Question: How do I check if a component is not present, i.e. that a specific component has not been rendered?

Answer: 
If you're using [react-testing-library](https://testing-library.com/docs/dom-testing-library/api-queries#queryby) (I know the OP wasn't but I found this question via web search) then this will work:

```
expect(component.queryByText("Text I care about")).not.toBeInTheDocument();

```

You can query by `Text`, `Role`, and several others. See [docs](https://testing-library.com/docs/dom-testing-library/api-queries#queryby) for more info.

**Note:** `queryBy*` will return `null` if it is not found. If you use `getBy*` then it will error out for elements not found.
`.contains` does not expect a selector, unlike find. You can look at the length attribute of the ShallowWrapper

`expect(wrapper.find('...')).toHaveLength(0)`

I found I needed to use this syntax with Enzyme and Jest to test if a Connected Component existed in the rendered output.