diff: When diffing two blobs, ensure the delta callback parameter is filled with…

diff: When diffing two blobs, ensure the delta callback parameter is filled with relevant information

src/diff_output.c

@@ -728,12 +728,16 @@ int git_diff_blobs(
 	delta.status = old_data.ptr ?
 		(new_data.ptr ? GIT_DELTA_MODIFIED : GIT_DELTA_DELETED) :
 		(new_data.ptr ? GIT_DELTA_ADDED : GIT_DELTA_UNTRACKED);
-	delta.old_file.mode = 0100644; /* can't know the truth from a blob alone */
-	delta.new_file.mode = 0100644;
+	delta.old_file.mode = 0000000; /* can't know the truth from a blob alone */
+	delta.new_file.mode = 0000000;
 	git_oid_cpy(&delta.old_file.oid, git_object_id((const git_object *)old_blob));
 	git_oid_cpy(&delta.new_file.oid, git_object_id((const git_object *)new_blob));
 	delta.old_file.path = NULL;
 	delta.new_file.path = NULL;
+	delta.old_file.size = old_data.size;
+	delta.new_file.size = new_data.size;
+	delta.old_file.flags = 0;
+	delta.new_file.flags = 0;
 	delta.similarity = 0;
 
 	info.diff    = NULL;

tests-clar/diff/blob.c

@@ -13,7 +13,7 @@ void test_diff_blob__cleanup(void)
 	cl_git_sandbox_cleanup();
 }
 
-void test_diff_blob__0(void)
+void test_diff_blob__can_compare_text_blobs(void)
 {
 	git_blob *a, *b, *c, *d;
 	git_oid a_oid, b_oid, c_oid, d_oid;