Add unit tests for parsers

**Description**
Currently helpers lacks proper encryption support.

**Proposed solution**
Add configurable encryption with sensible defaults.

**Priority**: Low/Medium

Start by locating the helpers and parser entry points, then inspect the existing unit-test setup. Clarify whether the intended work is adding parser tests or implementing configurable encryption with defaults; done should include the agreed behavior and passing tests for it.

Written by the indexing model from the issue text.