Add fact parser validation, tests, and bulk fact loading with tests

[ColtonPayne]

Summary

This PR adds comprehensive input validation to the fact parser and implements bulk fact loading from CSV files with extensive test coverage.

Fact Parser Validation (fact_parser.py) (Issue #91 )

• Added validation for empty/whitespace-only input
• Validates parentheses structure and placement (Issue BUG-038: Missing Parenthesis Validation - Causes Silent Data Corruption in Fact Parser #89 )
• Enforces valid predicate naming (must start with letter or underscore, alphanumeric + underscore allowed)
• Validates component structure (no nested parentheses, colons, etc.)
• Validates interval bounds are within [0, 1] range and are in the proper format (issue BUG-039: No Validation for Interval Bound Format - Crashes on Malformed Input #90 )
• Validates interval lower <= upper bound
• Prevents double negation and negation with explicit bounds
• Provides clear, specific error messages for each validation failure

Bulk Fact Loading (pyreason.py)

• Implemented add_fact_in_bulk() function to load facts from CSV files
• Supports optional header row detection
• Handles optional columns: name, start_time, end_time, static
• Provides warnings for invalid data (malformed facts, invalid times, etc.) without crashing
• Supports multiple boolean formats for static field (True/true/1/yes, False/false/0/no)

Test Coverage

• 333 new lines in test_fact_parser.py:
  • Tests for valid fact parsing (node/edge facts, intervals, negation, etc.)
  • Tests for invalid inputs (missing parentheses, empty fields, invalid characters, etc.)
  • Edge cases and boundary conditions
• 204 new lines in test_pyreason_file_loading.py:
  • Tests for bulk fact loading from CSV
  • Warning validation for invalid facts
  • Tests with/without headers, various static value formats
  • Error handling tests

Test Data

• Created example_facts.csv with comprehensive test scenarios including both valid and invalid facts
• Created example_facts_no_header.csv for testing CSV without headers

Implementation Notes

• All validation errors raise ValueError with descriptive messages
• Bulk loading continues processing even when individual rows fail (with warnings)
• Predicate validation regex: ^[a-zA-Z_][a-zA-Z0-9_]*$ (follows Python identifier rules)

🤖 Generated with Claude Code

[dyumanaditya]

@ColtonPayne Everything looks good except for my one comment on explicit bound inverses.

[dyumanaditya]

negation with explicit bound This should actually be allowed. The negation of an explicit bound is defined and has an explicit formula. Currently it is not supported but it needs to be.

The formula for the inverse of a bound [l, u] is: ~[l, u] = [1-u, 1-l]

[kmukherji]

Some more comments are inline.

[kmukherji]

Once these comments are addressed we can merge this branch.

[kmukherji]

I think we can resolve end_time errors by assigning end_time = start_time.
What do you think?

[ColtonPayne]

We are currently handling invalid values for start_time and end_time by setting them to zero if the user passes a non-integer value. This is the default value provided by the Fact constructor.

 # Parse start_time
    try:
        start_time = int(start_time_raw) if start_time_raw is not None and str(start_time_raw).strip() else 0

If raise_errors is false, we handle this gracefully. If raise_errors is true, we will not accept an invalid json/csv and force the user to correct the bad input.

[kmukherji]

Yeah. I am talking about the specific case where start_time is a valid non-zero integer. But end_time has an error. Should we give a warning and set it to start_time?

Completed