Fixes libgit2#962: First create a git_patch to get delta->flags correctly

Author: yoichi

src/diff.c

@@ -505,6 +505,17 @@ PyTypeObject DiffIterType = {
 PyObject *
 diff_get_delta_byindex(git_diff *diff, size_t idx)
 {
+    git_patch *patch = NULL;
+    int err;
+
+    /* create a git_patch in order to store delta->flags */
+    err = git_patch_from_diff(&patch, diff, idx);
+    if (err < 0) {
+        PyErr_SetObject(PyExc_IndexError, PyLong_FromSize_t(idx));
+        return NULL;
+    }
+    git_patch_free(patch);
+
     const git_diff_delta *delta = git_diff_get_delta(diff, idx);
     if (delta == NULL) {
         PyErr_SetObject(PyExc_IndexError, PyLong_FromSize_t(idx));

test/test_diff.py

@@ -319,9 +319,7 @@ def test_deltas(barerepo):
         assert delta.nfiles == patch_delta.nfiles
         assert delta.old_file.id == patch_delta.old_file.id
         assert delta.new_file.id == patch_delta.new_file.id
-
-        # As explained in the libgit2 documentation, flags are not set
-        #assert delta.flags == patch_delta.flags
+        assert delta.flags == patch_delta.flags
 
 def test_diff_parse(barerepo):
     diff = pygit2.Diff.parse_diff(PATCH)