Set URL params while testing with Jest & Enzyme

It seems like when outside the test, the Search component receives the match props correctly.
You could pass it as props when shallow rendering it in the test:

test("Search should render correct amount of shows", () => {
 const match = { params: { searchTerm: 'foo' } }
 const component = shallow(<Search shows={preload.shows} match={match}/>);
 expect(component.find(ShowCard).length).toEqual(preload.shows.length);
});

And in that case, you're not changing the component under test in a bad way, your test case just found a bug, which is good and should be aimed in tests, and you improved the component by implementing a default props, making it more robust.