anchor.diff:    ExtractToStreamHelper := DoExtractToStreamHelper;
     InsertHelper := DoInsertHelper;
     InsertFromStreamHelper := DoInsertFromStreamHelper;
  +  TestHelper := DoTestHelper;
   end;
   {----------------------------------------------------------------------------}
   procedure TAbZipArchive.DoExtractHelper(Sender : TObject;
  
positive.code:   Item : TAbArchiveItem; OutStream, InStream : TStream);
  begin
    AbZipFromStream(TAbZipArchive(Sender), TAbZipItem(Item), OutStream, InStream);
  end;
  
  {----------------------------------------------------------------------------}
  
negative.code: begin
    Result := VerifyZip(aStream);
  end;
  { -------------------------------------------------------------------------- }
  procedure TAbZipArchiveTests.TestTestItemAt;
  var
    Arc: TAbZipArchive;
  begin
    Arc := TAbZipArchive.Create(MPLDir + 'MPL.zip', fmOpenRead);
    try
      Arc.Load;
      Arc.TestItemAt(0);
      Check(True);
    finally
      Arc.Free;
    end;
  end;
  { -------------------------------------------------------------------------- }
  procedure TAbZipArchiveTests.TestTestItemAtCorrupt;
  var
    Arc: TAbZipArchive;
  begin
    Arc := TAbZipArchive.Create(TestFileDir + 'CorruptMPL.zip', fmOpenRead);
    try
      Arc.Load;
      try
        Arc.TestItemAt(0);
      except
        on E: Exception do
          Check((E is EAbZipBadCRC) or (E is EAbZipInvalidLFH));
      end;
    finally
      Arc.Free;
    end;
  end;
  
  
  {----------------------------------------------------------------------------}
  { TAbZipDecompressTest }
  