From a64d2aae5a593f4fb8b2020dc39556b256d1846e Mon Sep 17 00:00:00 2001
From: Jonathan Tan <jonathantanmy@google.com>
Date: Tue, 21 Jul 2020 15:50:20 -0700
Subject: sha1-file: make pretend_object_file() not prefetch

When pretend_object_file() is invoked with an object that does not exist
(as is the typical case), there is no need to fetch anything from the
promisor remote, because the caller already knows what the object is
supposed to contain. Therefore, suppress the fetch. (The
OBJECT_INFO_QUICK flag is added for the same reason.)

This was noticed at $DAYJOB when "blame" was run on a file that had
uncommitted modifications.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/sha1-file.c b/sha1-file.c
index 6168867..60765db 100644
--- a/sha1-file.c
+++ b/sha1-file.c
@@ -1589,7 +1589,8 @@ int pretend_object_file(void *buf, unsigned long len, enum object_type type,
 	struct cached_object *co;
 
 	hash_object_file(the_hash_algo, buf, len, type_name(type), oid);
-	if (has_object_file(oid) || find_cached_object(oid))
+	if (has_object_file_with_flags(oid, OBJECT_INFO_QUICK | OBJECT_INFO_SKIP_FETCH_OBJECT) ||
+	    find_cached_object(oid))
 		return 0;
 	ALLOC_GROW(cached_objects, cached_object_nr + 1, cached_object_alloc);
 	co = &cached_objects[cached_object_nr++];
diff --git a/t/t8002-blame.sh b/t/t8002-blame.sh
index eea048e..2ed6aaa 100755
--- a/t/t8002-blame.sh
+++ b/t/t8002-blame.sh
@@ -122,4 +122,15 @@ test_expect_success '--exclude-promisor-objects does not BUG-crash' '
 	test_must_fail git blame --exclude-promisor-objects one
 '
 
+test_expect_success 'blame with uncommitted edits in partial clone does not crash' '
+	git init server &&
+	echo foo >server/file.txt &&
+	git -C server add file.txt &&
+	git -C server commit -m file &&
+
+	git clone --filter=blob:none "file://$(pwd)/server" client &&
+	echo bar >>client/file.txt &&
+	git -C client blame file.txt
+'
+
 test_done
-- 
cgit v0.10.2-6-g49f6