After bun remove of a vendored package in a bun.lockb project, scan --prune, vendor --revert and remove keep it as "drifted", so vendor --check stays red and its remedy loops #1132

[agent] Found by the scheduled Bun bug-hunt routine (ledger #306).

Summary

In a vendored project that uses a binary bun.lockb, run bun remove <pkg> on a vendored package. No socket-patch command can then clean up its vendored entry:

• vendor --check exits 1 with dependency removed: no lockfile resolves pkg:npm/minimist@1.2.2 any more … run socket-patch scan --mode vendored --prune to revert the vendored entry (the Fix vendor --check unwired cause and remedy (#900) #970 / Decide vendored-entry liveness through one discovery verdict #1050 message).
• scan --mode vendored --prune exits 0 but keeps the entry: GC: kept 1 drifted vendored entry: lock entries were re-resolved since vendoring … undo the drift and re-run vendor --revert to finish (keptVendoredEntries: ["pkg:npm/minimist@1.2.2"]).
• vendor --revert exits 0 with Kept 1 drifted package (vendor_lock_entry_drifted: binary package resolution has drifted).
• remove pkg:npm/minimist@1.2.2 exits 1 with 1 matching entry was drift-kept …; re-run scan --mode vendored to normalize, then remove again. That re-run changes nothing.

The .socket/vendor/npm/<uuid>/ tarball and its ledger entry stay committed, and vendor --check stays red in CI for good. Only hand-deleting the uuid dir and editing .socket/vendor/state.json gets you out.

On a text bun.lock, and on npm's package-lock.json, the same removal is reverted cleanly: prune prints GC: reverted 1 vendored entry and vendor --check goes back to exit 0. So the defect is specific to the binary lockb backend.

Expected (CLI_CONTRACT.md, vendor --revert, lines 803–807)

in the npm family (npm, yarn classic and berry, pnpm, bun) a recorded lock entry that no longer exists at all — the user removed the dependency — is not drift: it warns vendor_lock_entry_removed … so rollback / remove / scan --prune clean up after npm uninstall / yarn remove / pnpm remove / bun remove

The scan --prune paragraph (line 137, leg (b)) also says: "EVERY ledger entry whose dependency is no longer in the lockfile graph is reverted".

Actual

crates/socket-patch-core/src/vendor/bun_binary.rs:520-527 (revert): when the lock contains neither the rewritten snapshot nor the original for the recorded package ID, the record is reported as vendor_lock_entry_drifted ("binary package resolution has drifted"). There's no "entry no longer exists → vendor_lock_entry_removed, nothing to restore" arm like the one the text backend has (bun_lock.rs, the test around line 3600) and npm has (npm_lock.rs ~3350). outcome.drift_skipped() then keeps the artifact, so run_vendor_gc (commands/vendor.rs ~4290) lists it under kept. Meanwhile Discovery::vendor_entry_in_use correctly returns Some(false), which is why vendor --check sends you to --prune.

Repro (Linux, real Bun, local mock of the patch API with a minimist@1.2.2 patch)

# usage: repro.sh <bun-binary>
BUN=$1; D=$(mktemp -d); cd "$D"; git init -q; echo node_modules/ > .gitignore
printf '[install]\nsaveTextLockfile = false\nlinker = "hoisted"\n' > bunfig.toml
echo '{"name":"proj","version":"1.0.0","dependencies":{"minimist":"1.2.2","left-pad":"1.3.0"}}' > package.json
"$BUN" install && git add -A && git commit -qm init
socket-patch scan --mode vendored            # exit 0, both packages vendored into bun.lockb
"$BUN" install --frozen-lockfile && git add -A && git commit -qm vendored
"$BUN" remove minimist && git add -A && git commit -qm "drop minimist"
socket-patch vendor --check; echo $?         # 1: "dependency removed … run scan --mode vendored --prune"
socket-patch scan --mode vendored --prune    # exit 0: "GC: kept 1 drifted vendored entry …"
socket-patch vendor --check; echo $?         # still 1
socket-patch vendor --revert                 # exit 0: "Kept 1 drifted package"
socket-patch remove pkg:npm/minimist@1.2.2; echo $?   # 1: "drift-kept … re-run scan … then remove again"
ls .socket/vendor/npm/                       # 11111111-… (minimist) still there

(left-pad keeps a patched package in the project, so the scan's GC runs. See #1127 for the case where no patched package remains.)

Matrix (main 9472be4, Linux)

It reproduced in two separate runs of each lockb cell. macOS and Windows weren't tested: the backend is platform-independent, and no probe branch was available this run.

Related, but not Bun-specific, so it's being handed to the npm routine rather than filed here: when the dependency is upgraded off the patched version (bun add minimist@1.2.8, npm install minimist@1.2.8), every backend (text bun.lock on 1.1.39–1.4.2, bun.lockb, package-lock.json) gives the same loop. vendor --check says "dependency removed … run --prune", and prune keeps the entry as "drifted".

First bad: not bisected. Release 4.0.0 can't vendor against the local mock. The --prune remedy text came with #970 and the shared in-use verdict with #1050, but the lockb revert arm was already there before them.

Suspect code: crates/socket-patch-core/src/vendor/bun_binary.rs:526.