Fix bugs in new diff patch code

This fixes all the bugs in the new diff patch code.  The only
really interesting one is that when we merge two diffs, we now
have to actually exclude diff delta records that are not supposed
to be tracked, as opposed to before where they could be included
because they would be skipped silently by `git_diff_foreach()`.
Other than that, there are just minor errors.

1 files changed, 7 insertions, 5 deletions

diff --git a/tests-clar/diff/diffiter.c b/tests-clar/diff/diffiter.c
index 9e33d91e1..4273b16dd 100644
--- a/tests-clar/diff/diffiter.c
+++ b/tests-clar/diff/diffiter.c
@@ -256,21 +256,23 @@ void test_diff_diffiter__iterate_all(void)
 
 	cl_assert_equal_i(13, exp.files);
 	cl_assert_equal_i(8, exp.hunks);
-	cl_assert_equal_i(13, exp.lines);
+	cl_assert_equal_i(14, exp.lines);
 
 	git_diff_list_free(diff);
 }
 
 static void iterate_over_patch(git_diff_patch *patch, diff_expects *exp)
 {
-	size_t h, num_h = git_diff_patch_num_hunks(patch);
+	size_t h, num_h = git_diff_patch_num_hunks(patch), num_l;
 
 	exp->files++;
 	exp->hunks += num_h;
 
 	/* let's iterate in reverse, just because we can! */
-	for (h = 1; h <= num_h; ++h)
-		exp->lines += git_diff_patch_num_lines_in_hunk(patch, num_h - h);
+	for (h = 1, num_l = 0; h <= num_h; ++h)
+		num_l += git_diff_patch_num_lines_in_hunk(patch, num_h - h);
+
+	exp->lines += num_l;
 }
 
 #define PATCH_CACHE 5
@@ -338,5 +340,5 @@ void test_diff_diffiter__iterate_randomly_while_saving_state(void)
 	/* hopefully it all still added up right */
 	cl_assert_equal_i(13, exp.files);
 	cl_assert_equal_i(8, exp.hunks);
-	cl_assert_equal_i(13, exp.lines);
+	cl_assert_equal_i(14, exp.lines);
 }