fix path_test's portability

Author: jackcmay

src/dynamic_contract.rs

@@ -109,13 +109,16 @@ mod tests {
     use bincode::serialize;
     use hash::Hash;
     use signature::Signature;
+    use std::path::Path;
 
     #[test]
     fn test_create_library_path_1() {
-        assert_eq!(
-            "target/debug/deps/libfoo.dylib",
-            create_library_path("foo").to_str().unwrap()
-        );
+        let path = create_library_path("noop");
+        assert_eq!(true, Path::new(&path).exists());
+        let path = create_library_path("print");
+        assert_eq!(true, Path::new(&path).exists());
+        let path = create_library_path("move_funds");
+        assert_eq!(true, Path::new(&path).exists());
     }
 
     #[test]