### Question:
OsmLoginPresenter implements OsmLoginFragmentContract.Presenter { @Override public void clickedOsmLoginButton() { preferences.setStringPreference(PreferenceList.OAUTH_VERIFIER, ""); preferences.setStringPreference(PreferenceList.OAUTH_TOKEN, ""); preferences.setStringPreference(PreferenceList.OAUTH_TOKEN_SECRET, ""); view.startOAuth(); } OsmLoginPresenter(OsmLoginFragmentContract.View view, SourceContract.Preferences preferences); @Override void clickedOsmLoginButton();  }### Answer:
@Test public void checkPreferencesAreCleared() { presenter.clickedOsmLoginButton(); verify(view).startOAuth(); }