Create a custom MyEventEmitter class that mimics the behavior of Node.js EventEmitter. Implement the following methods:

1. on: Adds a listener to the end of the listeners array for the specified event.
2. once: Adds a one-time listener for the event. The listener is invoked only the next time the event is fired, after which it is removed.
3. off: Removes the specified listener from the listener array for the specified event.
4. emit: Synchronously calls each of the listeners registered for the event, in the order they were registered, passing the supplied arguments to each.
5. prependListener: Adds a listener to the beginning of the listeners array for the specified event.
6. prependOnceListener: Adds a one-time listener for the event to the beginning of the listeners array. The listener is invoked only the next time the event is fired, after which it is removed.
7. removeAllListeners: Remove all listeners for a specific event, or all events if no event is specified.
8. listenerCount: Returns the number of listeners for a given event.

• Follow the JavaScript task guideline before starting.
• Implement a solution by creating a class MyEventEmitter that includes the required methods.
• Make sure to handle edge cases, such as removing a non-existent listener or emitting an event with no listeners registered.
• Test your implementation with various scenarios to ensure correctness.

Note: This task does not require any external libraries or modules. You should implement the EventEmitter from scratch using only built-in JavaScript features.