diff --git a/kallithea/controllers/pullrequests.py b/kallithea/controllers/pullrequests.py
--- a/kallithea/controllers/pullrequests.py
+++ b/kallithea/controllers/pullrequests.py
@@ -592,23 +592,22 @@ class PullrequestsController(BaseRepoCon
         log.debug('running diff between %s and %s in %s',
                   c.a_rev, c.cs_rev, org_scm_instance.path)
         try:
-            txtdiff = org_scm_instance.get_diff(rev1=safe_str(c.a_rev), rev2=safe_str(c.cs_rev),
+            raw_diff = org_scm_instance.get_diff(rev1=safe_str(c.a_rev), rev2=safe_str(c.cs_rev),
                                                 ignore_whitespace=ignore_whitespace,
                                                 context=line_context)
         except ChangesetDoesNotExistError:
-            txtdiff = _("The diff can't be shown - the PR revisions could not be found.")
-        diff_processor = diffs.DiffProcessor(txtdiff or '', diff_limit=diff_limit)
-        _parsed = diff_processor.prepare()
+            raw_diff = _("The diff can't be shown - the PR revisions could not be found.")
+        diff_processor = diffs.DiffProcessor(raw_diff or '', diff_limit=diff_limit)
 
         c.limited_diff = False
-        if isinstance(_parsed, LimitedDiffContainer):
+        if isinstance(diff_processor.parsed, LimitedDiffContainer):
             c.limited_diff = True
 
         c.file_diff_data = []
         c.lines_added = 0
         c.lines_deleted = 0
 
-        for f in _parsed:
+        for f in diff_processor.parsed:
             st = f['stats']
             c.lines_added += st['added']
             c.lines_deleted += st['deleted']