Function xref_copy

src_classic/utils.py:5473–5507

Copy a PDF dictionary object to another one given their xref numbers. Args: doc: PDF document object source: source xref number target: target xref number, the xref must already exist keep: an optional list of 1st level keys in target that should not be

(doc: Document, source: int, target: int, *, keep: list = None)

# Copy XREF object to another XREF
# -------------------------------------------------------------------
def xref_copy(doc: Document, source: int, target: int, *, keep: list = None) -> None:
    """Copy a PDF dictionary object to another one given their xref numbers.

    Args:
        doc: PDF document object
        source: source xref number
        target: target xref number, the xref must already exist
        keep: an optional list of 1st level keys in target that should not be
              removed before copying.
    Notes:
        This works similar to the copy() method of dictionaries in Python. The
        source may be a stream object.
    """
    if doc.xref_is_stream(source):
        # read new xref stream, maintaining compression
        stream = doc.xref_stream_raw(source)
        doc.update_stream(
            target,
            stream,
            compress=False,  # keeps source compression
            new=True,  # in case target is no stream
        )

    # empty the target completely, observe exceptions
    if keep is None:
        keep = []
    for key in doc.xref_get_keys(target):
        if key in keep:
            continue
        doc.xref_set_key(target, key, "null")
    # copy over all source dict items
    for key in doc.xref_get_keys(source):
        item = doc.xref_get_key(source, key)
        doc.xref_set_key(target, key, item[1])
    return None