Implement Unit Tests for Python Native to Engine Format Conversion

[badmonster0]

Enhancement

Add Unit test to convert.py for to_engine_value

Objective:

Develop unit tests to validate the functionality of the to_engine_value function, ensuring it accurately converts Python native data types into the engine-compatible format.​

Background:

• This module provide conversions between two data formats:
  • Values in Python native data types
  • Values in data structure exchangeable with cocoindex core engine (in Rust)
• Related issue for conversion from Engine to Python Format

The key difference is about how they handle Struct type

• In Python native data formats, it's represented by a dataclass (see the doc). Example: Order(order_id='O123', name='mixed nuts', price=25.0)

• In the exchangeable format with the core engine, it's a list of all fields. Example: ['O123', 'mixed nuts', 25.0]

Scope:

• The test need to cover different types:
  • Various basic types, struct types and collection types as listed in the doc
  • Composition of various types, e.g. list of struct, struct with list fields, struct with struct fields