Feature: Sandbox filesystem utilities
  Tests for the shared _fs_utils module used by CopyOnWriteSandbox and
  OverlaySandbox for pre-commit backup and atomic rollback.

  # backup_directory

  Scenario: backup_directory copies files preserving permissions and timestamps
    Given a source directory with files having varied permissions
    And an empty destination directory
    When I call backup_directory from source to destination
    Then the destination should contain all source files
    And file permissions should match between source and destination
    And file timestamps should match between source and destination

  Scenario: backup_directory preserves symlinks
    Given a source directory with a symlink
    And an empty destination directory
    When I call backup_directory from source to destination
    Then the destination should contain a symlink with the same target

  Scenario: backup_directory preserves root directory permissions
    Given a source directory with restricted permissions
    And an empty destination directory
    When I call backup_directory from source to destination
    Then the destination root permissions should match the source root permissions

  Scenario: backup_directory preserves directory timestamps
    Given a source directory with files having varied permissions
    And an empty destination directory
    When I call backup_directory from source to destination
    Then directory timestamps should match between source and destination

  # safe_restore

  Scenario: safe_restore atomically restores from backup
    Given an original directory with known content
    And a backup directory with different content
    When I call safe_restore from backup to original
    Then the original should contain the backup content
    And the backup directory should have been removed

  Scenario: safe_restore preserves original on rename failure
    Given an original directory with known content
    And a backup path that will cause rename to fail
    When I call safe_restore expecting an error
    Then the original directory should still contain its original content

  Scenario: safe_restore cleans up temporary rollback directory on success
    Given an original directory with known content
    And a backup directory with different content
    When I call safe_restore from backup to original
    Then the original should contain the backup content
    And no atomic-rollback-old directories should remain in the parent