[PATCH v3 1/2] blame: Allow to blame paths freshly added to the index

[Mike Hommey <mh@glandium.org>]

When blaming files, changes in the work tree are taken into account
and displayed as being "Not Committed Yet".

However, when blaming a file that is not known to the current HEAD,
git blame fails with `no such path 'foo' in HEAD`, even when the file
was git add'ed.

This would seem uninteresting with the plain `git blame` case, which
it is, but it becomes useful when using copy detection, and the new file
was created from pieces already in HEAD, moved or copied from other
files.

Signed-off-by: Mike Hommey <mh@glandium.org>
---
 builtin/blame.c               | 10 +++++++++-
 t/t8003-blame-corner-cases.sh | 45 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 54 insertions(+), 1 deletion(-)

diff --git a/builtin/blame.c b/builtin/blame.c
index 1e214bd..f297a7f 100644
--- a/builtin/blame.c
+++ b/builtin/blame.c
@@ -2230,6 +2230,7 @@ static int git_blame_config(const char *var, const char *value, void *cb)
 static void verify_working_tree_path(struct commit *work_tree, const char *path)
 {
 	struct commit_list *parents;
+	int pos;
 
 	for (parents = work_tree->parents; parents; parents = parents->next) {
 		const unsigned char *commit_sha1 = parents->item->object.oid.hash;
@@ -2240,7 +2241,14 @@ static void verify_working_tree_path(struct commit *work_tree, const char *path)
 		    sha1_object_info(blob_sha1, NULL) == OBJ_BLOB)
 			return;
 	}
-	die("no such path '%s' in HEAD", path);
+
+	pos = cache_name_pos(path, strlen(path));
+	if (pos >= 0)
+		; /* path is in the index */
+	else if (!strcmp(active_cache[-1 - pos]->name, path))
+		; /* path is in the index, unmerged */
+	else
+		die("no such path '%s' in HEAD", path);
 }
 
 static struct commit_list **append_parent(struct commit_list **tail, const unsigned char *sha1)
diff --git a/t/t8003-blame-corner-cases.sh b/t/t8003-blame-corner-cases.sh
index a9b266f..eab2e28 100755
--- a/t/t8003-blame-corner-cases.sh
+++ b/t/t8003-blame-corner-cases.sh
@@ -137,6 +137,51 @@ test_expect_success 'blame wholesale copy and more' '
 
 '
 
+test_expect_success 'blame wholesale copy and more in the index' '
+
+	cat >horse <<-\EOF &&
+	ABC
+	DEF
+	XXXX
+	YYYY
+	GHIJK
+	EOF
+	git add horse &&
+	test_when_finished "git rm -f horse" &&
+	git blame -f -C -C1 -- horse | sed -e "$pick_fc" >current &&
+	cat >expected <<-\EOF &&
+	mouse-Initial
+	mouse-Second
+	cow-Fifth
+	horse-Not
+	mouse-Third
+	EOF
+	test_cmp expected current
+
+'
+
+test_expect_success 'blame during cherry-pick with file rename conflict' '
+
+	test_when_finished "git reset --hard && git checkout master" &&
+	git checkout HEAD~3 &&
+	echo MOUSE >> mouse &&
+	git mv mouse rodent &&
+	git add rodent &&
+	GIT_AUTHOR_NAME=Rodent git commit -m "rodent" &&
+	git checkout --detach master &&
+	(git cherry-pick HEAD@{1} || test $? -eq 1) &&
+	git show HEAD@{1}:rodent > rodent &&
+	git add rodent &&
+	git blame -f -C -C1 rodent | sed -e "$pick_fc" >current &&
+	cat current &&
+	cat >expected <<-\EOF &&
+	mouse-Initial
+	mouse-Second
+	rodent-Not
+	EOF
+	test_cmp expected current
+'
+
 test_expect_success 'blame path that used to be a directory' '
 	mkdir path &&
 	echo A A A A A >path/file &&
-- 
2.9.1.277.gdbc86c9.dirty