(merge 3.2) Issue #12451: The XInclude default loader of xml.etree now decodes

files from UTF-8 instead of the locale encoding if the encoding is not
specified. It now also opens XML files for the parser in binary mode instead of
the text mode to avoid encoding issues.

Lib/xml/etree/ElementInclude.py

@@ -67,7 +67,7 @@ class FatalIncludeError(SyntaxError):
 #
 # @param href Resource reference.
 # @param parse Parse mode.  Either "xml" or "text".
-# @param encoding Optional text encoding.
+# @param encoding Optional text encoding (UTF-8 by default for "text").
 # @return The expanded resource.  If the parse mode is "xml", this
 #    is an ElementTree instance.  If the parse mode is "text", this
 #    is a Unicode string.  If the loader fails, it can return None
@@ -75,13 +75,14 @@ class FatalIncludeError(SyntaxError):
 # @throws IOError If the loader fails to load the resource.
 
 def default_loader(href, parse, encoding=None):
-    file = open(href)
     if parse == "xml":
+        file = open(href, 'rb')
         data = ElementTree.parse(file).getroot()
     else:
+        if not encoding:
+            encoding = 'UTF-8'
+        file = open(href, 'r', encoding=encoding)
         data = file.read()
-        if encoding:
-            data = data.decode(encoding)
     file.close()
     return data
 

Misc/NEWS

@@ -200,6 +200,11 @@ Core and Builtins
 Library
 -------
 
+- Issue #12451: The XInclude default loader of xml.etree now decodes files from
+  UTF-8 instead of the locale encoding if the encoding is not specified. It now
+  also opens XML files for the parser in binary mode instead of the text mode
+  to avoid encoding issues.
+
 - Issue #12451: doctest.debug_script() doesn't create a temporary file
   anymore to avoid encoding issues.