fix bug

Author: ravilushqa

cmd/description/main.go

@@ -138,6 +138,9 @@ func genCompletionPerFile(ctx context.Context, client *oAIClient.Client, diff *g
 	OverallDescribeCompletion := fmt.Sprintf("Pull request title: %s, body: %s\n\n", pr.GetTitle(), pr.GetBody())
 
 	for i, file := range diff.Files {
+		if file.Patch == nil {
+			continue
+		}
 		prompt := fmt.Sprintf(oAIClient.PromptDescribeChanges, *file.Patch)
 
 		if len(prompt) > 4096 {