refactor: cleanup symlink handling

Simplify the `CopyDir` codepath around symlinks; this will help
since afero's MemMapFs still does not support symlinks.

Also remove the comment that was a bald-faced lie.

internal/repository/copy.go

@@ -104,7 +104,7 @@ func (r *Copy) CopyFile(
 
 // CopyDir recursively copies a directory tree, attempting to preserve permissions.
 // Source directory must exist, destination directory must *not* exist.
-// Symlinks are ignored and skipped.
+// Symlinks are implicitly dereferenced.
 func (r *Copy) CopyDir(
  src string,
  dst string,
@@ -149,17 +149,10 @@ func (r *Copy) CopyDir(
  srcPath := filepath.Join(src, entry.Name())
  dstPath := filepath.Join(dst, entry.Name())
 
- // If a symlink, we copy the contents
- if entry.Mode()&os.ModeSymlink != 0 {
- target, err := filepath.EvalSymlinks(srcPath)
- if err != nil {
- return err
- }
-
- entry, err = r.appFs.Stat(target)
- if err != nil {
- return err
- }
+ // Dereference any symlinks and copy their contents instead
+ entry, err = r.appFs.Stat(srcPath)
+ if err != nil {
+ return err
  }
 
  if entry.IsDir() {