Better handling of None value when formatting XuleValue value

[aaroncameron-wk]

Description

XuleValue.format_value will throw an error for most value types when calling format_value with a self.value of None.

Example stacktrace:

Traceback (most recent call last):
File "/usr/local/lib/python3.12/site-packages/xule/XuleProcessor.py", line 252, in evaluate_rule_set
    evaluate(rule, xule_context)
File "/usr/local/lib/python3.12/site-packages/xule/XuleProcessor.py", line 643, in evaluate
    value = EVALUATOR[rule_part_name](rule_part, xule_context)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/site-packages/xule/XuleProcessor.py", line 920, in evaluate_assertion
    messages[rule_result[\'resultName\']] = result_message(assert_rule, rule_result, xule_value,
                                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/site-packages/xule/XuleProcessor.py", line 5294, in result_message
    message_value = evaluate(result_ast[\'resultExpr\'], message_context)
                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/site-packages/xule/XuleProcessor.py", line 643, in evaluate
    value = EVALUATOR[rule_part_name](rule_part, xule_context)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/site-packages/xule/XuleProcessor.py", line 1202, in evaluate_string_literal
    expr_value = evaluate(string_item, xule_context)
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/site-packages/xule/XuleProcessor.py", line 643, in evaluate
    value = EVALUATOR[rule_part_name](rule_part, xule_context)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/site-packages/xule/XuleProcessor.py", line 4452, in evaluate_property
    object_value = process_property(current_property_expr, object_value, property_info, xule_context)
                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/site-packages/xule/XuleProcessor.py", line 4530, in process_property
    object_value = property_info[XuleProperties.PROP_FUNCTION](xule_context, object_value, *arg_values)
                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/site-packages/xule/XuleProperties.py", line 381, in property_join
    result_string += next_sep + k.format_value() + pair_sep.value + v.format_value()
                                                                    ^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/site-packages/xule/XuleValue.py", line 520, in format_value
    return str(self.value.qname)
               ^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'qname'

@campbellpryde
@davidtauriello

[phillipengel]

This fix will fix the symptom, BUT, a XuleValue.value should not be None if its type is not 'none'. So, I think the real problem lies elsewhere. Can you provide an example that causes this error?

[aaroncameron-wk]

Can you provide an example that causes this error?

Unfortunately the document that triggered this is a pre-release filing which I can not easily obtain access to, nor do I have the knowledge to create an example myself. It may very well be that the document was in a very poor/incomplete state, in which case it would be preferable to have format_value be hardened so that the issue can be captured and reported elsewhere.

[davidtauriello]

@aaroncameron-wk - this was addressed in release 30047