Merge branch 'cc/bisect-rev-parsing'

The logic in "git bisect bad HEAD" etc. to avoid forcing the test
of the common ancestor of bad and good commits was broken.

* cc/bisect-rev-parsing:
  bisect: add test to check that revs are properly parsed
  bisect: parse revs before passing them to check_expected_revs()

Author: gitster

git-bisect.sh

@@ -237,15 +237,18 @@ bisect_state() {
 		check_expected_revs "$rev" ;;
 	2,bad|*,good|*,skip)
 		shift
-		eval=''
+		hash_list=''
 		for rev in "$@"
 		do
 			sha=$(git rev-parse --verify "$rev^{commit}") ||
 				die "$(eval_gettext "Bad rev input: \$rev")"
-			eval="$eval bisect_write '$state' '$sha'; "
+			hash_list="$hash_list $sha"
 		done
-		eval "$eval"
-		check_expected_revs "$@" ;;
+		for rev in $hash_list
+		do
+			bisect_write "$state" "$rev"
+		done
+		check_expected_revs $hash_list ;;
 	*,bad)
 		die "$(gettext "'git bisect bad' can take only one argument.")" ;;
 	*)

t/t6030-bisect-porcelain.sh

@@ -779,4 +779,13 @@ test_expect_success 'bisect log: only skip commits left' '
 	git bisect reset
 '
 
+test_expect_success '"git bisect bad HEAD" behaves as "git bisect bad"' '
+	git checkout parallel &&
+	git bisect start HEAD $HASH1 &&
+	git bisect good HEAD &&
+	git bisect bad HEAD &&
+	test "$HASH6" = $(git rev-parse --verify HEAD) &&
+	git bisect reset
+'
+
 test_done