enzyme find can't find the child element under a dom

Question

I am using karma, enzyme, chai as test framework for a react project. Below is the code I used in my test case. I used redux-mock to mock the store state.

const initialState = {
}
const store = mockStore(initialState)
describe('test suite', () => {
  it('testcase1', () => {
    const wrapper = mount(
      <Provider store={store}>
        <div>
        </div>
      </Provider>
    )
    expect(wrapper.find(<div>)).to.have.length(1)
  })
})

When I run this test case, I got below error:

AssertionError: expected { Object (component, root, ...) } to have a length of 1 but got 0

It seems that enzyme can't find the 'div' element. Did I miss anything here? How can I let the enzyme work?