You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: active_snapshot_test.rb
    path of file: ./repos/active_snapshot/test/unit
    
    the code of the file until where you have to start completion: require "test_helper"

class ActiveSnapshotTest < ActiveSupport::TestCase

  def test_exposes_main_module
    assert ActiveSnapshot.is_a?(Module)
  end

  def test_exposes_version
    assert ActiveSnapshot::VERSION
  end

  def test_snapshot_lifecycle
    identifier = "snapshot-1"

    klass = Post

    parent = klass.first

    original_parent_updated_at = parent.updated_at

    child = parent.comments.create!(content: :foo)
    original_child_updated_at = child.updated_at

 
    
  def test_snapshot_lifecycle
    identifier = "snapshot-1"

    klass = Post

    parent = klass.first

    original_parent_updated_at = parent.updated_at

    child = parent.comments.create!(content: :foo)
    original_child_updated_at = child.updated_at

    assert_difference ->{ ActiveSnapshot::Snapshot.count }, 1 do
      assert_difference ->{ ActiveSnapshot::SnapshotItem.count }, 2 do
        @snapshot = parent.create_snapshot!(identifier: identifier)
      end
    end

    parent.update_columns(updated_at: 1.day.from_now)

    parent.update_columns(updated_at: 1.day.from_now)

    child.destroy!

    parent.comments.create!(content: :foo)
    parent.comments.create!(content: :bar)

    assert_no_difference ->{ ActiveSnapshot::Snapshot.count } do
      assert_no_difference ->{ ActiveSnapshot::SnapshotItem.count } do
        @snapshot.restore!
      end
    end

    assert_equal 1, ActiveSnapshot::Snapshot.where(identifier: identifier).count

    parent.reload

    assert_equal 1, parent.children_to_snapshot[:comments][:records].count

    ### Test Data Chang
    assert_time_match original_parent_updated_at, parent.updated_at
    assert_time_match original_child_updated_at, parent.children_to_snapshot[:comments][:records].first.updated_at
  end