@Test
  public void getContentInputStreamForLatestVersion() throws Exception {
    XWikiDocument document = mock(XWikiDocument.class);
    when(document.getDocumentReference())
        .thenReturn(new DocumentReference("wiki", "Space", "Page"));

    when(this.oldcore
            .getXWikiContext()
            .getWiki()
            .getDocument(document.getDocumentReference(), this.oldcore.getXWikiContext()))
        .thenReturn(document);

    XWikiAttachment attachment = new XWikiAttachment(document, "file.txt");
    when(document.getAttachment(attachment.getFilename())).thenReturn(attachment);
    attachment.setVersion("3.5");

    try {
      attachment.getContentInputStream(this.oldcore.getXWikiContext());
      fail();
    } catch (NullPointerException e) {
      // Expected because the attachment content is not set. The attachment content is normally set
      // by the
      // loadAttachmentContent call we verify below.
    }

    verify(document).loadAttachmentContent(attachment, this.oldcore.getXWikiContext());
  }
  @Test
  public void testAuthorWithoutDocument() throws Exception {
    EntityReferenceSerializer<String> compactWikiEntityReferenceSerializer =
        this.oldcore.getMocker().getInstance(EntityReferenceSerializer.TYPE_STRING, "compactwiki");
    AttachmentReferenceResolver<String> currentAttachmentReferenceResolver =
        this.oldcore.getMocker().getInstance(AttachmentReferenceResolver.TYPE_STRING, "current");
    DocumentReferenceResolver<EntityReference> explicitDocumentReferenceResolver =
        this.oldcore
            .getMocker()
            .registerMockComponent(DocumentReferenceResolver.TYPE_REFERENCE, "explicit");
    EntityReferenceResolver<String> xclassEntityReferenceResolver =
        this.oldcore
            .getMocker()
            .registerMockComponent(EntityReferenceResolver.TYPE_STRING, "xclass");

    XWikiAttachment attachment = new XWikiAttachment(null, "filename");
    DocumentReference currentDocumentReference =
        new DocumentReference("currentWiki", "currentSpage", "currentPage");
    AttachmentReference attachmentReference =
        new AttachmentReference(attachment.getFilename(), currentDocumentReference);

    // getAuthor() based on getAuthorReference()
    DocumentReference userReference = new DocumentReference("userwiki", "userspace", "userpage");
    attachment.setAuthorReference(userReference);
    assertEquals(userReference, attachment.getAuthorReference());
    when(currentAttachmentReferenceResolver.resolve(attachment.getFilename()))
        .thenReturn(attachmentReference);
    when(compactWikiEntityReferenceSerializer.serialize(userReference, attachmentReference))
        .thenReturn("stringUserReference");
    assertEquals("stringUserReference", attachment.getAuthor());

    // getAuthorReference() based on getAuthor()
    attachment.setAuthor("author");
    assertEquals("author", attachment.getAuthor());
    userReference = new DocumentReference("wiki", "XWiki", "author");
    EntityReference relativeUserReference =
        userReference.removeParent(userReference.getWikiReference());
    when(xclassEntityReferenceResolver.resolve("author", EntityType.DOCUMENT))
        .thenReturn(relativeUserReference);
    when(explicitDocumentReferenceResolver.resolve(
            relativeUserReference, attachment.getReference()))
        .thenReturn(userReference);
    assertEquals(userReference, attachment.getAuthorReference());
  }
  @Test
  public void getContentInputStreamFromArchive() throws Exception {
    XWikiDocument document = mock(XWikiDocument.class);
    when(document.getDocumentReference())
        .thenReturn(new DocumentReference("wiki", "Space", "Page"));

    when(this.oldcore
            .getXWikiContext()
            .getWiki()
            .getDocument(document.getDocumentReference(), this.oldcore.getXWikiContext()))
        .thenReturn(document);

    XWikiAttachment attachment = new XWikiAttachment(document, "file.txt");
    attachment.setVersion("3.5");

    XWikiAttachment newAttachment = new XWikiAttachment(document, attachment.getFilename());
    newAttachment.setVersion("5.1");
    when(document.getAttachment(attachment.getFilename())).thenReturn(newAttachment);

    XWikiAttachmentContent content = mock(XWikiAttachmentContent.class);
    when(content.getContentInputStream()).thenReturn(mock(InputStream.class));

    XWikiAttachment archivedAttachment = new XWikiAttachment(document, attachment.getFilename());
    archivedAttachment.setAttachment_content(content);

    XWikiAttachmentArchive archive = mock(XWikiAttachmentArchive.class);
    when(archive.getRevision(attachment, attachment.getVersion(), this.oldcore.getXWikiContext()))
        .thenReturn(archivedAttachment);

    AttachmentVersioningStore store = mock(AttachmentVersioningStore.class);
    when(this.oldcore.getXWikiContext().getWiki().getAttachmentVersioningStore()).thenReturn(store);
    when(store.loadArchive(attachment, this.oldcore.getXWikiContext(), true)).thenReturn(archive);

    assertSame(
        content.getContentInputStream(),
        attachment.getContentInputStream(this.oldcore.getXWikiContext()));
  }
  /**
   * Get an old revision of the attachment which this is an archive of.
   *
   * @param attachment This attachment will be used to get the document to associate the attachment
   *     revision with.
   * @param rev a String representation of the version to load.
   * @param context the context for the request which needed this revision.
   * @return an XWikiAttachment for the given revision.
   * @throws XWikiException if any Exception is thrown while getting the revision.
   */
  public XWikiAttachment getRevision(
      final XWikiAttachment attachment, final String rev, final XWikiContext context)
      throws XWikiException {
    try {
      final Archive rcsArchive = getRCSArchive();

      if (rcsArchive == null) {
        return null;
      }

      final Version version = rcsArchive.getRevisionVersion(rev);
      if (version == null) {
        return null;
      }
      final Object[] lines = rcsArchive.getRevision(version);
      final StringBuffer content = new StringBuffer();
      for (int i = 0; i < lines.length; i++) {
        String line = lines[i].toString();
        content.append(line);
        if (i != lines.length - 1) {
          content.append("\n");
        }
      }

      final String scontent = content.toString();
      final XWikiAttachment revattach = new XWikiAttachment();
      revattach.fromXML(scontent);
      revattach.setDoc(attachment.getDoc());
      revattach.setVersion(rev);
      return revattach;
    } catch (Exception e) {
      final Object[] args = {attachment.getFilename()};
      throw new XWikiException(
          XWikiException.MODULE_XWIKI_STORE,
          XWikiException.ERROR_XWIKI_STORE_ATTACHMENT_ARCHIVEFORMAT,
          GENERIC_EXCEPTION_MESSAGE,
          e,
          args);
    }
  }
  /**
   * Unit test for <a href="http://jira.xwiki.org/browse/XWIKI-9075">XWIKI-9075</a> to prove that
   * calling {@code fromXML} doesn't set the metadata dirty flag.
   *
   * <p>Note: I think there's a bug in that fromXML should return a new instance of XWikiAttachment
   * and not modify the current one as this would mean changing its identity...
   */
  @Test
  public void fromXML() throws Exception {
    XWikiAttachment attachment = new XWikiAttachment();
    attachment.fromXML(
        "<attachment>\n"
            + "<filename>XWikiLogo.png</filename>\n"
            + "<filesize>1390</filesize>\n"
            + "<mimetype>image/png2</mimetype>\n"
            + "<author>xwiki:XWiki.Admin</author>\n"
            + "<date>1252454400000</date>\n"
            + "<version>1.1</version>\n"
            + "<comment/>\n"
            + "<content>MDEyMzQ1Njc4OQ==</content>\n"
            + "</attachment>");

    assertEquals("XWikiLogo.png", attachment.getFilename());
    assertEquals(new Date(1252454400000L), attachment.getDate());
    assertEquals("1.1", attachment.getVersion());
    assertEquals("0123456789", IOUtils.toString(attachment.getContentInputStream(null)));
    assertEquals("image/png2", attachment.getMimeType());
    assertEquals("image/png2", attachment.getMimeType(null));

    assertFalse(attachment.isMetaDataDirty());
  }