simplify: delegate osroot.MkdirAll to native os.Root.MkdirAll

0e4b26f→main·

Soph·1mo ago·3 files·+10 added/-44 removed

Go 1.26's os.Root has a native MkdirAll, so the hand-rolled per-segment Mkdir loop (with its ToSlash/Trim/path.Join handling and extra imports) collapses to a one-line delegation — battle-tested and stats before creating. Also:

• drop the dead dir != "" guard in the rewind restore loop (path.Dir never returns "")
• drop TestMkdirAll_EmptyOrDotIsNoop, which exercised the removed Trim/no-op logic; the call site never passes ""/"."
• correct the now-stale osroot package doc that listed MkdirAll as unsupported

Pure cleanup from a /simplify review; no behavior change.

Co-Authored-By: Claude Opus 4.8 (1M context) noreply@anthropic.com

Sessions

Changes

3

• cmd/entire/cli

• osroot

  • Mosroot.go+9/-31

  • Mosroot_test.go-12

  • strategy

    • Mmanual_commit_rewind.go+1/-1

// (Go 1.24+). These helpers ensure that file operations cannot escape a scoped
// directory, preventing symlink attacks and TOCTOU races at the kernel level.
//
// os.Root supports: Open, OpenFile, Create, Stat, Lstat, Mkdir, Remove, OpenRoot.
// os.Root does NOT support: MkdirAll, WriteFile, ReadFile, Rename, RemoveAll.
// For unsupported operations, callers should use standard os functions with
// lexical validation.
// These wrappers predate Go 1.25, which added native ReadFile/WriteFile/MkdirAll
// (etc.) on *os.Root; they remain as the codebase's stable, consistent helper
// surface and delegate to the native methods where those now exist.
//
// Errors from these functions are returned unwrapped so that callers can use
// os.IsNotExist() and errors.Is() directly without losing the original sentinel.
package osroot

import (
    "errors"
    "io"
    "io/fs"
    "os"
    "path"
    "path/filepath"
    "strings"
)

// ReadFile reads the named file relative to root using os.Root for
// MkdirAll creates the directory named by name, along with any necessary
// parents, relative to root. Each level is created with os.Root.Mkdir so the
// kernel enforces containment: unlike os.MkdirAll, it cannot create directories
// outside root. A name that escapes root (absolute, or containing ".." segments
// that climb above root) is rejected by os.Root and returns an error. Already-
// existing directories are tolerated. name may use either OS-native or forward
// slashes; an empty or "." name is a no-op.
func MkdirAll(root *os.Root, name string, perm os.FileMode) error {
    name = strings.Trim(filepath.ToSlash(name), "/")
    if name == "" || name == "." {
        return nil
    }

cur := ""
    for _, part := range strings.Split(name, "/") {
        if part == "" {
            continue
        }
        cur = path.Join(cur, part)
        if err := root.Mkdir(cur, perm); err != nil && !errors.Is(err, fs.ErrExist) {
            return err //nolint:wrapcheck // preserve original error (incl. traversal rejection) for callers
        }
    }
    return nil
}

// Remove removes the named file relative to root using os.Root for