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.
The API documentation for [findtext](https://docs.python.org/3/library/xml.etree.elementtree.html#xml.etree.ElementTree.Element.findtext) states that this function gives back an empty string on "no text content." With the previous implementation, this would give back a empty string even on text content values such as 0 or False. This patch attempts to resolve that by only giving back an empty string if the text attribute is set to `None`. Resolves#91447.
Automerge-Triggered-By: GH:gvanrossum
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.
* bpo-20928: bring elementtree's XInclude support en-par with the implementation in lxml by adding support for recursive includes and a base-URL.
* bpo-20928: Support xincluding the same file multiple times, just not recursively.
* bpo-20928: Add 'max_depth' parameter to xinclude that limits the maximum recursion depth to 6 by default.
* Add news entry for updated ElementInclude support
* 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.
