LANG-1834 Fix Fraction reduction for Integer.MIN_VALUE

[makarandhinge]

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Fix Fraction.getReducedFraction handling for Integer.MIN_VALUE with a negative denominator.

When the numerator is Integer.MIN_VALUE and the denominator is negative, the current implementation can attempt to negate Integer.MIN_VALUE, which overflows and throws an ArithmeticException even when the fraction can be reduced to a valid integer fraction.

This change reduces common powers of two from the numerator and denominator before sign normalization, avoiding the overflow for representable fractions while preserving overflow handling for results that cannot be represented as int.

Tests

Added regression coverage for:

• Integer.MIN_VALUE / -2
• Integer.MIN_VALUE / -6
• Integer.MIN_VALUE / Integer.MIN_VALUE
• Integer.MIN_VALUE / -1 (overflow)
• Integer.MIN_VALUE / -3 (overflow)

All existing FractionTest tests continue to pass.

[Copilot]

🟢 Approval recommended

The reviewed changes address the overflow case with regression coverage.

Pull request overview

Fixes Fraction.getReducedFraction handling for Integer.MIN_VALUE with negative denominators.

Changes:

• Reduces common powers of two before sign normalization.
• Adds regression tests for representable and overflowing edge cases.

File summaries

File	Summary
src/test/java/org/apache/commons/lang3/math/FractionTest.java	Adds boundary-value regression coverage.
src/main/java/org/apache/commons/lang3/math/Fraction.java	Updates fraction reduction logic to avoid overflow.

Review details

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

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[garydgregory]

@makarandhinge Thank you, merged 🚀