Add test to run into issue with stack.len()

openssl/src/pkcs12.rs

@@ -196,6 +196,17 @@ mod test {
                    "c0cbdf7cdd03c9773e5468e1f6d2da7d5cbb1875");
     }
 
+    #[test]
+    fn parse_empty_chain() {
+        let der = include_bytes!("../test/keystore-empty-chain.p12");
+        let pkcs12 = Pkcs12::from_der(der).unwrap();
+        let parsed = pkcs12.parse("cassandra").unwrap();
+
+
+        assert_eq!(parsed.chain.len(), 0);
+        assert_eq!(parsed.chain.into_iter().collect::<Vec<_>>().len(), 0);
+    }
+
     #[test]
     fn create() {
         let subject_name = "ns.example.com";