Add validation for unbalanced parentheses in rules

[Giulia Stocco (gfs)]

No description provided.

[Copilot]

Pull request overview

Adds additional validation to detect unbalanced parentheses in rule expressions during analysis, and extends unit coverage to catch a previously-accepted malformed expression.

Changes:

• Add a post-parse validation in Analyzer.EnumerateRuleIssues(Rule rule) to flag expressions with unmatched parentheses counts.
• Add a unit test case for an expression with an opening parenthesis attached to a token (e.g., "(0 AND 1").

Show a summary per file

File	Description
OAT/Analyzer.cs	Adds an end-of-parse check intended to detect unbalanced parentheses in rule expressions.
OAT.Tests/ExpressionsTests.cs	Adds a regression test for a rule expression with an unmatched opening parenthesis without a separating space.

Review details

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• Files reviewed: 2/2 changed files
• Comments generated: 1
• Review effort level: Lite

[Copilot]

Review details

Suppressed comments (2)

OAT/Analyzer.cs:398

• The new unbalanced-parentheses validation only checks total '(' vs ')' counts. This misses expressions where parentheses close before they open but totals still match (e.g. 0) AND (1), which can currently pass validation. Consider also rejecting any expression where the running parentheses balance ever goes negative, while still keeping the end-of-expression count check.

                if (foundStarts != foundEnds)
                {
                    yield return new Violation(string.Format(Strings.Get("Err_ClauseUnbalancedParentheses"), expression, rule.Name), rule);
                }

OAT.Tests/ExpressionsTests.cs:438

• Tests cover extra opening/closing parentheses, but not the case where the total counts match while the order is invalid (a close before any open), which is an easy regression to miss (e.g. 0) AND (1). Adding a case here will lock in the intended validation behavior.

            Assert.False(analyzer.IsRuleValid(invalidRule));

            invalidRule = new Rule("UnbalancedOpenParentheses")
            {
                Expression = "(0 AND 1",

• Files reviewed: 2/2 changed files
• Comments generated: 0 new
• Review effort level: Lite