Fix crash on functions with complex type hints #129

[MahmoodAbuGneam]

Fix crash on functions with complex type hints

Fixes #129

Problem

Bowler currently crashes when attempting to process functions that have complex type hints (e.g., typing.List[str]). The error occurs because the code attempts to access the .value attribute of a Node object that represents the type hint, but complex type hints are represented as nested Node objects rather than simple values.

Solution

I modified how FunctionArgument handles type annotations by:

1. Storing the entire AST node for type hints instead of just its value
2. Adding proper handling for different annotation types (Node, str, Leaf)
3. Implementing safe cloning of complex type hint nodes

Changes

• In bowler/imr.py:

  • Updated FunctionArgument.build() to store complete annotation nodes
  • Enhanced FunctionArgument.explode() to handle all annotation types
  • Added proper node cloning to preserve type hint structure

• In bowler/tests/query.py:

  • Added comprehensive test suite for type hint handling
  • Test coverage includes:
    • Basic complex types (List[str])
    • Nested type hints (Dict[str, List[int]])
    • Multiple type hints in same function
    • Modifying existing type hints

Testing

✅ All tests pass
✅ Code formatted with black and isort
✅ New test cases added to verify the fix

Example

Before this fix:

def process_items(items: typing.List[str]): pass
# ❌ Would crash when trying to modify this function

After this fix :

def process_items(items: typing.List[str]): pass
# ✅ Can now safely:
# - Add new arguments
# - Modify type hints
# - Handle nested type hints

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