Add comprehensive test coverage for cuddZddSetop.c (86.61%)

[Copilot]

The test file for cuddZddSetop.c contained only a placeholder test. Added comprehensive test suite achieving 86.61% line coverage (375/433 executable lines), up from 6.5%.

Changes

• 19 test cases covering all 8 public API functions:

  • Cudd_zddIte, Cudd_zddUnion, Cudd_zddIntersect, Cudd_zddDiff
  • Cudd_zddDiffConst, Cudd_zddSubset1, Cudd_zddSubset0, Cudd_zddChange

• Test coverage includes:

  • All algorithmic branches (topf < v, topf > v, topf == v cases)
  • Edge cases with ZDD constants (empty set, base set)
  • Cache behavior validation
  • Deep recursion and complex nested operations
  • Constant node handling in intersect/diff operations

Uncovered Lines (13.39%)

Remaining uncovered lines are exceptional error paths:

• Timeout handlers (7 lines) - requires timeout infrastructure
• Memory allocation failures (51 lines) - requires OOM conditions

These standard CUDD error paths cannot be reliably triggered in unit tests without specialized mocking infrastructure.

Example Test Structure

TEST_CASE("cuddZddSetop - Cudd_zddIte basic tests") {
    DdManager* dd = Cudd_Init(4, 0, CUDD_UNIQUE_SLOTS, CUDD_CACHE_SLOTS, 0);
    
    SECTION("ITE with f = 0 returns h") {
        DdNode* result = Cudd_zddIte(dd, DD_ZERO(dd), z0, z1);
        REQUIRE(result == z1);
    }
    
    SECTION("ITE with g = h returns g") {
        DdNode* result = Cudd_zddIte(dd, z0, z1, z1);
        REQUIRE(result == z1);
    }
    // ... more test sections
}

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• esm.ubuntu.com
  • Triggering command: /usr/lib/apt/methods/https /usr/lib/apt/methods/https (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

Complete test cases for src/cuddZddSetop.c and target 90% coverage for the source file.

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