gh-144270: make SubElement parent and tag positional-only#144845
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NekoAsakura wants to merge 1 commit intopython:mainfrom
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gh-144270: make SubElement parent and tag positional-only#144845NekoAsakura wants to merge 1 commit intopython:mainfrom
NekoAsakura wants to merge 1 commit intopython:mainfrom
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The C accelerator implementations use PyArg_ParseTuple, which inherently enforces positional-only parameters. The Python fallback allowed these as keyword arguments, creating a behavioral mismatch. Make the tag parameter of Element.__init__ and the parent and tag parameters of SubElement positional-only to align with the C accelerator.
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Great. I've squashed the Element change from #144876 into this PR, you can close that one. |
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Issue: #144270
Make
parentandtagpositional-only inxml.etree.ElementTree.SubElementto match the C accelerator.The C implementation (
_elementtree.SubElement) usesPyArg_ParseTuple, which inherently makesparentandtagpositional-only. The Python fallback useddef SubElement(parent, tag, attrib={}, **extra):which allowedparentandtagas keyword arguments. This inconsistency meantSubElement(parent=e, tag="x")worked only when the C accelerator was unavailable.Fix: add
/aftertag→def SubElement(parent, tag, /, attrib={}, **extra):Changes
Lib/xml/etree/ElementTree.py: add/toSubElementsignatureLib/test/test_xml_etree.py: addtest_subelementcovering positional-only enforcement, keyword attrib, and kwargs-as-XML-attributes parityDoc/library/xml.etree.elementtree.rst: update signature and addversionchanged:: 3.15Note
Element.__init__has the same Python/C signature mismatch —tagis positional-only in the C version (PyArg_ParseTupleat_elementtree.c:419) but accepts keywords in the Pythonfallback (
ElementTree.py:167). I will create a separate issue for that to keep this PR focused.cpython/Lib/xml/etree/ElementTree.py
Line 167 in 23c488d
cpython/Modules/_elementtree.c
Lines 419 to 420 in 23c488d
📚 Documentation preview 📚: https://cpython-previews--144845.org.readthedocs.build/