Allow controlling Expat >=2.6.0 reparse deferral (CVE-2023-52425) by adding five new methods:
- `xml.etree.ElementTree.XMLParser.flush`
- `xml.etree.ElementTree.XMLPullParser.flush`
- `xml.parsers.expat.xmlparser.GetReparseDeferralEnabled`
- `xml.parsers.expat.xmlparser.SetReparseDeferralEnabled`
- `xml.sax.expatreader.ExpatParser.flush`
Based on the "flush" idea from https://github.com/python/cpython/pull/115138#issuecomment-1932444270 .
### Notes
- Please treat as a security fix related to CVE-2023-52425.
Includes code suggested-by: Snild Dolkow <snild@sony.com>
and by core dev Serhiy Storchaka.
Prior to gh-114269, the iterator returned by ElementTree.iterparse was
initialized with the root attribute as None. This restores the previous
behavior.
The iterator returned by ElementTree.iterparse() may hold on to a file
descriptor. The reference cycle prevented prompt clean-up of the file
descriptor if the returned iterator was not exhausted.
When testing element truth values, emit a DeprecationWarning in all implementations.
This had emitted a FutureWarning in the rarely used python-only implementation since ~2.7 and has always been documented as a behavior not to rely on.
Matching an element in a tree search but having it test False can be unexpected. Raising the warning enables making the choice to finally raise an exception for this ambiguous behavior in the future.
xml.etree: Remove the ElementTree.Element.copy() method of the pure
Python implementation, deprecated in Python 3.10, use the copy.copy()
function instead. The C implementation of xml.etree has no copy()
method, only a __copy__() method.
Suppress writing an XML declaration in open files in ElementTree.write()
with encoding='unicode' and xml_declaration=None.
If file patch is passed to ElementTree.write() with encoding='unicode',
always open a new file in UTF-8.
ElementTree method write() and function tostring() now use the text file's
encoding ("UTF-8" if not available) instead of locale encoding in XML
declaration when encoding="unicode" is specified.
* bpo-39011: Preserve line endings within attributes
Line endings within attributes were previously normalized to "\n" in Py3.7/3.8.
This patch removes that normalization, as line endings which were
replaced by entity numbers should be preserved in original form.
* Implement C14N 2.0 as a new canonicalize() function in ElementTree.
Missing features:
- prefix renaming in XPath expressions (tag and attribute text is supported)
- preservation of original prefixes given redundant namespace declarations
* bpo-36673: Implement comment/PI parsing support for the TreeBuilder in ElementTree.
* bpo-36673: Rewrite the comment/PI factory handling for the TreeBuilder in "_elementtree" to make it use the same factories as the ElementTree module, and to make it explicit when the comments/PIs are inserted into the tree and when they are not (which is the default).
Add new keyword arguments "default_namespace" and "xml_declaration" to functions ET.tostring() and ET.tostringlist(), as known from ElementTree.write().
It is now guarantied that children of xml.etree.ElementTree.Element
are Elements (at least in C implementation). Previously methods
__setitem__(), __setstate__() and __deepcopy__() could be used for
adding non-Element children.
* Fix multiple typos in code comments
* Add spacing in comments (test_logging.py, test_math.py)
* Fix spaces at the beginning of comments in test_logging.py
Element.getiterator() and the html parameter of XMLParser() were
deprecated only in the documentation (since Python 3.2 and 3.4 correspondintly).
Now using them emits a deprecation warning.
* Don’t need check_warnings any more.
I was confused by the text saying that read_events "iterated", since it
actually returns an iterator (that's what a generator does) that the
caller must then iterate. So I tidied up the language. I'm not sure
what the sentence "Events provided in a previous call to read_events()
will not be yielded again." is trying to convey, so I didn't try to fix that.
Also fixed a couple more news items.