diff --git a/Doc/library/xml.etree.elementtree.rst b/Doc/library/xml.etree.elementtree.rst
index 66090af00fa16e..ef74d0c852cd75 100644
--- a/Doc/library/xml.etree.elementtree.rst
+++ b/Doc/library/xml.etree.elementtree.rst
@@ -465,6 +465,53 @@ Reference
Functions
^^^^^^^^^
+.. function:: canonicalize(xml_data=None, *, out=None, from_file=None, **options)
+
+ `C14N 2.0 `_ transformation function.
+
+ Canonicalization is a way to normalise XML output in a way that allows
+ byte-by-byte comparisons and digital signatures. It reduced the freedom
+ that XML serializers have and instead generates a more constrained XML
+ representation. The main restrictions regard the placement of namespace
+ declarations, the ordering of attributes, and ignorable whitespace.
+
+ This function takes an XML data string (*xml_data*) or a file path or
+ file-like object (*from_file*) as input, converts it to the canonical
+ form, and writes it out using the *out* file(-like) object, if provided,
+ or returns it as a text string if not. The output file receives text,
+ not bytes. It should therefore be opened in text mode with ``utf-8``
+ encoding.
+
+ Typical uses::
+
+ xml_data = "..."
+ print(canonicalize(xml_data))
+
+ with open("c14n_output.xml", mode='w', encoding='utf-8') as out_file:
+ canonicalize(xml_data, out=out_file)
+
+ with open("c14n_output.xml", mode='w', encoding='utf-8') as out_file:
+ canonicalize(from_file="inputfile.xml", out=out_file)
+
+ The configuration *options* are as follows:
+
+ - *with_comments*: set to true to include comments (default: false)
+ - *strip_text*: set to true to strip whitespace before and after text content
+ (default: false)
+ - *rewrite_prefixes*: set to true to replace namespace prefixes by "n{number}"
+ (default: false)
+ - *qname_aware_tags*: a set of qname aware tag names in which prefixes
+ should be replaced in text content (default: empty)
+ - *qname_aware_attrs*: a set of qname aware attribute names in which prefixes
+ should be replaced in text content (default: empty)
+ - *exclude_attrs*: a set of attribute names that should not be serialised
+ - *exclude_tags*: a set of tag names that should not be serialised
+
+ In the option list above, "a set" refers to any collection or iterable of
+ strings, no ordering is expected.
+
+ .. versionadded:: 3.8
+
.. function:: Comment(text=None)
@@ -1114,6 +1161,19 @@ TreeBuilder Objects
.. versionadded:: 3.8
+.. class:: C14NWriterTarget(write, *, \
+ with_comments=False, strip_text=False, rewrite_prefixes=False, \
+ qname_aware_tags=None, qname_aware_attrs=None, \
+ exclude_attrs=None, exclude_tags=None)
+
+ A `C14N 2.0 `_ writer. Arguments are the
+ same as for the :func:`canonicalize` function. This class does not build a
+ tree but translates the callback events directly into a serialised form
+ using the *write* function.
+
+ .. versionadded:: 3.8
+
+
.. _elementtree-xmlparser-objects:
XMLParser Objects
diff --git a/Doc/whatsnew/3.8.rst b/Doc/whatsnew/3.8.rst
index bbc55ddd63418d..37570bcad52608 100644
--- a/Doc/whatsnew/3.8.rst
+++ b/Doc/whatsnew/3.8.rst
@@ -525,6 +525,10 @@ xml
external entities by default.
(Contributed by Christian Heimes in :issue:`17239`.)
+* The :mod:`xml.etree.ElementTree` module provides a new function
+ :func:`–xml.etree.ElementTree.canonicalize()` that implements C14N 2.0.
+ (Contributed by Stefan Behnel in :issue:`13611`.)
+
Optimizations
=============
diff --git a/Lib/test/test_xml_etree.py b/Lib/test/test_xml_etree.py
index 0abc42a173d930..a59a11f025da31 100644
--- a/Lib/test/test_xml_etree.py
+++ b/Lib/test/test_xml_etree.py
@@ -12,6 +12,7 @@
import itertools
import locale
import operator
+import os
import pickle
import sys
import textwrap
@@ -20,6 +21,7 @@
import warnings
import weakref
+from functools import partial
from itertools import product, islice
from test import support
from test.support import TESTFN, findfile, import_fresh_module, gc_collect, swap_attr
@@ -3527,6 +3529,231 @@ def test_correct_import_pyET(self):
self.assertIsInstance(pyET.Element.__init__, types.FunctionType)
self.assertIsInstance(pyET.XMLParser.__init__, types.FunctionType)
+
+# --------------------------------------------------------------------
+
+def c14n_roundtrip(xml, **options):
+ return pyET.canonicalize(xml, **options)
+
+
+class C14NTest(unittest.TestCase):
+ maxDiff = None
+
+ #
+ # simple roundtrip tests (from c14n.py)
+
+ def test_simple_roundtrip(self):
+ # Basics
+ self.assertEqual(c14n_roundtrip(""), '')
+ self.assertEqual(c14n_roundtrip(""), # FIXME
+ '')
+ self.assertEqual(c14n_roundtrip(""),
+ '')
+ self.assertEqual(c14n_roundtrip(""),
+ '')
+ self.assertEqual(c14n_roundtrip(""),
+ '')
+
+ # C14N spec
+ self.assertEqual(c14n_roundtrip("Hello, world!"),
+ 'Hello, world!')
+ self.assertEqual(c14n_roundtrip("2"),
+ '2')
+ self.assertEqual(c14n_roundtrip('"0" && value<"10" ?"valid":"error"]]>'),
+ 'value>"0" && value<"10" ?"valid":"error"')
+ self.assertEqual(c14n_roundtrip('''valid'''),
+ 'valid')
+ self.assertEqual(c14n_roundtrip(""),
+ '')
+ self.assertEqual(c14n_roundtrip(""),
+ '')
+ self.assertEqual(c14n_roundtrip(""),
+ '')
+
+ # fragments from PJ's tests
+ #self.assertEqual(c14n_roundtrip(""),
+ #'')
+
+ def test_c14n_exclusion(self):
+ xml = textwrap.dedent("""\
+
+
+ abtext
+
+ btext
+
+ dtext
+
+
+ """)
+ self.assertEqual(
+ c14n_roundtrip(xml, strip_text=True),
+ ''
+ 'abtext'
+ 'btext'
+ 'dtext'
+ '')
+ self.assertEqual(
+ c14n_roundtrip(xml, strip_text=True, exclude_attrs=['{http://example.com/x}attr']),
+ ''
+ 'abtext'
+ 'btext'
+ 'dtext'
+ '')
+ self.assertEqual(
+ c14n_roundtrip(xml, strip_text=True, exclude_tags=['{http://example.com/x}d']),
+ ''
+ 'abtext'
+ 'btext'
+ ''
+ '')
+ self.assertEqual(
+ c14n_roundtrip(xml, strip_text=True, exclude_attrs=['{http://example.com/x}attr'],
+ exclude_tags=['{http://example.com/x}d']),
+ ''
+ 'abtext'
+ 'btext'
+ ''
+ '')
+ self.assertEqual(
+ c14n_roundtrip(xml, strip_text=True, exclude_tags=['a', 'b']),
+ ''
+ 'dtext'
+ '')
+ self.assertEqual(
+ c14n_roundtrip(xml, exclude_tags=['a', 'b']),
+ '\n'
+ ' \n'
+ ' \n'
+ ' \n'
+ ' dtext\n'
+ ' \n'
+ '')
+ self.assertEqual(
+ c14n_roundtrip(xml, strip_text=True, exclude_tags=['{http://example.com/x}d', 'b']),
+ ''
+ ''
+ ''
+ '')
+ self.assertEqual(
+ c14n_roundtrip(xml, exclude_tags=['{http://example.com/x}d', 'b']),
+ '\n'
+ ' \n'
+ ' \n'
+ ' \n'
+ ' \n'
+ ' \n'
+ ' \n'
+ ' \n'
+ '')
+
+ #
+ # basic method=c14n tests from the c14n 2.0 specification. uses
+ # test files under xmltestdata/c14n-20.
+
+ # note that this uses generated C14N versions of the standard ET.write
+ # output, not roundtripped C14N (see above).
+
+ def test_xml_c14n2(self):
+ datadir = findfile("c14n-20", subdir="xmltestdata")
+ full_path = partial(os.path.join, datadir)
+
+ files = [filename[:-4] for filename in sorted(os.listdir(datadir))
+ if filename.endswith('.xml')]
+ input_files = [
+ filename for filename in files
+ if filename.startswith('in')
+ ]
+ configs = {
+ filename: {
+ # sequential
+ option.tag.split('}')[-1]: ((option.text or '').strip(), option)
+ for option in ET.parse(full_path(filename) + ".xml").getroot()
+ }
+ for filename in files
+ if filename.startswith('c14n')
+ }
+
+ tests = {
+ input_file: [
+ (filename, configs[filename.rsplit('_', 1)[-1]])
+ for filename in files
+ if filename.startswith(f'out_{input_file}_')
+ and filename.rsplit('_', 1)[-1] in configs
+ ]
+ for input_file in input_files
+ }
+
+ # Make sure we found all test cases.
+ self.assertEqual(30, len([
+ output_file for output_files in tests.values()
+ for output_file in output_files]))
+
+ def get_option(config, option_name, default=None):
+ return config.get(option_name, (default, ()))[0]
+
+ for input_file, output_files in tests.items():
+ for output_file, config in output_files:
+ keep_comments = get_option(
+ config, 'IgnoreComments') == 'true' # no, it's right :)
+ strip_text = get_option(
+ config, 'TrimTextNodes') == 'true'
+ rewrite_prefixes = get_option(
+ config, 'PrefixRewrite') == 'sequential'
+ if 'QNameAware' in config:
+ qattrs = [
+ f"{{{el.get('NS')}}}{el.get('Name')}"
+ for el in config['QNameAware'][1].findall(
+ '{http://www.w3.org/2010/xml-c14n2}QualifiedAttr')
+ ]
+ qtags = [
+ f"{{{el.get('NS')}}}{el.get('Name')}"
+ for el in config['QNameAware'][1].findall(
+ '{http://www.w3.org/2010/xml-c14n2}Element')
+ ]
+ else:
+ qtags = qattrs = None
+
+ # Build subtest description from config.
+ config_descr = ','.join(
+ f"{name}={value or ','.join(c.tag.split('}')[-1] for c in children)}"
+ for name, (value, children) in sorted(config.items())
+ )
+
+ with self.subTest(f"{output_file}({config_descr})"):
+ if input_file == 'inNsRedecl' and not rewrite_prefixes:
+ self.skipTest(
+ f"Redeclared namespace handling is not supported in {output_file}")
+ if input_file == 'inNsSuperfluous' and not rewrite_prefixes:
+ self.skipTest(
+ f"Redeclared namespace handling is not supported in {output_file}")
+ if 'QNameAware' in config and config['QNameAware'][1].find(
+ '{http://www.w3.org/2010/xml-c14n2}XPathElement') is not None:
+ self.skipTest(
+ f"QName rewriting in XPath text is not supported in {output_file}")
+
+ f = full_path(input_file + ".xml")
+ if input_file == 'inC14N5':
+ # Hack: avoid setting up external entity resolution in the parser.
+ with open(full_path('world.txt'), 'rb') as entity_file:
+ with open(f, 'rb') as f:
+ f = io.BytesIO(f.read().replace(b'&ent2;', entity_file.read()))
+
+ text = ET.canonicalize(
+ from_file=f,
+ with_comments=keep_comments,
+ strip_text=strip_text,
+ rewrite_prefixes=rewrite_prefixes,
+ qname_aware_tags=qtags, qname_aware_attrs=qattrs)
+
+ with open(full_path(output_file + ".xml"), 'r', encoding='utf8') as f:
+ expected = f.read()
+ if input_file == 'inC14N3':
+ # FIXME: cET resolves default attributes but ET does not!
+ expected = expected.replace(' attr="default"', '')
+ text = text.replace(' attr="default"', '')
+ self.assertEqual(expected, text)
+
# --------------------------------------------------------------------
@@ -3559,6 +3786,8 @@ def test_main(module=None):
XMLParserTest,
XMLPullParserTest,
BugsTest,
+ KeywordArgsTest,
+ C14NTest,
]
# These tests will only run for the pure-Python version that doesn't import
diff --git a/Lib/test/xmltestdata/c14n-20/c14nComment.xml b/Lib/test/xmltestdata/c14n-20/c14nComment.xml
new file mode 100644
index 00000000000000..e95aa302d04fdb
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/c14nComment.xml
@@ -0,0 +1,4 @@
+
+ true
+
+
diff --git a/Lib/test/xmltestdata/c14n-20/c14nDefault.xml b/Lib/test/xmltestdata/c14n-20/c14nDefault.xml
new file mode 100644
index 00000000000000..c1364142cc59bf
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/c14nDefault.xml
@@ -0,0 +1,3 @@
+
+
+
diff --git a/Lib/test/xmltestdata/c14n-20/c14nPrefix.xml b/Lib/test/xmltestdata/c14n-20/c14nPrefix.xml
new file mode 100644
index 00000000000000..fb233b42b1334f
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/c14nPrefix.xml
@@ -0,0 +1,4 @@
+
+ sequential
+
+
diff --git a/Lib/test/xmltestdata/c14n-20/c14nPrefixQname.xml b/Lib/test/xmltestdata/c14n-20/c14nPrefixQname.xml
new file mode 100644
index 00000000000000..23188eedbc2451
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/c14nPrefixQname.xml
@@ -0,0 +1,7 @@
+
+ sequential
+
+
+
+
+
diff --git a/Lib/test/xmltestdata/c14n-20/c14nPrefixQnameXpathElem.xml b/Lib/test/xmltestdata/c14n-20/c14nPrefixQnameXpathElem.xml
new file mode 100644
index 00000000000000..626fc48f410fa0
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/c14nPrefixQnameXpathElem.xml
@@ -0,0 +1,8 @@
+
+ sequential
+
+
+
+
+
+
diff --git a/Lib/test/xmltestdata/c14n-20/c14nQname.xml b/Lib/test/xmltestdata/c14n-20/c14nQname.xml
new file mode 100644
index 00000000000000..919e5903f5ce6e
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/c14nQname.xml
@@ -0,0 +1,6 @@
+
+
+
+
+
+
diff --git a/Lib/test/xmltestdata/c14n-20/c14nQnameElem.xml b/Lib/test/xmltestdata/c14n-20/c14nQnameElem.xml
new file mode 100644
index 00000000000000..0321f8061952e6
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/c14nQnameElem.xml
@@ -0,0 +1,6 @@
+
+
+
+
+
+
diff --git a/Lib/test/xmltestdata/c14n-20/c14nQnameXpathElem.xml b/Lib/test/xmltestdata/c14n-20/c14nQnameXpathElem.xml
new file mode 100644
index 00000000000000..c4890bc8b01d5e
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/c14nQnameXpathElem.xml
@@ -0,0 +1,7 @@
+
+
+
+
+
+
+
diff --git a/Lib/test/xmltestdata/c14n-20/c14nTrim.xml b/Lib/test/xmltestdata/c14n-20/c14nTrim.xml
new file mode 100644
index 00000000000000..ccb9cf65db7235
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/c14nTrim.xml
@@ -0,0 +1,4 @@
+
+ true
+
+
diff --git a/Lib/test/xmltestdata/c14n-20/doc.dtd b/Lib/test/xmltestdata/c14n-20/doc.dtd
new file mode 100644
index 00000000000000..5c5d544a0df845
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/doc.dtd
@@ -0,0 +1,6 @@
+
+
+
+
+
+
diff --git a/Lib/test/xmltestdata/c14n-20/doc.xsl b/Lib/test/xmltestdata/c14n-20/doc.xsl
new file mode 100644
index 00000000000000..a3f2348cc2f2b3
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/doc.xsl
@@ -0,0 +1,5 @@
+
+
+
diff --git a/Lib/test/xmltestdata/c14n-20/inC14N1.xml b/Lib/test/xmltestdata/c14n-20/inC14N1.xml
new file mode 100644
index 00000000000000..ed450c7341d382
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/inC14N1.xml
@@ -0,0 +1,14 @@
+
+
+
+
+
+
+Hello, world!
+
+
+
+
+
+
diff --git a/Lib/test/xmltestdata/c14n-20/inC14N2.xml b/Lib/test/xmltestdata/c14n-20/inC14N2.xml
new file mode 100644
index 00000000000000..74eeea147c3791
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/inC14N2.xml
@@ -0,0 +1,11 @@
+
+
+ A B
+
+ A
+
+ B
+ A B
+ C
+
+
diff --git a/Lib/test/xmltestdata/c14n-20/inC14N3.xml b/Lib/test/xmltestdata/c14n-20/inC14N3.xml
new file mode 100644
index 00000000000000..fea78213f1ae69
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/inC14N3.xml
@@ -0,0 +1,18 @@
+]>
+
+
+
+
+
+
+
+
+
+
+
+
+
+
diff --git a/Lib/test/xmltestdata/c14n-20/inC14N4.xml b/Lib/test/xmltestdata/c14n-20/inC14N4.xml
new file mode 100644
index 00000000000000..909a847435b86c
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/inC14N4.xml
@@ -0,0 +1,13 @@
+
+
+]>
+
+ First line
Second line
+ 2
+ "0" && value<"10" ?"valid":"error"]]>
+ valid
+
+
+
+
diff --git a/Lib/test/xmltestdata/c14n-20/inC14N5.xml b/Lib/test/xmltestdata/c14n-20/inC14N5.xml
new file mode 100644
index 00000000000000..501161bad5187f
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/inC14N5.xml
@@ -0,0 +1,12 @@
+
+
+
+
+
+]>
+
+ &ent1;, &ent2;!
+
+
+
diff --git a/Lib/test/xmltestdata/c14n-20/inC14N6.xml b/Lib/test/xmltestdata/c14n-20/inC14N6.xml
new file mode 100644
index 00000000000000..31e2071867257c
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/inC14N6.xml
@@ -0,0 +1,2 @@
+
+©
diff --git a/Lib/test/xmltestdata/c14n-20/inNsContent.xml b/Lib/test/xmltestdata/c14n-20/inNsContent.xml
new file mode 100644
index 00000000000000..b9924660ba6da3
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/inNsContent.xml
@@ -0,0 +1,4 @@
+
+ xsd:string
+ /soap-env:body/child::b:foo[@att1 != "c:val" and @att2 != 'xsd:string']
+
diff --git a/Lib/test/xmltestdata/c14n-20/inNsDefault.xml b/Lib/test/xmltestdata/c14n-20/inNsDefault.xml
new file mode 100644
index 00000000000000..3e0d323bad27c2
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/inNsDefault.xml
@@ -0,0 +1,3 @@
+
+
+
diff --git a/Lib/test/xmltestdata/c14n-20/inNsPushdown.xml b/Lib/test/xmltestdata/c14n-20/inNsPushdown.xml
new file mode 100644
index 00000000000000..daa67d83f15914
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/inNsPushdown.xml
@@ -0,0 +1,6 @@
+
+
+
+
+
+
diff --git a/Lib/test/xmltestdata/c14n-20/inNsRedecl.xml b/Lib/test/xmltestdata/c14n-20/inNsRedecl.xml
new file mode 100644
index 00000000000000..10bd97beda3baa
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/inNsRedecl.xml
@@ -0,0 +1,3 @@
+
+
+
diff --git a/Lib/test/xmltestdata/c14n-20/inNsSort.xml b/Lib/test/xmltestdata/c14n-20/inNsSort.xml
new file mode 100644
index 00000000000000..8e9fc01c647b24
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/inNsSort.xml
@@ -0,0 +1,4 @@
+
+
+
+
diff --git a/Lib/test/xmltestdata/c14n-20/inNsSuperfluous.xml b/Lib/test/xmltestdata/c14n-20/inNsSuperfluous.xml
new file mode 100644
index 00000000000000..f77720f7b0b09d
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/inNsSuperfluous.xml
@@ -0,0 +1,4 @@
+
+
+
+
diff --git a/Lib/test/xmltestdata/c14n-20/inNsXml.xml b/Lib/test/xmltestdata/c14n-20/inNsXml.xml
new file mode 100644
index 00000000000000..7520cf3fb9eb28
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/inNsXml.xml
@@ -0,0 +1,3 @@
+
+ data
+
diff --git a/Lib/test/xmltestdata/c14n-20/out_inC14N1_c14nComment.xml b/Lib/test/xmltestdata/c14n-20/out_inC14N1_c14nComment.xml
new file mode 100644
index 00000000000000..d98d16840c6bcc
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inC14N1_c14nComment.xml
@@ -0,0 +1,6 @@
+
+Hello, world!
+
+
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inC14N1_c14nDefault.xml b/Lib/test/xmltestdata/c14n-20/out_inC14N1_c14nDefault.xml
new file mode 100644
index 00000000000000..af9a9770578e9d
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inC14N1_c14nDefault.xml
@@ -0,0 +1,4 @@
+
+Hello, world!
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inC14N2_c14nDefault.xml b/Lib/test/xmltestdata/c14n-20/out_inC14N2_c14nDefault.xml
new file mode 100644
index 00000000000000..2afa15ccb36382
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inC14N2_c14nDefault.xml
@@ -0,0 +1,11 @@
+
+
+ A B
+
+ A
+
+ B
+ A B
+ C
+
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inC14N2_c14nTrim.xml b/Lib/test/xmltestdata/c14n-20/out_inC14N2_c14nTrim.xml
new file mode 100644
index 00000000000000..7a1dc32946bce3
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inC14N2_c14nTrim.xml
@@ -0,0 +1 @@
+A BABA BC
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inC14N3_c14nDefault.xml b/Lib/test/xmltestdata/c14n-20/out_inC14N3_c14nDefault.xml
new file mode 100644
index 00000000000000..662e108aa8a1e4
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inC14N3_c14nDefault.xml
@@ -0,0 +1,14 @@
+
+
+
+
+
+
+
+
+
+
+
+
+
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inC14N3_c14nPrefix.xml b/Lib/test/xmltestdata/c14n-20/out_inC14N3_c14nPrefix.xml
new file mode 100644
index 00000000000000..041e1ec8ebe59a
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inC14N3_c14nPrefix.xml
@@ -0,0 +1,14 @@
+
+
+
+
+
+
+
+
+
+
+
+
+
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inC14N3_c14nTrim.xml b/Lib/test/xmltestdata/c14n-20/out_inC14N3_c14nTrim.xml
new file mode 100644
index 00000000000000..4f35ad9662df3b
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inC14N3_c14nTrim.xml
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inC14N4_c14nDefault.xml b/Lib/test/xmltestdata/c14n-20/out_inC14N4_c14nDefault.xml
new file mode 100644
index 00000000000000..243d0e61f2e94f
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inC14N4_c14nDefault.xml
@@ -0,0 +1,10 @@
+
+ First line
+Second line
+ 2
+ value>"0" && value<"10" ?"valid":"error"
+ valid
+
+
+
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inC14N4_c14nTrim.xml b/Lib/test/xmltestdata/c14n-20/out_inC14N4_c14nTrim.xml
new file mode 100644
index 00000000000000..24d83ba8ab0012
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inC14N4_c14nTrim.xml
@@ -0,0 +1,2 @@
+First line
+Second line2value>"0" && value<"10" ?"valid":"error"valid
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inC14N5_c14nDefault.xml b/Lib/test/xmltestdata/c14n-20/out_inC14N5_c14nDefault.xml
new file mode 100644
index 00000000000000..c232e740aee4a7
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inC14N5_c14nDefault.xml
@@ -0,0 +1,3 @@
+
+ Hello, world!
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inC14N5_c14nTrim.xml b/Lib/test/xmltestdata/c14n-20/out_inC14N5_c14nTrim.xml
new file mode 100644
index 00000000000000..3fa84b1e986014
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inC14N5_c14nTrim.xml
@@ -0,0 +1 @@
+Hello, world!
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inC14N6_c14nDefault.xml b/Lib/test/xmltestdata/c14n-20/out_inC14N6_c14nDefault.xml
new file mode 100644
index 00000000000000..0be38f98cb1398
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inC14N6_c14nDefault.xml
@@ -0,0 +1 @@
+©
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inNsContent_c14nDefault.xml b/Lib/test/xmltestdata/c14n-20/out_inNsContent_c14nDefault.xml
new file mode 100644
index 00000000000000..62d7e004a44034
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inNsContent_c14nDefault.xml
@@ -0,0 +1,4 @@
+
+ xsd:string
+ /soap-env:body/child::b:foo[@att1 != "c:val" and @att2 != 'xsd:string']
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inNsContent_c14nPrefixQnameXpathElem.xml b/Lib/test/xmltestdata/c14n-20/out_inNsContent_c14nPrefixQnameXpathElem.xml
new file mode 100644
index 00000000000000..20e1c2e9d6dfb4
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inNsContent_c14nPrefixQnameXpathElem.xml
@@ -0,0 +1,4 @@
+
+ n1:string
+ /n3:body/child::n2:foo[@att1 != "c:val" and @att2 != 'xsd:string']
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inNsContent_c14nQnameElem.xml b/Lib/test/xmltestdata/c14n-20/out_inNsContent_c14nQnameElem.xml
new file mode 100644
index 00000000000000..db8680daa033d7
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inNsContent_c14nQnameElem.xml
@@ -0,0 +1,4 @@
+
+ xsd:string
+ /soap-env:body/child::b:foo[@att1 != "c:val" and @att2 != 'xsd:string']
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inNsContent_c14nQnameXpathElem.xml b/Lib/test/xmltestdata/c14n-20/out_inNsContent_c14nQnameXpathElem.xml
new file mode 100644
index 00000000000000..df3b21579fac5e
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inNsContent_c14nQnameXpathElem.xml
@@ -0,0 +1,4 @@
+
+ xsd:string
+ /soap-env:body/child::b:foo[@att1 != "c:val" and @att2 != 'xsd:string']
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inNsDefault_c14nDefault.xml b/Lib/test/xmltestdata/c14n-20/out_inNsDefault_c14nDefault.xml
new file mode 100644
index 00000000000000..674b076dd6d9a6
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inNsDefault_c14nDefault.xml
@@ -0,0 +1,3 @@
+
+
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inNsDefault_c14nPrefix.xml b/Lib/test/xmltestdata/c14n-20/out_inNsDefault_c14nPrefix.xml
new file mode 100644
index 00000000000000..83edaae91e7423
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inNsDefault_c14nPrefix.xml
@@ -0,0 +1,3 @@
+
+
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inNsPushdown_c14nDefault.xml b/Lib/test/xmltestdata/c14n-20/out_inNsPushdown_c14nDefault.xml
new file mode 100644
index 00000000000000..fa4f21b5d0af55
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inNsPushdown_c14nDefault.xml
@@ -0,0 +1,6 @@
+
+
+
+
+
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inNsPushdown_c14nPrefix.xml b/Lib/test/xmltestdata/c14n-20/out_inNsPushdown_c14nPrefix.xml
new file mode 100644
index 00000000000000..6d579200c9dc8c
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inNsPushdown_c14nPrefix.xml
@@ -0,0 +1,6 @@
+
+
+
+
+
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inNsRedecl_c14nDefault.xml b/Lib/test/xmltestdata/c14n-20/out_inNsRedecl_c14nDefault.xml
new file mode 100644
index 00000000000000..ba37f925103c70
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inNsRedecl_c14nDefault.xml
@@ -0,0 +1,3 @@
+
+
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inNsRedecl_c14nPrefix.xml b/Lib/test/xmltestdata/c14n-20/out_inNsRedecl_c14nPrefix.xml
new file mode 100644
index 00000000000000..af3bb2d6f062cd
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inNsRedecl_c14nPrefix.xml
@@ -0,0 +1,3 @@
+
+
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inNsSort_c14nDefault.xml b/Lib/test/xmltestdata/c14n-20/out_inNsSort_c14nDefault.xml
new file mode 100644
index 00000000000000..8a92c5c61c2c2c
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inNsSort_c14nDefault.xml
@@ -0,0 +1,4 @@
+
+
+
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inNsSort_c14nPrefix.xml b/Lib/test/xmltestdata/c14n-20/out_inNsSort_c14nPrefix.xml
new file mode 100644
index 00000000000000..8d44c84fe5d307
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inNsSort_c14nPrefix.xml
@@ -0,0 +1,4 @@
+
+
+
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inNsSuperfluous_c14nDefault.xml b/Lib/test/xmltestdata/c14n-20/out_inNsSuperfluous_c14nDefault.xml
new file mode 100644
index 00000000000000..6bb862d763d737
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inNsSuperfluous_c14nDefault.xml
@@ -0,0 +1,4 @@
+
+
+
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inNsSuperfluous_c14nPrefix.xml b/Lib/test/xmltestdata/c14n-20/out_inNsSuperfluous_c14nPrefix.xml
new file mode 100644
index 00000000000000..700a16d42a7746
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inNsSuperfluous_c14nPrefix.xml
@@ -0,0 +1,4 @@
+
+
+
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inNsXml_c14nDefault.xml b/Lib/test/xmltestdata/c14n-20/out_inNsXml_c14nDefault.xml
new file mode 100644
index 00000000000000..1689f3bf423dc5
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inNsXml_c14nDefault.xml
@@ -0,0 +1,3 @@
+
+ data
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inNsXml_c14nPrefix.xml b/Lib/test/xmltestdata/c14n-20/out_inNsXml_c14nPrefix.xml
new file mode 100644
index 00000000000000..38508a47f6b904
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inNsXml_c14nPrefix.xml
@@ -0,0 +1,3 @@
+
+ data
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inNsXml_c14nPrefixQname.xml b/Lib/test/xmltestdata/c14n-20/out_inNsXml_c14nPrefixQname.xml
new file mode 100644
index 00000000000000..867980f82bfa59
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inNsXml_c14nPrefixQname.xml
@@ -0,0 +1,3 @@
+
+ data
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/out_inNsXml_c14nQname.xml b/Lib/test/xmltestdata/c14n-20/out_inNsXml_c14nQname.xml
new file mode 100644
index 00000000000000..0300f9d562db30
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/out_inNsXml_c14nQname.xml
@@ -0,0 +1,3 @@
+
+ data
+
\ No newline at end of file
diff --git a/Lib/test/xmltestdata/c14n-20/world.txt b/Lib/test/xmltestdata/c14n-20/world.txt
new file mode 100644
index 00000000000000..04fea06420ca60
--- /dev/null
+++ b/Lib/test/xmltestdata/c14n-20/world.txt
@@ -0,0 +1 @@
+world
\ No newline at end of file
diff --git a/Lib/xml/etree/ElementTree.py b/Lib/xml/etree/ElementTree.py
index 5b26ac72fd1aae..645e999a0be6ca 100644
--- a/Lib/xml/etree/ElementTree.py
+++ b/Lib/xml/etree/ElementTree.py
@@ -87,6 +87,7 @@
"XML", "XMLID",
"XMLParser", "XMLPullParser",
"register_namespace",
+ "canonicalize", "C14NWriterTarget",
]
VERSION = "1.3.0"
@@ -1711,6 +1712,336 @@ def close(self):
del self.target, self._target
+# --------------------------------------------------------------------
+# C14N 2.0
+
+def canonicalize(xml_data=None, *, out=None, from_file=None, **options):
+ """Convert XML to its C14N 2.0 serialised form.
+
+ If *out* is provided, it must be a file or file-like object that receives
+ the serialised canonical XML output (text, not bytes) through its ``.write()``
+ method. To write to a file, open it in text mode with encoding "utf-8".
+ If *out* is not provided, this function returns the output as text string.
+
+ Either *xml_data* (an XML string) or *from_file* (a file path or
+ file-like object) must be provided as input.
+
+ The configuration options are the same as for the ``C14NWriterTarget``.
+ """
+ if xml_data is None and from_file is None:
+ raise ValueError("Either 'xml_data' or 'from_file' must be provided as input")
+ sio = None
+ if out is None:
+ sio = out = io.StringIO()
+
+ parser = XMLParser(target=C14NWriterTarget(out.write, **options))
+
+ if xml_data is not None:
+ parser.feed(xml_data)
+ parser.close()
+ elif from_file is not None:
+ parse(from_file, parser=parser)
+
+ return sio.getvalue() if sio is not None else None
+
+
+_looks_like_prefix_name = re.compile(r'^\w+:\w+$', re.UNICODE).match
+
+
+class C14NWriterTarget:
+ """
+ Canonicalization writer target for the XMLParser.
+
+ Serialises parse events to XML C14N 2.0.
+
+ The *write* function is used for writing out the resulting data stream
+ as text (not bytes). To write to a file, open it in text mode with encoding
+ "utf-8" and pass its ``.write`` method.
+
+ Configuration options:
+
+ - *with_comments*: set to true to include comments
+ - *strip_text*: set to true to strip whitespace before and after text content
+ - *rewrite_prefixes*: set to true to replace namespace prefixes by "n{number}"
+ - *qname_aware_tags*: a set of qname aware tag names in which prefixes
+ should be replaced in text content
+ - *qname_aware_attrs*: a set of qname aware attribute names in which prefixes
+ should be replaced in text content
+ - *exclude_attrs*: a set of attribute names that should not be serialised
+ - *exclude_tags*: a set of tag names that should not be serialised
+ """
+ def __init__(self, write, *,
+ with_comments=False, strip_text=False, rewrite_prefixes=False,
+ qname_aware_tags=None, qname_aware_attrs=None,
+ exclude_attrs=None, exclude_tags=None):
+ self._write = write
+ self._data = []
+ self._with_comments = with_comments
+ self._strip_text = strip_text
+ self._exclude_attrs = set(exclude_attrs) if exclude_attrs else None
+ self._exclude_tags = set(exclude_tags) if exclude_tags else None
+
+ self._rewrite_prefixes = rewrite_prefixes
+ if qname_aware_tags:
+ self._qname_aware_tags = set(qname_aware_tags)
+ else:
+ self._qname_aware_tags = None
+ if qname_aware_attrs:
+ self._find_qname_aware_attrs = set(qname_aware_attrs).intersection
+ else:
+ self._find_qname_aware_attrs = None
+
+ # Stack with globally and newly declared namespaces as (uri, prefix) pairs.
+ self._declared_ns_stack = [[
+ ("http://www.w3.org/XML/1998/namespace", "xml"),
+ ]]
+ # Stack with user declared namespace prefixes as (uri, prefix) pairs.
+ self._ns_stack = []
+ if not rewrite_prefixes:
+ self._ns_stack.append(list(_namespace_map.items()))
+ self._ns_stack.append([])
+ self._prefix_map = {}
+ self._preserve_space = [False]
+ self._pending_start = None
+ self._root_seen = False
+ self._root_done = False
+ self._ignored_depth = 0
+
+ def _iter_namespaces(self, ns_stack, _reversed=reversed):
+ for namespaces in _reversed(ns_stack):
+ if namespaces: # almost no element declares new namespaces
+ yield from namespaces
+
+ def _resolve_prefix_name(self, prefixed_name):
+ prefix, name = prefixed_name.split(':', 1)
+ for uri, p in self._iter_namespaces(self._ns_stack):
+ if p == prefix:
+ return f'{{{uri}}}{name}'
+ raise ValueError(f'Prefix {prefix} of QName "{prefixed_name}" is not declared in scope')
+
+ def _qname(self, qname, uri=None):
+ if uri is None:
+ uri, tag = qname[1:].rsplit('}', 1) if qname[:1] == '{' else ('', qname)
+ else:
+ tag = qname
+
+ prefixes_seen = set()
+ for u, prefix in self._iter_namespaces(self._declared_ns_stack):
+ if u == uri and prefix not in prefixes_seen:
+ return f'{prefix}:{tag}' if prefix else tag, tag, uri
+ prefixes_seen.add(prefix)
+
+ # Not declared yet => add new declaration.
+ if self._rewrite_prefixes:
+ if uri in self._prefix_map:
+ prefix = self._prefix_map[uri]
+ else:
+ prefix = self._prefix_map[uri] = f'n{len(self._prefix_map)}'
+ self._declared_ns_stack[-1].append((uri, prefix))
+ return f'{prefix}:{tag}', tag, uri
+
+ if not uri and '' not in prefixes_seen:
+ # No default namespace declared => no prefix needed.
+ return tag, tag, uri
+
+ for u, prefix in self._iter_namespaces(self._ns_stack):
+ if u == uri:
+ self._declared_ns_stack[-1].append((uri, prefix))
+ return f'{prefix}:{tag}' if prefix else tag, tag, uri
+
+ raise ValueError(f'Namespace "{uri}" is not declared in scope')
+
+ def data(self, data):
+ if not self._ignored_depth:
+ self._data.append(data)
+
+ def _flush(self, _join_text=''.join):
+ data = _join_text(self._data)
+ del self._data[:]
+ if self._strip_text and not self._preserve_space[-1]:
+ data = data.strip()
+ if self._pending_start is not None:
+ args, self._pending_start = self._pending_start, None
+ qname_text = data if data and _looks_like_prefix_name(data) else None
+ self._start(*args, qname_text)
+ if qname_text is not None:
+ return
+ if data and self._root_seen:
+ self._write(_escape_cdata_c14n(data))
+
+ def start_ns(self, prefix, uri):
+ if self._ignored_depth:
+ return
+ # we may have to resolve qnames in text content
+ if self._data:
+ self._flush()
+ self._ns_stack[-1].append((uri, prefix))
+
+ def start(self, tag, attrs):
+ if self._exclude_tags is not None and (
+ self._ignored_depth or tag in self._exclude_tags):
+ self._ignored_depth += 1
+ return
+ if self._data:
+ self._flush()
+
+ new_namespaces = []
+ self._declared_ns_stack.append(new_namespaces)
+
+ if self._qname_aware_tags is not None and tag in self._qname_aware_tags:
+ # Need to parse text first to see if it requires a prefix declaration.
+ self._pending_start = (tag, attrs, new_namespaces)
+ return
+ self._start(tag, attrs, new_namespaces)
+
+ def _start(self, tag, attrs, new_namespaces, qname_text=None):
+ if self._exclude_attrs is not None and attrs:
+ attrs = {k: v for k, v in attrs.items() if k not in self._exclude_attrs}
+
+ qnames = {tag, *attrs}
+ resolved_names = {}
+
+ # Resolve prefixes in attribute and tag text.
+ if qname_text is not None:
+ qname = resolved_names[qname_text] = self._resolve_prefix_name(qname_text)
+ qnames.add(qname)
+ if self._find_qname_aware_attrs is not None and attrs:
+ qattrs = self._find_qname_aware_attrs(attrs)
+ if qattrs:
+ for attr_name in qattrs:
+ value = attrs[attr_name]
+ if _looks_like_prefix_name(value):
+ qname = resolved_names[value] = self._resolve_prefix_name(value)
+ qnames.add(qname)
+ else:
+ qattrs = None
+ else:
+ qattrs = None
+
+ # Assign prefixes in lexicographical order of used URIs.
+ parse_qname = self._qname
+ parsed_qnames = {n: parse_qname(n) for n in sorted(
+ qnames, key=lambda n: n.split('}', 1))}
+
+ # Write namespace declarations in prefix order ...
+ if new_namespaces:
+ attr_list = [
+ ('xmlns:' + prefix if prefix else 'xmlns', uri)
+ for uri, prefix in new_namespaces
+ ]
+ attr_list.sort()
+ else:
+ # almost always empty
+ attr_list = []
+
+ # ... followed by attributes in URI+name order
+ if attrs:
+ for k, v in sorted(attrs.items()):
+ if qattrs is not None and k in qattrs and v in resolved_names:
+ v = parsed_qnames[resolved_names[v]][0]
+ attr_qname, attr_name, uri = parsed_qnames[k]
+ # No prefix for attributes in default ('') namespace.
+ attr_list.append((attr_qname if uri else attr_name, v))
+
+ # Honour xml:space attributes.
+ space_behaviour = attrs.get('{http://www.w3.org/XML/1998/namespace}space')
+ self._preserve_space.append(
+ space_behaviour == 'preserve' if space_behaviour
+ else self._preserve_space[-1])
+
+ # Write the tag.
+ write = self._write
+ write('<' + parsed_qnames[tag][0])
+ if attr_list:
+ write(''.join([f' {k}="{_escape_attrib_c14n(v)}"' for k, v in attr_list]))
+ write('>')
+
+ # Write the resolved qname text content.
+ if qname_text is not None:
+ write(_escape_cdata_c14n(parsed_qnames[resolved_names[qname_text]][0]))
+
+ self._root_seen = True
+ self._ns_stack.append([])
+
+ def end(self, tag):
+ if self._ignored_depth:
+ self._ignored_depth -= 1
+ return
+ if self._data:
+ self._flush()
+ self._write(f'')
+ self._preserve_space.pop()
+ self._root_done = len(self._preserve_space) == 1
+ self._declared_ns_stack.pop()
+ self._ns_stack.pop()
+
+ def comment(self, text):
+ if not self._with_comments:
+ return
+ if self._ignored_depth:
+ return
+ if self._root_done:
+ self._write('\n')
+ elif self._root_seen and self._data:
+ self._flush()
+ self._write(f'')
+ if not self._root_seen:
+ self._write('\n')
+
+ def pi(self, target, data):
+ if self._ignored_depth:
+ return
+ if self._root_done:
+ self._write('\n')
+ elif self._root_seen and self._data:
+ self._flush()
+ self._write(
+ f'' if data else f'')
+ if not self._root_seen:
+ self._write('\n')
+
+
+def _escape_cdata_c14n(text):
+ # escape character data
+ try:
+ # it's worth avoiding do-nothing calls for strings that are
+ # shorter than 500 character, or so. assume that's, by far,
+ # the most common case in most applications.
+ if '&' in text:
+ text = text.replace('&', '&')
+ if '<' in text:
+ text = text.replace('<', '<')
+ if '>' in text:
+ text = text.replace('>', '>')
+ if '\r' in text:
+ text = text.replace('\r', '
')
+ return text
+ except (TypeError, AttributeError):
+ _raise_serialization_error(text)
+
+
+def _escape_attrib_c14n(text):
+ # escape attribute value
+ try:
+ if '&' in text:
+ text = text.replace('&', '&')
+ if '<' in text:
+ text = text.replace('<', '<')
+ if '"' in text:
+ text = text.replace('"', '"')
+ if '\t' in text:
+ text = text.replace('\t', ' ')
+ if '\n' in text:
+ text = text.replace('\n', '
')
+ if '\r' in text:
+ text = text.replace('\r', '
')
+ return text
+ except (TypeError, AttributeError):
+ _raise_serialization_error(text)
+
+
+# --------------------------------------------------------------------
+
# Import the C accelerators
try:
# Element is going to be shadowed by the C implementation. We need to keep
diff --git a/Misc/NEWS.d/next/Library/2019-04-26-10-10-34.bpo-13611.XEF4bg.rst b/Misc/NEWS.d/next/Library/2019-04-26-10-10-34.bpo-13611.XEF4bg.rst
new file mode 100644
index 00000000000000..d01decb9617ab5
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2019-04-26-10-10-34.bpo-13611.XEF4bg.rst
@@ -0,0 +1,2 @@
+The xml.etree.ElementTree packages gained support for C14N 2.0 serialisation.
+Patch by Stefan Behnel.