## Summary
- on macOS, resolve the curated plugin sync Git executable without
executing it
- treat Apple’s `/usr/bin/git` shim as unavailable when `xcode-select
-p` reports that developer tools are absent
- skip directly to the existing GitHub HTTP fallback in that case
- preserve the original `git` command lookup on Windows and Linux,
including CCA
## Root cause
Curated plugin startup sync invokes `git ls-remote` before its HTTP
fallback. On a clean Mac, `git` resolves to Apple’s `/usr/bin/git` shim,
and executing the shim opens the Xcode Command Line Tools installer
before the process can fail and reach HTTP.
On macOS, this change resolves Git through `PATH` without executing it.
If the selected binary is Apple’s shim and developer tools are
unavailable, startup sync marks the Git transport unavailable and enters
the existing HTTP fallback immediately.
The new availability detection is macOS-only by construction. Windows
and Linux still execute the literal `git` command as before. If Git is
missing on Windows, the existing spawn-error path falls back to HTTP;
Linux/CCA receives no new lookup or startup behavior.
## Eager Git audit
I also audited production Git process spawns in `codex-rs`.
- This curated catalog sync is the only default projectless app-server
startup path found.
- Configured Git marketplace auto-upgrade runs Git at plugin startup,
but only after a user has explicitly configured a Git marketplace.
- Experimental Memories has background Git metadata/baseline paths when
the feature is enabled.
- The separate cloud-tasks UI probes Git during environment
autodetection.
- Normal thread/turn Git metadata is gated by filesystem discovery of an
existing `.git` entry.
- Marketplace add/install, patch apply, doctor, and TUI `/diff` paths
are explicitly user-invoked.
## Validation
- `just fmt`
- `just bazel-lock-update` — succeeded with no lockfile delta
- `just test -p codex-core-plugins` — 313 passed
- `just fix -p codex-core-plugins` — completed; emitted one pre-existing
unrelated `large_enum_variant` warning in `manifest.rs`
- `git diff --check`
## Why
Several users have reported data loss from this bug, including tracked
files being deleted or replaced and branches appearing to be reset to
the curated plugins repository. This can happen during startup, before
the model chooses to edit anything.
Ambient repository variables such as `GIT_DIR` and `GIT_WORK_TREE` can
override the repository selected by `git -C`, redirecting startup sync's
`git reset --hard` and `git clean -fdx` into the user's active
workspace.
## What
Route every startup-sync Git invocation through a shared command builder
that removes repository-local environment variables before execution.
Add regression coverage to keep those variables isolated.
Fixes#27416
# Summary
Reduce download traffic to `github.com/openai/plugins` while continuing
to check for updates on every Codex startup.
# Root cause
The startup sync replaced the local repository with a fresh shallow
clone whenever the remote revision changed. At Codex's global scale,
repeatedly downloading the repository created excessive GitHub traffic.
# Changes
- Run `git ls-remote` on each startup to read the remote HEAD SHA.
- Skip all repository downloads when the local and remote SHAs match.
- Update existing checkouts with an exact-SHA shallow `git fetch`,
followed by reset and clean.
- Bootstrap new installations with `git init` plus the same shallow
fetch, rather than cloning.
- Keep the existing file lock so concurrent Codex processes serialize
updates and do not duplicate fetches.
- Preserve the existing GitHub HTTP and export archive fallback
behavior.
# Impact
Each startup makes one lightweight remote HEAD check. Repository objects
are downloaded only when the revision changes, and existing Git objects
are reused during updates.
# Validation
- `just test -p codex-core-plugins startup_sync` (15 tests passed)
- `just test -p codex-core-plugins` (201 tests passed)
- `just clippy -p codex-core-plugins` (passes with one pre-existing
`large_enum_variant` warning)
- Production app-server smoke test against GitHub:
- Fresh home: `ls-remote`, `git init`, one exact-SHA shallow fetch
- Unchanged restart: `ls-remote` and local `rev-parse` only; no fetch or
clone
- Bench smoke passed
Francis Chalissery