[PATCH v3] bisect: teach "skip" to accept a range using "-r|--range" option

@@ -19,7 +19,7 @@ on the subcommand:
  git bisect start [<bad> [<good>...]] [--] [<paths>...]
  git bisect bad [<rev>]
  git bisect good [<rev>...]
- git bisect skip [<rev>...]
+ git bisect skip [(<rev>|<range>)...]
  git bisect reset [<branch>]
  git bisect visualize
  git bisect replay <logfile>

@@ -164,6 +164,34 @@ But computing the commit to test may be slower afterwards and git may
 eventually not be able to tell the first bad among a bad and one or
 more "skip"ped commits.
 
+You can even skip a range of commits, instead of just one commit,
+using option -r|--range. For example:
+
+------------
+$ git bisect skip --range=v2.5,v2.6
+------------
+
+or:
+
+------------
+$ git bisect skip -r v2.5,v2.6
+------------
+
+would mean that no commit between versions 2.5 included and 2.6
+included can be tested.
+
+Note that you must take care that the first commit in the given range
+is an ancestor of the second commit.
+
+Also note that if you don't want to skip the first commit of a range
+you can use something like:
+
+------------
+$ git bisect skip $(git rev-list v2.5..v2.6)
+------------
+
+and the commit pointed to by v2.5 will not be skipped.
+
 Cutting down bisection by giving more parameters to bisect start
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

@@ -9,7 +9,7 @@ git bisect bad [<rev>]
         mark <rev> a known-bad revision.
 git bisect good [<rev>...]
         mark <rev>... known-good revisions.
-git bisect skip [<rev>...]
+git bisect skip [(<rev>|<range>)...]
         mark <rev>... untestable revisions.
 git bisect next
         find next bisection to test and check it out.

@@ -191,6 +191,52 @@ check_expected_revs() {
 	done
 }
 
+list_range() {
+	case "$1" in
+	*,*) ;; # Ok
+	*) die "Bad range: $1" ;;
+	esac
+
+	_A=$(expr "z$1" : 'z\([^,]*\),.*')
+	_B=$(expr "z$1" : 'z[^,]*,\(.*\)')
+
+	#
+	# We want a range with both bounds included.
+	# ("git rev-list ^A B" would exclude commit A.)
+	# This means we want to exclude starting from the parents of _A,
+	# not starting from _A itself.
+	#
+	git rev-list "${_B:-HEAD}" --not $(git rev-parse "${_A:-HEAD}^@")
+}
+
+bisect_skip() {
+        all=''
+	while test $# != 0
+	do
+		case "$1" in
+		-r|--range*)
+			case "$#,$1" in
+			*,*=*)
+				range=$(expr "z$1" : 'z-[^=]*=\(.*\)') ;;
+			1,*)
+				die "Bad or incomplete range: $1" ;;
+			*)
+				range="$2"; shift ;;
+			esac
+			revs=$(list_range "$range") ||
+				die "Bad rev input: $1"
+			;;
+		*)
+			revs="'$arg'"
+			;;
+		esac
+		shift
+		all="$all $revs"
+        done
+        bisect_state 'skip' $all
+}
+
+
 bisect_state() {
 	bisect_autostart
 	state=$1

@@ -630,8 +676,10 @@ case "$#" in
         git bisect -h ;;
     start)
         bisect_start "$@" ;;
-    bad|good|skip)
+    bad|good)
         bisect_state "$cmd" "$@" ;;
+    skip)
+        bisect_skip "$@" ;;
     next)
         # Not sure we want "next" at the UI level anymore.
         bisect_next "$@" ;;

@@ -313,8 +313,16 @@ test_expect_success 'bisect run & skip: find first bad' '
 	grep "$HASH6 is first bad commit" my_bisect_log.txt
 '
 
-test_expect_success 'bisect starting with a detached HEAD' '
+test_expect_success 'bisect skip range' '
+	git bisect reset &&
+	git bisect start $HASH7 $HASH1 &&
+	git bisect skip --range=$HASH2,$HASH5 &&
+	test "$HASH6" = "$(git rev-parse --verify HEAD)" &&
+	test_must_fail git bisect bad > my_bisect_log.txt &&
+	grep "first bad commit could be any of" my_bisect_log.txt
+'
 
+test_expect_success 'bisect starting with a detached HEAD' '
 	git bisect reset &&
 	git checkout master^ &&
 	HEAD=$(git rev-parse --verify HEAD) &&