### Question:
DocumentChangesCollector implements DocumentListener { @NotNull public List<? extends TextChange> getChanges() { return myChanges; }  @Override void beforeDocumentChange(DocumentEvent event); @Override void documentChanged(DocumentEvent event); @NotNull List<? extends TextChange> getChanges(); void setCollectChanges(boolean collectChanges); void reset();  }### Answer:
@Test public void emptyCollector() { assertNotNull(myCollector.getChanges()); }