xml.dom.pulldom DOMEventStream drops SAX events produced by parser.close()

Bug report

Bug description:

Issue

DOMEventStream.getEvent() silently drops SAX events that are produced when parser.close() is called at end-of-stream. When the stream is exhausted, getEvent() calls self.parser.close() and immediately returns None without checking whether close() generated new events. This causes END_ELEMENT and other trailing events to be lost when bufsize causes the final tag to be split across reads.

Reproducer

import io
from xml.dom.pulldom import parse

events = list(parse(io.BytesIO(b'<a></a>'), bufsize=2))
print([e for e, _ in events])
# ['START_DOCUMENT', 'START_ELEMENT'] — END_ELEMENT is missing

Iterating the DOMEventStream (via list()) internally calls getEvent(), which is where the bug lives.

CPython versions tested on:

CPython main branch

Operating systems tested on:

No response

Linked PRs

• gh-145262

从 DOMEventStream.getEvent() 开始，issue 指出 parser.close() 可能会产生未被检查的事件。使用 bufsize=2 运行提供的 BytesIO reproducer，并验证迭代会保留末尾的 END_ELEMENT 事件；链接的 PR gh-145262 表明相关工作已经在进行中。