@Override
    public void deleteAll() {
        try {
            this.indexWriter.deleteAll();
            this.searcherManager.maybeRefreshBlocking();
            this.indexWriter.commit();
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }
@Test
    void shouldDeleteAll() throws IOException {
        this.searchEngine.deleteAll();

        verify(this.indexWriter).deleteAll();
        verify(this.searcherManager).maybeRefreshBlocking();
        verify(this.indexWriter).commit();
    }