e2d0a46608
Replace unreliable filesystem ctime/mtime with git log timestamps. A single batch `git log` walks the full commit history to extract created_at (oldest commit) and modified_at (newest commit) for each .md file. Falls back to filesystem dates for non-git vaults and uncommitted files. Cache version bumped to 10 for full rescan. ADR 0039 documents the decision. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
2.3 KiB
2.3 KiB
type, id, title, status, date
| type | id | title | status | date |
|---|---|---|---|---|
| ADR | 0039 | Use git history for note creation and modification dates | active | 2026-04-02 |
Context
Filesystem metadata (ctime/mtime) is unreliable for a git-backed vault. After git clone, git pull, or iCloud sync, files appear "newly created" even when they have years of history. This causes incorrect sort ordering in the note list and wrong dates in the inspector panel.
Decision
Use git log to determine the true creation and modification dates for notes. A single batch git log --format="COMMIT %aI" --name-only command walks the full commit history and extracts:
- modified_at = author date of the most recent commit that touched the file
- created_at = author date of the oldest commit that touched the file
The batch approach runs once per vault scan (not per-file), parsing the log output in a single linear pass. Results are stored in a HashMap<String, GitDates> keyed by vault-relative path and threaded through the existing parse_md_file / scan_vault / scan_vault_cached pipeline.
Fallback to filesystem dates
- Non-git vaults (no
.gitdirectory): all notes use filesystemmtime/ctime. - Uncommitted new files: not in git log output, so filesystem dates are used automatically.
- Single-file reloads (
reload_entry): use filesystem dates since the file was just saved and the most accurate timestamp is the filesystem one.
Options considered
- Per-file
git log: Correct but O(n) subprocesses. Too slow for vaults with 500+ notes. - Frontmatter dates (e.g.,
created: 2025-01-15): Requires user discipline. Not automatic. Breaks when users forget to set them. - Filesystem metadata (current): Unreliable across clones, pulls, and cloud sync.
- Single batch
git log(chosen): One subprocess, O(n) parsing, correct dates for all committed files.
Consequences
- Note sort-by-created and sort-by-modified now reflect true git history, stable across clones and machines.
- First vault scan runs one
git logover the full history. For a vault with 1000 files and 500 commits, output is ~100KB and parses in <100ms. - Renamed files get
created_atset to the rename commit date (not the original creation). Acceptable trade-off vs. the complexity of rename tracking. CACHE_VERSIONbumped from 9 to 10 to force a full rescan with git dates on upgrade.