diff --git a/src/applications/diffusion/conduit/DiffusionDiffQueryConduitAPIMethod.php b/src/applications/diffusion/conduit/DiffusionDiffQueryConduitAPIMethod.php
--- a/src/applications/diffusion/conduit/DiffusionDiffQueryConduitAPIMethod.php
+++ b/src/applications/diffusion/conduit/DiffusionDiffQueryConduitAPIMethod.php
@@ -153,7 +153,7 @@
     $arcanist_changes = DiffusionPathChange::convertToArcanistChanges(
       $path_changes);
 
-    $parser = $this->getDefaultParser();
+    $parser = $this->getDefaultParser($request);
     $parser->setChanges($arcanist_changes);
     $parser->forcePath($path->getPath());
     $changes = $parser->parseDiff($raw_diff);