import { render } from ".." ; let treeA ; let treeB ; beforeAll ( ( ) => { treeA = document . createElement ( "div" ) ; treeB = document . createElement ( "div" ) ; document . body . appendChild ( treeA ) ; document . body . appendChild ( treeB ) ; } ) ; afterAll ( ( ) => { treeA . parentNode ! . removeChild ( treeA ) ; treeB . parentNode ! . removeChild ( treeB ) ; } ) ; test ( "baseElement isolates trees from one another" , ( ) => { const { getByText : getByTextInA } = render ( ( ) => < div > Jekyll < /div>, { baseElement : treeA } ) ; const { getByText : getByTextInB } = render ( ( ) => < div > Hyde < /div>, { baseElement : treeB } ) ; expect ( ( ) => getByTextInA ( "Jekyll" ) ) . not . toThrow ( "Unable to find an element with the text: Jekyll." ) ; expect ( ( ) => getByTextInB ( "Jekyll" ) ) . toThrow ( "Unable to find an element with the text: Jekyll." ) ; expect ( ( ) => getByTextInA ( "Hyde" ) ) . toThrow ( "Unable to find an element with the text: Hyde." ) ; expect ( ( ) => getByTextInB ( "Hyde" ) ) . not . toThrow ( "Unable to find an element with the text: Hyde." ) ; } ) ;