diff --git a/Lib/html/parser.py b/Lib/html/parser.py
index 13c95c34e505c8..0a1dd3b7d3bfd2 100644
--- a/Lib/html/parser.py
+++ b/Lib/html/parser.py
@@ -12,6 +12,7 @@
import _markupbase
from html import unescape
+from html.entities import html5 as html5_entities
__all__ = ['HTMLParser']
@@ -23,6 +24,7 @@
entityref = re.compile('&([a-zA-Z][-.a-zA-Z0-9]*)[^a-zA-Z0-9]')
charref = re.compile('(?:[0-9]+|[xX][0-9a-fA-F]+)[^0-9a-fA-F]')
+attr_charref = re.compile(r'&(#[0-9]+|#[xX][0-9a-fA-F]+|[a-zA-Z][a-zA-Z0-9]*)[;=]?')
starttagopen = re.compile('<[a-zA-Z]')
piclose = re.compile('>')
@@ -57,6 +59,22 @@
# and the tag name, so maybe this should be fixed
endtagfind = re.compile(r'\s*([a-zA-Z][-.a-zA-Z0-9:_]*)\s*>')
+# Character reference processing logic specific to attribute values
+# See: https://html.spec.whatwg.org/multipage/parsing.html#named-character-reference-state
+def _replace_attr_charref(match):
+ ref = match.group(0)
+ # Numeric / hex char refs must always be unescaped
+ if ref.startswith(''):
+ return unescape(ref)
+ # Named character / entity references must only be unescaped
+ # if they are an exact match, and they are not followed by an equals sign
+ if not ref.endswith('=') and ref[1:] in html5_entities:
+ return unescape(ref)
+ # Otherwise do not unescape
+ return ref
+
+def _unescape_attrvalue(s):
+ return attr_charref.sub(_replace_attr_charref, s)
class HTMLParser(_markupbase.ParserBase):
@@ -323,7 +341,7 @@ def parse_starttag(self, i):
attrvalue[:1] == '"' == attrvalue[-1:]:
attrvalue = attrvalue[1:-1]
if attrvalue:
- attrvalue = unescape(attrvalue)
+ attrvalue = _unescape_attrvalue(attrvalue)
attrs.append((attrname.lower(), attrvalue))
k = m.end()
diff --git a/Lib/test/test_htmlparser.py b/Lib/test/test_htmlparser.py
index b42a611c62c0aa..4fdba06cf4cc92 100644
--- a/Lib/test/test_htmlparser.py
+++ b/Lib/test/test_htmlparser.py
@@ -348,18 +348,16 @@ def test_convert_charrefs(self):
collector = lambda: EventCollectorCharrefs()
self.assertTrue(collector().convert_charrefs)
charrefs = ['"', '"', '"', '"', '"', '"']
- # check charrefs in the middle of the text/attributes
- expected = [('starttag', 'a', [('href', 'foo"zar')]),
- ('data', 'a"z'), ('endtag', 'a')]
+ # check charrefs in the middle of the text
+ expected = [('starttag', 'a', []), ('data', 'a"z'), ('endtag', 'a')]
for charref in charrefs:
- self._run_check('a{0}z'.format(charref),
+ self._run_check('a{0}z'.format(charref),
expected, collector=collector())
- # check charrefs at the beginning/end of the text/attributes
- expected = [('data', '"'),
- ('starttag', 'a', [('x', '"'), ('y', '"X'), ('z', 'X"')]),
+ # check charrefs at the beginning/end of the text
+ expected = [('data', '"'), ('starttag', 'a', []),
('data', '"'), ('endtag', 'a'), ('data', '"')]
for charref in charrefs:
- self._run_check('{0}'
+ self._run_check('{0}'
'{0}{0}'.format(charref),
expected, collector=collector())
# check charrefs in