message: add more style matching examples
diff: @@ -20,9 +20,22 @@ xdescribe('SomeComponent', () => {
  // this is generally how you test that a prop renders one or more styles
  it('renders "x" prop into styles', () => {
  + // use the .toMatchKeys() to test a subset of the rendered styles
  expect(renderStyles(<SomeComponent scheme="green" />)).toMatchKeys({
  'background-color': theme.colors.green[5]
  })
  +
  + // or use .toEqual() if:
  + // * your component shouldn't render any other styles; or
  + // * you know the other ("base") styles that your component should
  + // render, and you can spread them into the result
  + const defaultStyles = {
  + color: theme.colors.bodytext
  + }
  + expect(renderStyles(<SomeComponent scheme="green" />)).toEqual({
  + ...defaultStyles,
  + 'background-color': theme.colors.green[5]
  + })
  })
  })
  