" ;;
 167                good|skip)      tag="$state"-"$rev" ;;
 168                *)              die "Bad bisect_write argument: $state" ;;
 169        esac
 170        git update-ref "refs/bisect/$tag" "$rev" || exit
 171        echo "# $state: $(git show-branch $rev)" >>"$GIT_DIR/BISECT_LOG"
 172        test -n "$nolog" || echo "git bisect $state $rev" >>"$GIT_DIR/BISECT_LOG"
 173}
 174
 175is_expected_rev() {
 176        test -f "$GIT_DIR/BISECT_EXPECTED_REV" &&
 177        test "$1" = $(cat "$GIT_DIR/BISECT_EXPECTED_REV")
 178}
 179
 180mark_expected_rev() {
 181        echo "$1" > "$GIT_DIR/BISECT_EXPECTED_REV"
 182}
 183
 184check_expected_revs() {
 185        for _rev in "$@"; do
 186                if ! is_expected_rev "$_rev"; then
 187                        rm -f "$GIT_DIR/BISECT_ANCESTORS_OK"
 188                        rm -f "$GIT_DIR/BISECT_EXPECTED_REV"
 189                        return
 190                fi
 191        done
 192}
 193
 194bisect_skip() {
 195        all=''
 196        for arg in "$@"
 197        do
 198            case "$arg" in
 199            *..*)
 200                revs=$(git rev-list "$arg") || die "Bad rev input: $arg" ;;
 201            *)
 202                revs=$(sq "$arg") ;;
 203            esac
 204            all="$all $revs"
 205        done
 206        eval bisect_state 'skip' $all
 207}
 208
 209bisect_state() {
 210        bisect_autostart
 211        state=$1
 212        case "$#,$state" in
 213        0,*)
 214                die "Please call 'bisect_state' with at least one argument." ;;
 215        1,bad|1,good|1,skip)
 216                rev=$(git rev-parse --verify HEAD) ||
 217                        die "Bad rev input: HEAD"
 218                bisect_write "$state" "$rev"
 219                check_expected_revs "$rev" ;;
 220        2,bad|*,good|*,skip)
 221                shift
 222                eval=''
 223                for rev in "$@"
 224                do
 225                        sha=$(git rev-parse --verify "$rev^{commit}") ||
 226                                die "Bad rev input: $rev"
 227                        eval="$eval bisect_write '$state' '$sha'; "
 228                done
 229                eval "$eval"
 230                check_expected_revs "$@" ;;
 231        *,bad)
 232                die "'git bisect bad' can take only one argument." ;;
 233        *)
 234                usage ;;
 235        esac
 236        bisect_auto_next
 237}
 238
 239bisect_next_check() {
 240        missing_good= missing_bad=
 241        git show-ref -q --verify refs/bisect/bad || missing_bad=t
 242        test -n "$(git for-each-ref "refs/bisect/good-*")" || missing_good=t
 243
 244        case "$missing_good,$missing_bad,$1" in
 245        ,,*)
 246                : have both good and bad - ok
 247                ;;
 248        *,)
 249                # do not have both but not asked to fail - just report.
 250                false
 251                ;;
 252        t,,good)
 253                # have bad but not good.  we could bisect although
 254                # this is less optimum.
 255                echo >&2 'Warning: bisecting only with a bad commit.'
 256                if test -t 0
 257                then
 258                        printf >&2 'Are you sure [Y/n]? '
 259                        read yesno
 260                        case "$yesno" in [Nn]*) exit 1 ;; esac
 261                fi
 262                : bisect without good...
 263                ;;
 264        *)
 265                THEN=''
 266                test -s "$GIT_DIR/BISECT_START" || {
 267                        echo >&2 'You need to start by "git bisect start".'
 268                        THEN='then '
 269                }
 270                echo >&2 'You '$THEN'need to give me at least one good' \
 271                        'and one bad revisions.'
 272                echo >&2 '(You can use "git bisect bad" and' \
 273                        '"git bisect good" for that.)'
 274                exit 1 ;;
 275        esac
 276}
 277
 278bisect_auto_next() {
 279        bisect_next_check && bisect_next || :
 280}
 281
 282exit_if_skipped_commits () {
 283        _tried=$1
 284        _bad=$2
 285        if test -n "$_tried" ; then
 286                echo "There are only 'skip'ped commit left to test."
 287                echo "The first bad commit could be any of:"
 288                echo "$_tried" | tr '[|]' '[\012]'
 289                test -n "$_bad" && echo "$_bad"
 290                echo "We cannot bisect more!"
 291                exit 2
 292        fi
 293}
 294
 295bisect_checkout() {
 296        _rev="$1"
 297        _msg="$2"
 298        echo "Bisecting: $_msg"
 299        mark_expected_rev "$_rev"
 300        git checkout -q "$_rev" -- || exit
 301        git show-branch "$_rev"
 302}
 303
 304is_among() {
 305        _rev="$1"
 306        _list="$2"
 307        case "$_list" in *$_rev*) return 0 ;; esac
 308        return 1
 309}
 310
 311handle_bad_merge_base() {
 312        _badmb="$1"
 313        _good="$2"
 314        if is_expected_rev "$_badmb"; then
 315                cat >&2 <<EOF
 316The merge base $_badmb is bad.
 317This means the bug has been fixed between $_badmb and [$_good].
 318EOF
 319                exit 3
 320        else
 321                cat >&2 <<EOF
 322Some good revs are not ancestor of the bad rev.
 323git bisect cannot work properly in this case.
 324Maybe you mistake good and bad revs?
 325EOF
 326                exit 1
 327        fi
 328}
 329
 330handle_skipped_merge_base() {
 331        _mb="$1"
 332        _bad="$2"
 333        _good="$3"
 334        cat >&2 <<EOF
 335Warning: the merge base between $_bad and [$_good] must be skipped.
 336So we cannot be sure the first bad commit is between $_mb and $_bad.
 337We continue anyway.
 338EOF
 339}
 340
 341#
 342# "check_merge_bases" checks that merge bases are not "bad".
 343#
 344# - If one is "good", that's good, we have nothing to do.
 345# - If one is "bad", it means the user assumed something wrong
 346# and we must exit.
 347# - If one is "skipped", we can't know but we should warn.
 348# - If we don't know, we should check it out and ask the user to test.
 349#
 350# In the last case we will return 1, and otherwise 0.
 351#
 352check_merge_bases() {
 353        _bad="$1"
 354        _good="$2"
 355        _skip="$3"
 356        for _mb in $(git merge-base --all $_bad $_good)
 357        do
 358                if is_among "$_mb" "$_good"; then
 359                        continue
 360                elif test "$_mb" = "$_bad"; then
 361                        handle_bad_merge_base "$_bad" "$_good"
 362                elif is_among "$_mb" "$_skip"; then
 363                        handle_skipped_merge_base "$_mb" "$_bad" "$_good"
 364                else
 365                        bisect_checkout "$_mb" "a merge base must be tested"
 366                        return 1
 367                fi
 368        done
 369        return 0
 370}
 371
 372#
 373# "check_good_are_ancestors_of_bad" checks that all "good" revs are
 374# ancestor of the "bad" rev.
 375#
 376# If that's not the case, we need to check the merge bases.
 377# If a merge base must be tested by the user we return 1 and
 378# otherwise 0.
 379#
 380check_good_are_ancestors_of_bad() {
 381        test -f "$GIT_DIR/BISECT_ANCESTORS_OK" &&
 382                return
 383
 384        _bad="$1"
 385        _good=$(echo $2 | sed -e 's/\^//g')
 386        _skip="$3"
 387
 388        # Bisecting with no good rev is ok
 389        test -z "$_good" && return
 390
 391        _side=$(git rev-list $_good ^$_bad)
 392        if test -n "$_side"; then
 393                # Return if a checkout was done
 394                check_merge_bases "$_bad" "$_good" "$_skip" || return
 395        fi
 396
 397        : > "$GIT_DIR/BISECT_ANCESTORS_OK"
 398
 399        return 0
 400}
 401
 402bisect_next() {
 403        case "$#" in 0) ;; *) usage ;; esac
 404        bisect_autostart
 405        bisect_next_check good
 406
 407        # Get bad, good and skipped revs
 408        bad=$(git rev-parse --verify refs/bisect/bad) &&
 409        good=$(git for-each-ref --format='^%(objectname)' \
 410                "refs/bisect/good-*" | tr '\012' ' ') &&
 411        skip=$(git for-each-ref --format='%(objectname)' \
 412                "refs/bisect/skip-*" | tr '\012' ' ') || exit
 413
 414        # Maybe some merge bases must be tested first
 415        check_good_are_ancestors_of_bad "$bad" "$good" "$skip"
 416        # Return now if a checkout has already been done
 417        test "$?" -eq "1" && return
 418
 419        # Get bisection information
 420        eval=$(eval "git bisect--helper --next-vars") &&
 421        eval "$eval" || exit
 422
 423        if [ -z "$bisect_rev" ]; then
 424                # We should exit here only if the "bad"
 425                # commit is also a "skip" commit (see above).
 426                exit_if_skipped_commits "$bisect_tried"
 427                echo "$bad was both good and bad"
 428                exit 1
 429        fi
 430        if [ "$bisect_rev" = "$bad" ]; then
 431                exit_if_skipped_commits "$bisect_tried" "$bad"
 432                echo "$bisect_rev is first bad commit"
 433                git diff-tree --pretty $bisect_rev
 434                exit 0
 435        fi
 436
 437        bisect_checkout "$bisect_rev" "$bisect_nr revisions left to test after this (roughly $bisect_steps steps)"
 438}
 439
 440bisect_visualize() {
 441        bisect_next_check fail
 442
 443        if test $# = 0
 444        then
 445                case "${DISPLAY+set}${SESSIONNAME+set}${MSYSTEM+set}${SECURITYSESSIONID+set}" in
 446                '')     set git log ;;
 447                set*)   set gitk ;;
 448                esac
 449        else
 450                case "$1" in
 451                git*|tig) ;;
 452                -*)     set git log "$@" ;;
 453                *)      set git "$@" ;;
 454                esac
 455        fi
 456
 457        not=$(git for-each-ref --format='%(refname)' "refs/bisect/good-*")
 458        eval '"$@"' refs/bisect/bad --not $not -- $(cat "$GIT_DIR/BISECT_NAMES")
 459}
 460
 461bisect_reset() {
 462        test -s "$GIT_DIR/BISECT_START" || {
 463                echo "We are not bisecting."
 464                return
 465        }
 466        case "$#" in
 467        0) branch=$(cat "$GIT_DIR/BISECT_START") ;;
 468        1) git show-ref --verify --quiet -- "refs/heads/$1" ||
 469               die "$1 does not seem to be a valid branch"
 470           branch="$1" ;;
 471        *)
 472            usage ;;
 473        esac
 474        git checkout "$branch" -- && bisect_clean_state
 475}
 476
 477bisect_clean_state() {
 478        # There may be some refs packed during bisection.
 479        git for-each-ref --format='%(refname) %(objectname)' refs/bisect/\* |
 480        while read ref hash
 481        do
 482                git update-ref -d $ref $hash || exit
 483        done
 484        rm -f "$GIT_DIR/BISECT_EXPECTED_REV" &&
 485        rm -f "$GIT_DIR/BISECT_ANCESTORS_OK" &&
 486        rm -f "$GIT_DIR/BISECT_LOG" &&
 487        rm -f "$GIT_DIR/BISECT_NAMES" &&
 488        rm -f "$GIT_DIR/BISECT_RUN" &&
 489        # Cleanup head-name if it got left by an old version of git-bisect
 490        rm -f "$GIT_DIR/head-name" &&
 491
 492        rm -f "$GIT_DIR/BISECT_START"
 493}
 494
 495bisect_replay () {
 496        test -r "$1" || die "cannot read $1 for replaying"
 497        bisect_reset
 498        while read git bisect command rev
 499        do
 500                test "$git $bisect" = "git bisect" -o "$git" = "git-bisect" || continue
 501                if test "$git" = "git-bisect"; then
 502                        rev="$command"
 503                        command="$bisect"
 504                fi
 505                case "$command" in
 506                start)
 507                        cmd="bisect_start $rev"
 508                        eval "$cmd" ;;
 509                good|bad|skip)
 510                        bisect_write "$command" "$rev" ;;
 511                *)
 512                        die "?? what are you talking about?" ;;
 513                esac
 514        done <"$1"
 515        bisect_auto_next
 516}
 517
 518bisect_run () {
 519    bisect_next_check fail
 520
 521    while true
 522    do
 523      echo "running $@"
 524      "$@"
 525      res=$?
 526
 527      # Check for really bad run error.
 528      if [ $res -lt 0 -o $res -ge 128 ]; then
 529          echo >&2 "bisect run failed:"
 530          echo >&2 "exit code $res from '$@' is < 0 or >= 128"
 531          exit $res
 532      fi
 533
 534      # Find current state depending on run success or failure.
 535      # A special exit code of 125 means cannot test.
 536      if [ $res -eq 125 ]; then
 537          state='skip'
 538      elif [ $res -gt 0 ]; then
 539          state='bad'
 540      else
 541          state='good'
 542      fi
 543
 544      # We have to use a subshell because "bisect_state" can exit.
 545      ( bisect_state $state > "$GIT_DIR/BISECT_RUN" )
 546      res=$?
 547
 548      cat "$GIT_DIR/BISECT_RUN"
 549
 550      if grep "first bad commit could be any of" "$GIT_DIR/BISECT_RUN" \
 551                > /dev/null; then
 552          echo >&2 "bisect run cannot continue any more"
 553          exit $res
 554      fi
 555
 556      if [ $res -ne 0 ]; then
 557          echo >&2 "bisect run failed:"
 558          echo >&2 "'bisect_state $state' exited with error code $res"
 559          exit $res
 560      fi
 561
 562      if grep "is first bad commit" "$GIT_DIR/BISECT_RUN" > /dev/null; then
 563          echo "bisect run success"
 564          exit 0;
 565      fi
 566
 567    done
 568}
 569
 570
 571case "$#" in
 5720)
 573    usage ;;
 574*)
 575    cmd="$1"
 576    shift
 577    case "$cmd" in
 578    help)
 579        git bisect -h ;;
 580    start)
 581        bisect_start "$@" ;;
 582    bad|good)
 583        bisect_state "$cmd" "$@" ;;
 584    skip)
 585        bisect_skip "$@" ;;
 586    next)
 587        # Not sure we want "next" at the UI level anymore.
 588        bisect_next "$@" ;;
 589    visualize|view)
 590        bisect_visualize "$@" ;;
 591    reset)
 592        bisect_reset "$@" ;;
 593    replay)
 594        bisect_replay "$@" ;;
 595    log)
 596        cat "$GIT_DIR/BISECT_LOG" ;;
 597    run)
 598        bisect_run "$@" ;;
 599    *)
 600        usage ;;
 601    esac
 602esac