revert.py
python
sha256:51ce277f663e01a43eaffbe77509b1de7ac2d4251b55d23306304bcdeb92c90d
feat(pack): delta-encode snapshots in MPackBundle wire format
Sonnet 4.6
minor
⚠ breaking
121 days ago
| 1 | """``muse revert`` — create a new commit that undoes a prior commit. |
| 2 | |
| 3 | Revert is the safe undo: instead of rewriting history (as ``muse reset`` |
| 4 | does), revert appends a new commit whose snapshot matches the target |
| 5 | commit's parent snapshot. The branch history stays linear and auditable. |
| 6 | |
| 7 | Usage:: |
| 8 | |
| 9 | muse revert <ref> — revert and commit immediately |
| 10 | muse revert <ref> --no-commit — apply the revert to the working tree and |
| 11 | stage changes for the next commit |
| 12 | muse revert <ref> --dry-run — simulate without writing anything |
| 13 | |
| 14 | Ref formats accepted:: |
| 15 | |
| 16 | HEAD — most recent commit on the current branch |
| 17 | HEAD~1 — one commit before HEAD (if supported by resolve_commit_ref) |
| 18 | sha256:… — full content-addressed commit ID |
| 19 | <hex-prefix> — unambiguous prefix (min 7 chars) of a commit ID |
| 20 | |
| 21 | JSON output (``--format json`` or ``--json``):: |
| 22 | |
| 23 | { |
| 24 | "status": "reverted" | "applied", |
| 25 | "commit_id": "<sha256>" | null, |
| 26 | "branch": "<current-branch>", |
| 27 | "ref": "<ref-as-passed>", |
| 28 | "reverted_commit_id": "<sha256>", |
| 29 | "snapshot_id": "<sha256>", |
| 30 | "message": "<revert-commit-message>", |
| 31 | "no_commit": false, |
| 32 | "dry_run": false, |
| 33 | "files_added": ["path/restored.py", ...], |
| 34 | "files_modified": ["path/changed.py", ...], |
| 35 | "files_removed": ["path/deleted.py", ...], |
| 36 | "duration_ms": 12.3, |
| 37 | "exit_code": 0 |
| 38 | } |
| 39 | |
| 40 | The schema is **identical** for all paths (normal, ``--no-commit``, |
| 41 | ``--dry-run``); only ``status``, ``commit_id``, ``no_commit``, ``dry_run``, |
| 42 | and the file-diff lists vary. ``duration_ms`` and ``exit_code`` are always |
| 43 | present — including on error responses — so agents can parse the outcome |
| 44 | without inspecting the shell exit status. |
| 45 | |
| 46 | File-diff fields |
| 47 | ---------------- |
| 48 | ``files_added`` — paths present in the parent snapshot but absent from the |
| 49 | current HEAD snapshot; these files will be restored on disk. |
| 50 | ``files_modified`` — paths in both snapshots but with different object IDs; |
| 51 | these files will be overwritten with the older content. |
| 52 | ``files_removed`` — paths in the current HEAD snapshot but absent from the |
| 53 | parent snapshot; these files will be deleted from disk. |
| 54 | |
| 55 | Agent recipe:: |
| 56 | |
| 57 | result = muse revert HEAD --json |
| 58 | if result["exit_code"] != 0: |
| 59 | handle_error(result) |
| 60 | log(f"reverted {result['reverted_commit_id'][:20]} in {result['duration_ms']:.1f}ms") |
| 61 | log(f"+{len(result['files_added'])} -{len(result['files_removed'])} ~{len(result['files_modified'])}") |
| 62 | |
| 63 | Exit codes:: |
| 64 | |
| 65 | 0 — success (reverted, applied to workdir, or dry-run) |
| 66 | 1 — ref not found, root commit, invalid format |
| 67 | 2 — not a Muse repository |
| 68 | 3 — internal error (parent commit or snapshot missing) |
| 69 | """ |
| 70 | |
| 71 | import argparse |
| 72 | import datetime |
| 73 | import json |
| 74 | import logging |
| 75 | import pathlib |
| 76 | import sys |
| 77 | from muse.core.types import short_id |
| 78 | from muse.core.envelope import EnvelopeJson, make_envelope |
| 79 | from muse.core.errors import ExitCode |
| 80 | from muse.core.reflog import append_reflog |
| 81 | from muse.core.repo import read_repo_id, require_repo |
| 82 | from muse.cli.config import get_config_value |
| 83 | from muse.core.validation import sanitize_provenance |
| 84 | from muse.core.snapshot import compute_commit_id |
| 85 | from muse.core.store import ( |
| 86 | CommitRecord, |
| 87 | Manifest, |
| 88 | RefConflictError, |
| 89 | get_head_commit_id, |
| 90 | read_commit, |
| 91 | read_current_branch, |
| 92 | read_snapshot, |
| 93 | resolve_commit_ref, |
| 94 | write_branch_ref, |
| 95 | write_commit, |
| 96 | ) |
| 97 | from muse.core.validation import sanitize_display, validate_branch_name |
| 98 | from muse.core.workdir import apply_manifest |
| 99 | from muse.core.timing import start_timer |
| 100 | from muse.cli.guard import require_clean_workdir |
| 101 | from muse.plugins.code.stage import StagedFileMap, make_entry, read_stage, write_stage |
| 102 | |
| 103 | logger = logging.getLogger(__name__) |
| 104 | |
| 105 | # --------------------------------------------------------------------------- |
| 106 | # JSON wire format |
| 107 | # --------------------------------------------------------------------------- |
| 108 | |
| 109 | class _RevertJson(EnvelopeJson, total=False): |
| 110 | """JSON output schema — identical across all paths including errors.""" |
| 111 | |
| 112 | status: str # "reverted" | "applied" | "error" |
| 113 | commit_id: str | None # null on --no-commit / --dry-run / error |
| 114 | branch: str |
| 115 | ref: str |
| 116 | reverted_commit_id: str | None |
| 117 | snapshot_id: str | None |
| 118 | message: str |
| 119 | no_commit: bool |
| 120 | dry_run: bool |
| 121 | files_added: list[str] # restored from parent snapshot |
| 122 | files_modified: list[str] # content changed relative to current HEAD |
| 123 | files_removed: list[str] # deleted to match parent snapshot |
| 124 | |
| 125 | # --------------------------------------------------------------------------- |
| 126 | # Helpers |
| 127 | # --------------------------------------------------------------------------- |
| 128 | |
| 129 | def _compute_diff( |
| 130 | current_manifest: Manifest, |
| 131 | target_manifest: Manifest, |
| 132 | ) -> tuple[list[str], list[str], list[str]]: |
| 133 | """Return (files_added, files_modified, files_removed) for the revert. |
| 134 | |
| 135 | The *revert* moves the working tree FROM *current_manifest* TO |
| 136 | *target_manifest* (the parent snapshot). |
| 137 | |
| 138 | - ``files_added`` — in target but not in current (will be restored) |
| 139 | - ``files_modified`` — in both but different object IDs (will be overwritten) |
| 140 | - ``files_removed`` — in current but not in target (will be deleted) |
| 141 | """ |
| 142 | current_keys = set(current_manifest) |
| 143 | target_keys = set(target_manifest) |
| 144 | |
| 145 | files_added = sorted(target_keys - current_keys) |
| 146 | files_removed = sorted(current_keys - target_keys) |
| 147 | files_modified = sorted( |
| 148 | p for p in current_keys & target_keys |
| 149 | if current_manifest[p] != target_manifest[p] |
| 150 | ) |
| 151 | return files_added, files_modified, files_removed |
| 152 | |
| 153 | def _apply_manifest_safe( |
| 154 | root: pathlib.Path, |
| 155 | prev_manifest: Manifest, |
| 156 | target_manifest: Manifest, |
| 157 | ) -> None: |
| 158 | """Apply *target_manifest* to the working tree, handling the empty-target case. |
| 159 | |
| 160 | ``apply_manifest`` guards against accidentally applying an empty manifest |
| 161 | when there are previously tracked files. In the revert context an empty |
| 162 | target is always intentional — the caller validated that we're reverting to |
| 163 | a known parent snapshot. We handle the empty case by removing all files |
| 164 | that were in *prev_manifest*. |
| 165 | """ |
| 166 | if not target_manifest: |
| 167 | from muse.core.validation import contain_path |
| 168 | for rel_posix in prev_manifest: |
| 169 | fp = root / rel_posix |
| 170 | if fp.exists(): |
| 171 | fp.unlink() |
| 172 | else: |
| 173 | apply_manifest(root, prev_manifest, target_manifest) |
| 174 | |
| 175 | def _stage_revert( |
| 176 | root: pathlib.Path, |
| 177 | current_manifest: Manifest, |
| 178 | target_manifest: Manifest, |
| 179 | files_added: list[str], |
| 180 | files_modified: list[str], |
| 181 | files_removed: list[str], |
| 182 | ) -> None: |
| 183 | """Update the stage index to reflect the reverted state. |
| 184 | |
| 185 | Called by the ``--no-commit`` path so that ``muse status`` shows staged |
| 186 | changes and ``muse commit`` can record them without a separate |
| 187 | ``muse code add`` step. |
| 188 | |
| 189 | - Paths in *files_removed* → staged as ``D`` (deleted). |
| 190 | - Paths in *files_added* → staged as ``A`` (added, with the target object ID). |
| 191 | - Paths in *files_modified* → staged as ``M`` (modified, with the target object ID). |
| 192 | """ |
| 193 | stage: StagedFileMap = dict(read_stage(root)) |
| 194 | for path in files_removed: |
| 195 | if path in current_manifest: |
| 196 | # Was in HEAD → mark as deleted. |
| 197 | stage[path] = make_entry(object_id="", mode="D") |
| 198 | else: |
| 199 | stage.pop(path, None) |
| 200 | for path in files_added: |
| 201 | stage[path] = make_entry(object_id=target_manifest[path], mode="A") |
| 202 | for path in files_modified: |
| 203 | stage[path] = make_entry(object_id=target_manifest[path], mode="M") |
| 204 | write_stage(root, stage) |
| 205 | |
| 206 | # --------------------------------------------------------------------------- |
| 207 | # Command registration |
| 208 | # --------------------------------------------------------------------------- |
| 209 | |
| 210 | def register(subparsers: "argparse._SubParsersAction[argparse.ArgumentParser]") -> None: |
| 211 | """Register the ``muse revert`` subcommand and all its flags.""" |
| 212 | parser = subparsers.add_parser( |
| 213 | "revert", |
| 214 | help="Create a new commit that undoes a prior commit.", |
| 215 | description=__doc__, |
| 216 | formatter_class=argparse.RawDescriptionHelpFormatter, |
| 217 | ) |
| 218 | parser.add_argument("ref", help="Commit to revert (ID, HEAD, HEAD~N).") |
| 219 | parser.add_argument( |
| 220 | "-m", "--message", default=None, |
| 221 | help="Override the revert commit message.", |
| 222 | ) |
| 223 | parser.add_argument( |
| 224 | "--no-commit", action="store_true", dest="no_commit", |
| 225 | help=( |
| 226 | "Apply the revert to the working tree and stage the changes " |
| 227 | "without creating a commit. Run 'muse commit' afterwards." |
| 228 | ), |
| 229 | ) |
| 230 | parser.add_argument( |
| 231 | "--force", action="store_true", |
| 232 | help="Proceed even if the working tree has uncommitted changes.", |
| 233 | ) |
| 234 | parser.add_argument( |
| 235 | "--dry-run", "-n", action="store_true", dest="dry_run", |
| 236 | help=( |
| 237 | "Simulate the revert without writing anything. " |
| 238 | "Validates the target ref and its parent snapshot." |
| 239 | ), |
| 240 | ) |
| 241 | parser.add_argument( |
| 242 | "--json", "-j", action="store_true", dest="json_out", |
| 243 | help="Emit machine-readable JSON instead of human text.", |
| 244 | ) |
| 245 | parser.set_defaults(func=run) |
| 246 | |
| 247 | # --------------------------------------------------------------------------- |
| 248 | # Main handler |
| 249 | # --------------------------------------------------------------------------- |
| 250 | |
| 251 | def run(args: argparse.Namespace) -> None: |
| 252 | """Create a new commit that undoes a prior commit. |
| 253 | |
| 254 | All error messages are written to **stderr**; stdout is reserved for |
| 255 | structured output only. ``files_added`` / ``files_modified`` / |
| 256 | ``files_removed`` are populated on all three paths (normal, |
| 257 | ``--no-commit``, ``--dry-run``). |
| 258 | |
| 259 | Agent quickstart:: |
| 260 | |
| 261 | muse revert HEAD --json |
| 262 | muse revert HEAD --no-commit --json |
| 263 | muse revert HEAD --dry-run --json |
| 264 | muse revert sha256:abc123 --json |
| 265 | |
| 266 | JSON fields:: |
| 267 | |
| 268 | status str "reverted" | "applied" | "error" |
| 269 | commit_id str|null New revert commit ID; null for --no-commit/--dry-run |
| 270 | branch str Current branch name |
| 271 | ref str Ref as passed by the caller |
| 272 | reverted_commit_id str|null Commit ID that was reverted |
| 273 | snapshot_id str|null Snapshot ID restored by the revert |
| 274 | message str Revert commit message |
| 275 | no_commit bool True when --no-commit was given |
| 276 | dry_run bool True when no writes were made |
| 277 | files_added list[str] Paths restored from the parent snapshot |
| 278 | files_modified list[str] Paths overwritten with older content |
| 279 | files_removed list[str] Paths deleted to match the parent snapshot |
| 280 | |
| 281 | Exit codes:: |
| 282 | |
| 283 | 0 Success (reverted, applied, or dry-run). |
| 284 | 1 Ref not found, root commit, or invalid format. |
| 285 | 2 Not a Muse repository. |
| 286 | 3 Internal error (parent commit or snapshot missing). |
| 287 | """ |
| 288 | elapsed = start_timer() |
| 289 | |
| 290 | ref: str = args.ref |
| 291 | message: str | None = args.message |
| 292 | no_commit: bool = args.no_commit |
| 293 | force: bool = args.force |
| 294 | dry_run: bool = getattr(args, "dry_run", False) |
| 295 | json_out: bool = args.json_out |
| 296 | |
| 297 | def _emit_error(exit_code: int, error_key: str, msg: str, **extra: str) -> None: |
| 298 | """Emit a JSON error envelope on stdout when json_out is True.""" |
| 299 | if json_out: |
| 300 | payload = { |
| 301 | **make_envelope(elapsed, exit_code=exit_code), |
| 302 | "status": "error", |
| 303 | "commit_id": None, |
| 304 | "branch": "", |
| 305 | "ref": ref, |
| 306 | "reverted_commit_id": None, |
| 307 | "snapshot_id": None, |
| 308 | "message": msg, |
| 309 | "no_commit": no_commit, |
| 310 | "dry_run": dry_run, |
| 311 | "files_added": [], |
| 312 | "files_modified": [], |
| 313 | "files_removed": [], |
| 314 | "error": error_key, |
| 315 | **extra, |
| 316 | } |
| 317 | print(json.dumps(payload)) |
| 318 | |
| 319 | root = require_repo() |
| 320 | # Dry-run never touches the working tree. |
| 321 | if not dry_run: |
| 322 | require_clean_workdir(root, "revert", force=force, json_out=json_out) |
| 323 | repo_id = read_repo_id(root) |
| 324 | branch = read_current_branch(root) |
| 325 | |
| 326 | try: |
| 327 | validate_branch_name(branch) |
| 328 | except ValueError as exc: |
| 329 | _emit_error(ExitCode.INTERNAL_ERROR, "invalid_branch", str(exc)) |
| 330 | print( |
| 331 | f"❌ Current branch name is invalid: {sanitize_display(str(exc))}", |
| 332 | file=sys.stderr, |
| 333 | ) |
| 334 | raise SystemExit(ExitCode.INTERNAL_ERROR) |
| 335 | |
| 336 | target = resolve_commit_ref(root, repo_id, branch, ref) |
| 337 | if target is None: |
| 338 | _emit_error( |
| 339 | ExitCode.USER_ERROR, "commit_not_found", |
| 340 | f"commit '{ref}' not found", |
| 341 | branch=branch, |
| 342 | ) |
| 343 | print( |
| 344 | f"❌ Commit '{sanitize_display(ref)}' not found.", |
| 345 | file=sys.stderr, |
| 346 | ) |
| 347 | raise SystemExit(ExitCode.USER_ERROR) |
| 348 | |
| 349 | if target.parent_commit_id is None: |
| 350 | _emit_error( |
| 351 | ExitCode.USER_ERROR, "root_commit", |
| 352 | "cannot revert the root commit (no parent to restore)", |
| 353 | branch=branch, |
| 354 | reverted_commit_id=target.commit_id, |
| 355 | ) |
| 356 | print( |
| 357 | "❌ Cannot revert the root commit (no parent to restore).", |
| 358 | file=sys.stderr, |
| 359 | ) |
| 360 | raise SystemExit(ExitCode.USER_ERROR) |
| 361 | |
| 362 | parent_commit = read_commit(root, target.parent_commit_id) |
| 363 | if parent_commit is None: |
| 364 | _emit_error( |
| 365 | ExitCode.INTERNAL_ERROR, "parent_not_found", |
| 366 | f"parent commit {target.parent_commit_id} not found", |
| 367 | branch=branch, |
| 368 | reverted_commit_id=target.commit_id, |
| 369 | ) |
| 370 | print( |
| 371 | f"❌ Parent commit {target.parent_commit_id} not found.", |
| 372 | file=sys.stderr, |
| 373 | ) |
| 374 | raise SystemExit(ExitCode.INTERNAL_ERROR) |
| 375 | |
| 376 | target_snapshot = read_snapshot(root, parent_commit.snapshot_id) |
| 377 | if target_snapshot is None: |
| 378 | _emit_error( |
| 379 | ExitCode.INTERNAL_ERROR, "snapshot_missing", |
| 380 | f"snapshot {parent_commit.snapshot_id} not found", |
| 381 | branch=branch, |
| 382 | reverted_commit_id=target.commit_id, |
| 383 | ) |
| 384 | print( |
| 385 | f"❌ Snapshot {parent_commit.snapshot_id} not found.", |
| 386 | file=sys.stderr, |
| 387 | ) |
| 388 | raise SystemExit(ExitCode.INTERNAL_ERROR) |
| 389 | |
| 390 | # Read the current HEAD snapshot to compute the file-level diff. |
| 391 | head_commit_id = get_head_commit_id(root, branch) |
| 392 | current_manifest: Manifest = {} |
| 393 | if head_commit_id: |
| 394 | head_commit = read_commit(root, head_commit_id) |
| 395 | if head_commit: |
| 396 | head_snap = read_snapshot(root, head_commit.snapshot_id) |
| 397 | if head_snap: |
| 398 | current_manifest = dict(head_snap.manifest) |
| 399 | |
| 400 | # Compute the file-level diff: current → parent (target of revert). |
| 401 | files_added, files_modified, files_removed = _compute_diff( |
| 402 | current_manifest, dict(target_snapshot.manifest) |
| 403 | ) |
| 404 | |
| 405 | # Sanitize the original commit message before embedding it in the revert |
| 406 | # commit message, which is stored permanently on disk. |
| 407 | safe_original_message = sanitize_display(target.message.splitlines()[0]) |
| 408 | revert_message = message or f'Revert "{safe_original_message}"' |
| 409 | |
| 410 | # The parent snapshot is already content-addressed in the object store — |
| 411 | # reuse its snapshot_id directly rather than re-scanning the workdir. |
| 412 | snapshot_id = parent_commit.snapshot_id |
| 413 | |
| 414 | # Dry-run: validate succeeded — report what would happen and exit. |
| 415 | if dry_run: |
| 416 | if json_out: |
| 417 | print(json.dumps(_RevertJson( |
| 418 | **make_envelope(elapsed), |
| 419 | status="reverted", |
| 420 | commit_id=None, |
| 421 | branch=branch, |
| 422 | ref=ref, |
| 423 | reverted_commit_id=target.commit_id, |
| 424 | snapshot_id=snapshot_id, |
| 425 | message=revert_message, |
| 426 | no_commit=no_commit, |
| 427 | dry_run=True, |
| 428 | files_added=files_added, |
| 429 | files_modified=files_modified, |
| 430 | files_removed=files_removed, |
| 431 | ))) |
| 432 | else: |
| 433 | print( |
| 434 | f"[dry-run] Would revert '{sanitize_display(ref)}' " |
| 435 | f"({target.commit_id}) on '{sanitize_display(branch)}'" |
| 436 | ) |
| 437 | return |
| 438 | |
| 439 | if no_commit: |
| 440 | _apply_manifest_safe(root, current_manifest, dict(target_snapshot.manifest)) |
| 441 | _stage_revert( |
| 442 | root, current_manifest, dict(target_snapshot.manifest), |
| 443 | files_added, files_modified, files_removed, |
| 444 | ) |
| 445 | if json_out: |
| 446 | print(json.dumps(_RevertJson( |
| 447 | **make_envelope(elapsed), |
| 448 | status="applied", |
| 449 | commit_id=None, |
| 450 | branch=branch, |
| 451 | ref=ref, |
| 452 | reverted_commit_id=target.commit_id, |
| 453 | snapshot_id=snapshot_id, |
| 454 | message=revert_message, |
| 455 | no_commit=True, |
| 456 | dry_run=False, |
| 457 | files_added=files_added, |
| 458 | files_modified=files_modified, |
| 459 | files_removed=files_removed, |
| 460 | ))) |
| 461 | else: |
| 462 | print( |
| 463 | f"Revert of {target.commit_id} applied to working tree. " |
| 464 | f"Run 'muse commit' to record." |
| 465 | ) |
| 466 | return |
| 467 | |
| 468 | # Correct write ordering for atomicity: |
| 469 | # 1. Compute commit record (all data validated above — no I/O failures possible here). |
| 470 | # 2. write_commit (idempotent — crash here leaves the workdir unchanged). |
| 471 | # 3. apply_manifest (workdir is modified only after the commit is durably stored). |
| 472 | # 4. write_branch_ref (branch pointer advances last — visible to others only when complete). |
| 473 | # 5. append_reflog (non-critical audit trail — never blocks success). |
| 474 | committed_at = datetime.datetime.now(datetime.timezone.utc) |
| 475 | revert_author = sanitize_provenance(get_config_value("user.handle", root) or "") |
| 476 | commit_id = compute_commit_id( |
| 477 | parent_ids=[head_commit_id] if head_commit_id else [], |
| 478 | snapshot_id=snapshot_id, |
| 479 | message=revert_message, |
| 480 | committed_at_iso=committed_at.isoformat(), |
| 481 | author=revert_author, |
| 482 | ) |
| 483 | |
| 484 | write_commit(root, CommitRecord( |
| 485 | commit_id=commit_id, |
| 486 | repo_id=repo_id, |
| 487 | branch=branch, |
| 488 | snapshot_id=snapshot_id, |
| 489 | message=revert_message, |
| 490 | committed_at=committed_at, |
| 491 | parent_commit_id=head_commit_id, |
| 492 | author=revert_author, |
| 493 | )) |
| 494 | _apply_manifest_safe(root, current_manifest, dict(target_snapshot.manifest)) |
| 495 | try: |
| 496 | write_branch_ref(root, branch, commit_id, expected_id=head_commit_id) |
| 497 | except RefConflictError as exc: |
| 498 | print(f"❌ {exc}", file=sys.stderr) |
| 499 | raise SystemExit(ExitCode.USER_ERROR) |
| 500 | append_reflog( |
| 501 | root, branch, old_id=head_commit_id, new_id=commit_id, |
| 502 | author="user", |
| 503 | operation=f"revert: {sanitize_display(ref)} → {commit_id}", |
| 504 | ) |
| 505 | |
| 506 | if json_out: |
| 507 | print(json.dumps(_RevertJson( |
| 508 | **make_envelope(elapsed), |
| 509 | status="reverted", |
| 510 | commit_id=commit_id, |
| 511 | branch=branch, |
| 512 | ref=ref, |
| 513 | reverted_commit_id=target.commit_id, |
| 514 | snapshot_id=snapshot_id, |
| 515 | message=revert_message, |
| 516 | no_commit=False, |
| 517 | dry_run=False, |
| 518 | files_added=files_added, |
| 519 | files_modified=files_modified, |
| 520 | files_removed=files_removed, |
| 521 | ))) |
| 522 | else: |
| 523 | print( |
| 524 | f"[{sanitize_display(branch)} {short_id(commit_id)}] " |
| 525 | f"{sanitize_display(revert_message)}" |
| 526 | ) |
File History
1 commit
sha256:51ce277f663e01a43eaffbe77509b1de7ac2d4251b55d23306304bcdeb92c90d
feat(pack): delta-encode snapshots in MPackBundle wire format
Sonnet 4.6
minor
⚠
121 days ago