Faithful port of the GOLD versioned engine (no reinvention). Replaces the mtime
full-copy-into-per-run-dirs remnant with ONE persistent store
(.backup_system/versioned/) using GOLD's file-folder packaging:
<parent>/<name>/<name> current (copy2, mtime preserved)
<parent>/<name>/<stem>-baseline-<date>.<ext> first-run full copy, never touched
<parent>/<name>/<name>_diffs/<name>_v<old-mtime>.diff unified-diff per change
Patrick's laws, all enforced + tested:
- versioned backs up the EXACT same files as snapshot (same scan/ignore;
all.py shares one scan between modes)
- first versioned run = baseline snapshot of that state
- append-only: versioned NEVER deletes (cleanup stays snapshot-only)
- change detection is LEDGER-FREE (source mtime vs store-current mtime) —
removes versioned's use of shared timestamps.json, killing the
snapshot-starves-versioned regression
New diff/restore.py (list_versions + restore_file); diff/generator.py wired
(binary detection, DIFF include/ignore patterns); path/builder.py file-folder
versioned branch (root/ wrap, >50-char hash shortening). +15 tests -> 125.
Verified by artifact (audit 100% all 36, pytest 125, ruff clean) + LIVE
end-to-end: snapshot-first-then-versioned baselines all 5 files (starvation
dead) -> edit -> diff with old-mtime timestamp + current overwritten + baseline
intact -> source delete -> versioned store untouched while snapshot
mirror-deletes -> restore round-trip byte-identical.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
