assertCoordinatesEqualWallPoints(282, 40, 504, 20, wall6);
assertWallsAreJoined(wall4, wall5, wall6);
assertWallsAreJoined(wall5, wall6, wall2);
assertFalse("Split wall still present in home", frame.home.getWalls().contains(wall1));
// Undo operation and check undone state
tester.click(frame.undoButton);
assertSelectionContains(frame.home, wall1);
assertCoordinatesEqualWallPoints(60, 60, 504, 20, wall1);
assertWallsAreJoined(wall4, wall1, wall2);
assertTrue("Split wall not present in home", frame.home.getWalls().contains(wall1));
assertFalse("Wall still present in home", frame.home.getWalls().contains(wall5));