[PATCH 2/2] bisect--helper: `check_expected_revs` shell function in C

[Pranit Bauva <pranit.bauva@gmail.com>]

Reimplement the `check_expected_revs` shell function in C and add a
`--check-expected-revs` subcommand to `git bisect--helper` to call it
from git-bisect.sh .

Using `--check-expected-revs` subcommand is a temporary measure to port
shell function in C so as to use the existing test suite. As more
functions are ported, this subcommand will be retired and will be called
by some other method namely `bisect_state()`.

Note: Previously is_expected_rev() was converted but not added as a
subcommand. Now since we have converted check_expected_rev() and we are
calling is_expected_rev()'s C implementation, we can safely delete the
shell implementation.

Mentored-by: Lars Schneider <larsxschneider@gmail.com>
Mentored-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Pranit Bauva <pranit.bauva@gmail.com>
---
 builtin/bisect--helper.c | 21 ++++++++++++++++++++-
 git-bisect.sh            | 20 ++------------------
 2 files changed, 22 insertions(+), 19 deletions(-)

diff --git a/builtin/bisect--helper.c b/builtin/bisect--helper.c
index 06bc9b8..500efd5 100644
--- a/builtin/bisect--helper.c
+++ b/builtin/bisect--helper.c
@@ -174,13 +174,28 @@ static int is_expected_rev(const char *expected_hex)
 	return !strcmp(actual_hex.buf, expected_hex);
 }
 
+static int check_expected_revs(const char **revs, int no)
+{
+	int i;
+
+	for (i = 0; i < no; i++) {
+		if (!is_expected_rev(revs[i])) {
+			remove_path(git_path_bisect_ancestors_ok());
+			remove_path(git_path_bisect_expected_rev());
+			return 0;
+		}
+	}
+	return 0;
+}
+
 int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
 {
 	enum {
 		NEXT_ALL = 1,
 		WRITE_TERMS,
 		BISECT_CLEAN_STATE,
-		BISECT_RESET
+		BISECT_RESET,
+		CHECK_EXPECTED_REVS
 	} cmdmode = 0;
 	int no_checkout = 0;
 	struct option options[] = {
@@ -192,6 +207,8 @@ int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
 			 N_("cleanup the bisection state"), BISECT_CLEAN_STATE),
 		OPT_CMDMODE(0, "bisect-reset", &cmdmode,
 			 N_("reset the bisection state"), BISECT_RESET),
+		OPT_CMDMODE(0, "check-expected-revs", &cmdmode,
+			 N_("check for expected revs"), CHECK_EXPECTED_REVS),
 		OPT_BOOL(0, "no-checkout", &no_checkout,
 			 N_("update BISECT_HEAD instead of checking out the current commit")),
 		OPT_END()
@@ -218,6 +235,8 @@ int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
 		if (argc > 1)
 			die(_("--bisect-reset requires either zero or one arguments"));
 		return bisect_reset(argc ? argv[0] : NULL);
+	case CHECK_EXPECTED_REVS:
+		return check_expected_revs(argv, argc);
 	default:
 		die("BUG: unknown subcommand '%d'", cmdmode);
 	}
diff --git a/git-bisect.sh b/git-bisect.sh
index 18580b7..4f6545e 100755
--- a/git-bisect.sh
+++ b/git-bisect.sh
@@ -238,22 +238,6 @@ bisect_write() {
 	test -n "$nolog" || echo "git bisect $state $rev" >>"$GIT_DIR/BISECT_LOG"
 }
 
-is_expected_rev() {
-	test -f "$GIT_DIR/BISECT_EXPECTED_REV" &&
-	test "$1" = $(cat "$GIT_DIR/BISECT_EXPECTED_REV")
-}
-
-check_expected_revs() {
-	for _rev in "$@"; do
-		if ! is_expected_rev "$_rev"
-		then
-			rm -f "$GIT_DIR/BISECT_ANCESTORS_OK"
-			rm -f "$GIT_DIR/BISECT_EXPECTED_REV"
-			return
-		fi
-	done
-}
-
 bisect_skip() {
 	all=''
 	for arg in "$@"
@@ -280,7 +264,7 @@ bisect_state() {
 		rev=$(git rev-parse --verify $(bisect_head)) ||
 			die "$(gettext "Bad rev input: $(bisect_head)")"
 		bisect_write "$state" "$rev"
-		check_expected_revs "$rev" ;;
+		git bisect--helper --check-expected-revs "$rev" ;;
 	2,"$TERM_BAD"|*,"$TERM_GOOD"|*,skip)
 		shift
 		hash_list=''
@@ -294,7 +278,7 @@ bisect_state() {
 		do
 			bisect_write "$state" "$rev"
 		done
-		check_expected_revs $hash_list ;;
+		git bisect--helper --check-expected-revs $hash_list ;;
 	*,"$TERM_BAD")
 		die "$(eval_gettext "'git bisect \$TERM_BAD' can take only one argument.")" ;;
 	*)
-- 
2.8.3