rdmsm4x-changelog-20260905-1142-ramdisk-m4-it7-settling-probe-isolation

Settling probe hardening, APFS synthesized container discovery, and multi-run test isolation implemented and verified across macOS-ramDisk-app on canonical rdmsm4x.

Scope

• Repository: canonical rdmsm4x:~/dev/apps/macOS-ramDisk-app/
• Commit: 786c175
• Files touched:
  • Sources/RAMDiskCore/StoragePrimitive.swift
  • Tests/E2ETests/e2e_framework.py
  • Tests/E2ETests/run_e2e_tests.sh

Changes Made

1. Sources/RAMDiskCore/StoragePrimitive.swift:
   • Settling probe: verify FileManager.default.fileExists(atPath: cleanDev) before querying size. Add fallback probe with 200ms backoff if device node is present but settling. Add 2.0s settling pause before retrying eraseDisk if error contains "Could not find disk".
   • Post-mount collision rejection: dynamically extend verifyDeadline = max(verifyDeadline, Date().addingTimeInterval(5.0)), add 150ms pause after clearMountPathStub, and pass -mountPoint targetMountPath if directory exists (falling back to bare diskutil mount <volumeDev> if absent).
   • resolveAllDeviceEntities: query diskutil apfs list -plist to discover synthesized APFS containers and volumes mapped to the RAM disk physical store (PhysicalStores), ensuring child APFS containers are unmounted and ejected before parent disk ejection.
2. Tests/E2ETests/e2e_framework.py:
   • Added post-drain verification and emergency fallback loop in ensure_unmounted().
3. Tests/E2ETests/run_e2e_tests.sh:
   • Added pre-tier and post-tier verification barriers in run_tier().
   • Added post-suite cleanup_ramdisks.

Verification Evidence

• AST Invariants: All 6 literal strings pass with exit code 0.
• swift build: 0 errors, 0 warnings.
• swift test: 4/4 Modern Testing Library tests pass.
• swift test --sanitize=thread: 0 data races, exit code 0.
• 15-cycle rapid stress test: 15/15 PASS strictly at /Volumes/RAMDisk with 0 collisions and 0 kernel leaks.
• Master E2E suite (run_e2e_tests.sh): 3 consecutive runs passed 192/192 tests across all 5 tiers (total 576/576 tests passed, exit code 0 on all runs).
• Residual state: mount | grep -i ramdisk (exit 1) and hdiutil info | grep -i ram:// (exit 1) confirmed 0 mounts and 0 residual devices.
• Git remotes: git push fleet main && git push backup main && git push origin main succeeded with 0 dirty and 0 0 ahead-behind.