stat_tracking_info(): clear object flags used during counting

When left-right traversal counts the commits in a diverged history, it
leaves the flags in the commits smudged, and we need to clear them before
we return.  Otherwise the caller cannot inspect other branches with this
function again.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

3 files changed, 75 insertions, 0 deletions

diff --git a/remote.c b/remote.c
index bd5c3be3ec..df8bd72ba9 100644
--- a/remote.c
+++ b/remote.c
@@ -1295,6 +1295,10 @@ int stat_tracking_info(struct branch *branch, int *num_ours, int *num_theirs)
 		else
 			(*num_theirs)++;
 	}
+
+	/* clear object flags smudged by the above traversal */
+	clear_commit_marks(ours, ALL_REV_FLAGS);
+	clear_commit_marks(theirs, ALL_REV_FLAGS);
 	return 1;
 }
 
diff --git a/revision.h b/revision.h
index abce5001f1..e8bac6d141 100644
--- a/revision.h
+++ b/revision.h
@@ -11,6 +11,7 @@
 #define ADDED		(1u<<7)	/* Parents already parsed and added? */
 #define SYMMETRIC_LEFT	(1u<<8)
 #define TOPOSORT	(1u<<9)	/* In the active toposort list.. */
+#define ALL_REV_FLAGS	((1u<<10)-1)
 
 struct rev_info;
 struct log_info;
diff --git a/t/t6040-tracking-info.sh b/t/t6040-tracking-info.sh
new file mode 100755
index 0000000000..aac212e936
--- /dev/null
+++ b/t/t6040-tracking-info.sh
@@ -0,0 +1,70 @@
+#!/bin/sh
+
+test_description='remote tracking stats'
+
+. ./test-lib.sh
+
+advance () {
+	echo "$1" >"$1" &&
+	git add "$1" &&
+	test_tick &&
+	git commit -m "$1"
+}
+
+test_expect_success setup '
+	for i in a b c;
+	do
+		advance $i || break
+	done &&
+	git clone . test &&
+	(
+		cd test &&
+		git checkout -b b1 origin &&
+		git reset --hard HEAD^ &&
+		advance d &&
+		git checkout -b b2 origin &&
+		git reset --hard b1 &&
+		git checkout -b b3 origin &&
+		git reset --hard HEAD^ &&
+		git checkout -b b4 origin &&
+		advance e &&
+		advance f
+	)
+'
+
+script='s/^..\(b.\)[	 0-9a-f]*\[\([^]]*\)\].*/\1 \2/p'
+cat >expect <<\EOF
+b1 ahead 1, behind 1
+b2 ahead 1, behind 1
+b3 behind 1
+b4 ahead 2
+EOF
+
+test_expect_success 'branch -v' '
+	(
+		cd test &&
+		git branch -v
+	) |
+	sed -n -e "$script" >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'checkout' '
+	(
+		cd test && git checkout b1
+	) >actual &&
+	grep -e "have 1 and 1 different" actual
+'
+
+test_expect_success 'status' '
+	(
+		cd test &&
+		git checkout b1 >/dev/null &&
+		# reports nothing to commit
+		test_must_fail git status
+	) >actual &&
+	grep -e "have 1 and 1 different" actual
+'
+
+
+test_done