Python TestCoverageGuard — Empty AI Test Interceptor

Test Integrity Interceptor Active

• Audit Status: WARNING. Phantom test structures and coverage manipulation detected.

Coverage Reality: 4/4 public functions are invoked (100% fake coverage), but critical verification logic is completely missing.

• Action Taken: Flagged empty assertions and fatal over-mocking configurations before code migration to staging.

Diagnostic Output (JSON Protocol)

{
  "audit_status": "WARNING",
  "coverage_summary": {
    "public_functions": 4,
    "covered": 4,
    "uncovered": 0
  },
  "findings": [
    {
      "type": "ERR_EMPTY_ASSERTION",
      "test": "test_calculate_tax",
      "line": 9,
      "detail": "Test has no assertion layer. The target function is called but the resulting payload is discarded.",
      "action_required": "Add explicit value-based verification: assert result == expected"
    },
    {
      "type": "ERR_OVER_MOCKING",
      "test": "test_generate_invoice",
      "line": 18,
      "detail": "The unit under test `generate_invoice` is mocked. The test validates the mock infrastructure, not the code logic.",
      "action_required": "Mock only external integration boundaries (db.save), never the function under test."
    }
  ],
  "audit_trail": {
    "timestamp": "2026-10-15T19:10:00Z",
    "verdict": "WARNING",
    "test_set_hash": "sha256:7f3a9e5d2b8c4a1f6e9d3b7c5a2f8e4d",
    "files_scanned": 1
  }
}

Optimization Steps & Explanations

Empty Assertion Detection (ERR_EMPTY_ASSERTION): Caught lazy AI behavior in test_calculate_tax on line 9. The assistant executed the billing computation to trick the coverage tool, but never validated the return values.
2.

Over-Mocking Audit (ERR_OVER_MOCKING): Isolated a critical logic trap in test_generate_invoice on line 18. The AI mocked the exact function it was supposed to test, essentially verifying a dummy placeholder instead of actual application physics.
3.

Air-Gapped Telemetry Verification: Analyzed the complete abstract syntax tree (AST) locally without triggering network dependencies, keeping internal billing code secure.