Read global git config behind symlinked dirs

[Soph]

https://entire.io/gh/entireio/cli/trails/434

Problem

A customer reported a flood of warnings during checkpoint push:

[entire] Syncing entire/checkpoints/v1 with remote......
warning: failed to load global git config: path escapes from parent: "Users/jag/.config/git/config"
warning: failed to load global git config: path escapes from parent: "Users/jag/.config/git/config"
... (repeated per cherry-picked commit)

Root cause

The customer has ~/.config (or another intermediate path component) as an absolute symlink — standard behavior for dotfile managers (chezmoi, GNU Stow, yadm, …). With no ~/.gitconfig, go-git falls back to the XDG path ~/.config/git/config.

go-git's default config loader (xconfig.NewAuto on osfs.Default) reads config files through Go's os.Root, which rejects an absolute symlink in any path component — even one that resolves back inside the root — returning path escapes from parent. Plain os.Open/os.ReadFile follow the symlink fine; only os.Root chokes. (Reproduced verbatim, missing leading slash and all.)

This wasn't just noise. The global config was silently dropped, so:

1. Author identity fell back to Unknown/unknown@local for checkpoint commits (GetGitAuthorFromRepo → repo.ConfigScoped).
2. Commit signing was skipped (commit.gpgsign never read).
3. The warning printed once per commit during the push/rebase loop — the flood.

Fix

cmd/entire/cli/checkpoint/configloader.go registers a ConfigLoader plugin backed by osSymlinkFS, a minimal billy.Basic using plain os calls so config reads follow symlinks the way git itself does. plugin.Register replaces go-git's default factory during package init (before any plugin.Get).

The adapter returns raw os errors unwrapped because go-git's auto loader uses os.IsNotExist(err) (the legacy non-unwrapping check) to fall through absent config files — wrapping would break that. Hence the per-file wrapcheck exclusion, with the reason documented in .golangci.yaml.

Tests

• TestOSSymlinkFS_ReadsGlobalConfigBehindSymlink — reproduces the exact path escapes from parent failure with the default loader and confirms osSymlinkFS reads through the symlink.
• TestGetGitAuthorFromRepo_GlobalConfigBehindSymlink — end-to-end: author identity now resolves from a global config behind a symlinked ~/.config instead of falling back to Unknown. (Verified it fails with name = "Unknown" when reverted to the default loader.)

Full suite green (5210 tests), lint clean.

Upstream

This is fundamentally a go-git/go-billy limitation (the auto loader reading trusted host config through os.Root, diverging from git's symlink-following behavior). A separate upstream conversation/PR will pursue the durable fix; this workaround is forward-compatible and can be dropped once upstream lands.

Draft notes / open questions

• Left the deprecated config.LoadConfig(GlobalScope) fallback at committed.go:1913 (still uses osfs.Default) untouched, since it's only reached when ConfigScoped returns empty — which the fix now prevents. Could harden it too.
• The init()-based registry override is slightly implicit; open to moving it to an explicit call in root setup if preferred.

🤖 Generated with Claude Code

---

Note

Low Risk
Localized checkpoint package init and filesystem adapter for config reads; behavior change only affects environments where global config was previously unreadable.

Overview
Fixes global git config not loading when ~/.config (or similar) is an absolute symlink—common with dotfile managers. go-git’s default loader used os.Root and failed with path escapes from parent, so repo.ConfigScoped dropped global settings: checkpoint commits used Unknown author, GPG signing was skipped, and push/sync logged the same warning once per cherry-picked commit.

Adds configloader.go: at package init, registers a go-git ConfigLoader backed by osSymlinkFS (billy.Basic over plain os.Open/os.Stat) so config paths follow symlinks like git. GetGitAuthorFromRepo comments point at this loader. Lint: allow billy.File in ireturn, wrapcheck off for configloader.go (raw os errors required for os.IsNotExist fall-through). Tests reproduce the default-loader failure and assert author resolution end-to-end (non-Windows).

^{Reviewed by Cursor Bugbot for commit 4b31870. Configure here.}

[Copilot]

Pull request overview

This PR fixes go-git failing to read global git config when $HOME/.config (or another path component) is an absolute symlink, which previously caused global config to be dropped (e.g., author identity/signing) and produced repeated warnings during checkpoint operations.

Changes:

• Registers a custom go-git ConfigLoader (via a symlink-following osSymlinkFS) to load global/system config using plain os calls.
• Adds tests that reproduce the os.Root “path escapes from parent” failure and validate the fix end-to-end via GetGitAuthorFromRepo.
• Updates lint config/docs to support the new adapter and document the behavior.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
cmd/entire/cli/checkpoint/configloader.go	Adds symlink-following ConfigLoader override via osSymlinkFS.
cmd/entire/cli/checkpoint/configloader_test.go	Repro + end-to-end tests for symlinked global config behavior.
cmd/entire/cli/checkpoint/committed.go	Updates comments to reference the new config loader behavior.
CLAUDE.md	Documents the new configloader.go component and rationale.
.golangci.yaml	Adjusts lint allowances/exclusions to accommodate the new adapter.