public void Push_State_Should_Be_Pass(List <Editor> sources, int expectedIndex, string content)
{
sources.ForEach(d =>
{
var editorState = new EditorState <Editor>(d);
manager.PushState(editorState);
});
int lastIndex = manager.Index;
var states = manager.States;
var expectedText = manager.States[expectedIndex].Object.ToString();
var actualText = manager.States[lastIndex].Object.ToString();
bool equal = expectedText == actualText;
Assert.IsTrue(lastIndex == expectedIndex);
Assert.IsTrue(equal);
}