b.v.VersionedFile(object) : class documentation

Add a single text on top of the versioned file.

        Must raise RevisionAlreadyPresent if the new version is
        already present in file history.

        Must raise RevisionNotPresent if any of the given parents are
        not present in file history.

        :param lines: A list of lines. Each line must be a bytestring. And all
            of them except the last must be terminated with 
 and contain no
            other 
's. The last line may either contain no 
's or a single
            terminated 
. If the lines list does meet this constraint the add
            routine may error or may succeed - but you will be unable to read
            the data back accurately. (Checking the lines have been split
            correctly is expensive and extremely unlikely to catch bugs so it
            is not done at runtime unless check_content is True.)
        :param parent_texts: An optional dictionary containing the opaque
            representations of some or all of the parents of version_id to
            allow delta optimisations.  VERY IMPORTANT: the texts must be those
            returned by add_lines or data corruption can be caused.
        :param left_matching_blocks: a hint about which areas are common
            between the text and its left-hand-parent.  The format is
            the SequenceMatcher.get_matching_blocks format.
        :param nostore_sha: Raise ExistingContent and do not add the lines to
            the versioned file if the digest of the lines matches this.
        :param random_id: If True a random id has been selected rather than
            an id determined by some deterministic process such as a converter
            from a foreign VCS. When True the backend may choose not to check
            for uniqueness of the resulting key within the versioned file, so
            this should only be done when the result is expected to be unique
            anyway.
        :param check_content: If True, the lines supplied are verified to be
            bytestrings that are correctly formed lines.
        :return: The text sha1, the number of bytes in the text, and an opaque
                 representation of the inserted version which can be provided
                 back to future add_lines calls in the parent_texts dictionary.
        

Return a list of (version-id, line) tuples for version_id.

:raise RevisionNotPresent: If the given version is
not present in file history.

Iterate over the lines in the versioned file from version_ids.

       This may return lines from other versions. Each item the returned
       iterator yields is a tuple of a line and a text version that that line
       is present in (not introduced in).

       Ordering of results is in whatever order is most suitable for the
       underlying storage format.

       If a progress bar is supplied, it may be used to indicate progress.
       The caller is responsible for cleaning up progress bars (because this
       is an iterator).

       NOTES: Lines are normalised: they will all have 
terminators.
              Lines are returned in arbitrary order.

       :return: An iterator over (line, version_id).