[Python-checkins] bpo-40624: Add support for the XPath != operator in xml.etree (GH-22147)

Mon Nov 9 02:03:00 EST 2020

https://github.com/python/cpython/commit/97e8b1eaeaf3aa325c84ff2e13417c30414d0269
commit: 97e8b1eaeaf3aa325c84ff2e13417c30414d0269
branch: master
author: Ammar Askar <ammar at ammaraskar.com>
committer: scoder <stefan_ml at behnel.de>
date: 2020年11月09日T08:02:39+01:00
summary:
bpo-40624: Add support for the XPath != operator in xml.etree (GH-22147)
files:
A Misc/NEWS.d/next/Library/2020-09-08-03-19-04.bpo-40624.0-gYfx.rst
M Doc/library/xml.etree.elementtree.rst
M Lib/test/test_xml_etree.py
M Lib/xml/etree/ElementPath.py

diff --git a/Doc/library/xml.etree.elementtree.rst b/Doc/library/xml.etree.elementtree.rst
index f4bccf6609810..87f4ee347d604 100644
--- a/Doc/library/xml.etree.elementtree.rst
+++ b/Doc/library/xml.etree.elementtree.rst
@@ -455,6 +455,12 @@ Supported XPath syntax
 | | has the given value. The value cannot contain |
 | | quotes. |
 +-----------------------+------------------------------------------------------+
+| ``[@attrib!='value']``| Selects all elements for which the given attribute |
+| | does not have the given value. The value cannot |
+| | contain quotes. |
+| | |
+| | .. versionadded:: 3.10 |
++-----------------------+------------------------------------------------------+
 | ``[tag]`` | Selects all elements that have a child named |
 | | ``tag``. Only immediate children are supported. |
 +-----------------------+------------------------------------------------------+
@@ -463,10 +469,22 @@ Supported XPath syntax
 | | |
 | | .. versionadded:: 3.7 |
 +-----------------------+------------------------------------------------------+
+| ``[.!='text']`` | Selects all elements whose complete text content, |
+| | including descendants, does not equal the given |
+| | ``text``. |
+| | |
+| | .. versionadded:: 3.10 |
++-----------------------+------------------------------------------------------+
 | ``[tag='text']`` | Selects all elements that have a child named |
 | | ``tag`` whose complete text content, including |
 | | descendants, equals the given ``text``. |
 +-----------------------+------------------------------------------------------+
+| ``[tag!='text']`` | Selects all elements that have a child named |
+| | ``tag`` whose complete text content, including |
+| | descendants, does not equal the given ``text``. |
+| | |
+| | .. versionadded:: 3.10 |
++-----------------------+------------------------------------------------------+
 | ``[position]`` | Selects all elements that are located at the given |
 | | position. The position can be either an integer |
 | | (1 is the first position), the expression ``last()`` |
diff --git a/Lib/test/test_xml_etree.py b/Lib/test/test_xml_etree.py
index 3f1f3781e488c..fd4a38527fde0 100644
--- a/Lib/test/test_xml_etree.py
+++ b/Lib/test/test_xml_etree.py
@@ -2852,8 +2852,12 @@ def test_findall(self):
 ['tag'] * 3)
 self.assertEqual(summarize_list(e.findall('.//tag[@class="a"]')),
 ['tag'])
+ self.assertEqual(summarize_list(e.findall('.//tag[@class!="a"]')),
+ ['tag'] * 2)
 self.assertEqual(summarize_list(e.findall('.//tag[@class="b"]')),
 ['tag'] * 2)
+ self.assertEqual(summarize_list(e.findall('.//tag[@class!="b"]')),
+ ['tag'])
 self.assertEqual(summarize_list(e.findall('.//tag[@id]')),
 ['tag'])
 self.assertEqual(summarize_list(e.findall('.//section[tag]')),
@@ -2875,6 +2879,19 @@ def test_findall(self):
 self.assertEqual(summarize_list(e.findall(".//section[ tag = 'subtext' ]")),
 ['section'])
 
+ # Negations of above tests. They match nothing because the sole section
+ # tag has subtext.
+ self.assertEqual(summarize_list(e.findall(".//section[tag!='subtext']")),
+ [])
+ self.assertEqual(summarize_list(e.findall(".//section[tag !='subtext']")),
+ [])
+ self.assertEqual(summarize_list(e.findall(".//section[tag!= 'subtext']")),
+ [])
+ self.assertEqual(summarize_list(e.findall(".//section[tag != 'subtext']")),
+ [])
+ self.assertEqual(summarize_list(e.findall(".//section[ tag != 'subtext' ]")),
+ [])
+
 self.assertEqual(summarize_list(e.findall(".//tag[.='subtext']")),
 ['tag'])
 self.assertEqual(summarize_list(e.findall(".//tag[. ='subtext']")),
@@ -2890,6 +2907,24 @@ def test_findall(self):
 self.assertEqual(summarize_list(e.findall(".//tag[.= ' subtext']")),
 [])
 
+ # Negations of above tests.
+ # Matches everything but the tag containing subtext
+ self.assertEqual(summarize_list(e.findall(".//tag[.!='subtext']")),
+ ['tag'] * 3)
+ self.assertEqual(summarize_list(e.findall(".//tag[. !='subtext']")),
+ ['tag'] * 3)
+ self.assertEqual(summarize_list(e.findall('.//tag[.!= "subtext"]')),
+ ['tag'] * 3)
+ self.assertEqual(summarize_list(e.findall('.//tag[ . != "subtext" ]')),
+ ['tag'] * 3)
+ self.assertEqual(summarize_list(e.findall(".//tag[. != 'subtext']")),
+ ['tag'] * 3)
+ # Matches all tags.
+ self.assertEqual(summarize_list(e.findall(".//tag[. != 'subtext ']")),
+ ['tag'] * 4)
+ self.assertEqual(summarize_list(e.findall(".//tag[.!= ' subtext']")),
+ ['tag'] * 4)
+
 # duplicate section => 2x tag matches
 e[1] = e[2]
 self.assertEqual(summarize_list(e.findall(".//section[tag = 'subtext']")),
diff --git a/Lib/xml/etree/ElementPath.py b/Lib/xml/etree/ElementPath.py
index d318e65d84a4a..1cbd8399d14c5 100644
--- a/Lib/xml/etree/ElementPath.py
+++ b/Lib/xml/etree/ElementPath.py
@@ -65,8 +65,9 @@
 r"//?|"
 r"\.\.|"
 r"\(\)|"
+ r"!=|"
 r"[/.*:\[\]\(\)@=])|"
- r"((?:\{[^}]+\})?[^/\[\]\(\)@=\s]+)|"
+ r"((?:\{[^}]+\})?[^/\[\]\(\)@!=\s]+)|"
 r"\s+"
 )
 
@@ -253,15 +254,19 @@ def select(context, result):
 if elem.get(key) is not None:
 yield elem
 return select
- if signature == "@-='":
- # [@attribute='value']
+ if signature == "@-='" or signature == "@-!='":
+ # [@attribute='value'] or [@attribute!='value']
 key = predicate[1]
 value = predicate[-1]
 def select(context, result):
 for elem in result:
 if elem.get(key) == value:
 yield elem
- return select
+ def select_negated(context, result):
+ for elem in result:
+ if (attr_value := elem.get(key)) is not None and attr_value != value:
+ yield elem
+ return select_negated if '!=' in signature else select
 if signature == "-" and not re.match(r"\-?\d+$", predicate[0]):
 # [tag]
 tag = predicate[0]
@@ -270,8 +275,10 @@ def select(context, result):
 if elem.find(tag) is not None:
 yield elem
 return select
- if signature == ".='" or (signature == "-='" and not re.match(r"\-?\d+$", predicate[0])):
- # [.='value'] or [tag='value']
+ if signature == ".='" or signature == ".!='" or (
+ (signature == "-='" or signature == "-!='")
+ and not re.match(r"\-?\d+$", predicate[0])):
+ # [.='value'] or [tag='value'] or [.!='value'] or [tag!='value']
 tag = predicate[0]
 value = predicate[-1]
 if tag:
@@ -281,12 +288,22 @@ def select(context, result):
 if "".join(e.itertext()) == value:
 yield elem
 break
+ def select_negated(context, result):
+ for elem in result:
+ for e in elem.iterfind(tag):
+ if "".join(e.itertext()) != value:
+ yield elem
+ break
 else:
 def select(context, result):
 for elem in result:
 if "".join(elem.itertext()) == value:
 yield elem
- return select
+ def select_negated(context, result):
+ for elem in result:
+ if "".join(elem.itertext()) != value:
+ yield elem
+ return select_negated if '!=' in signature else select
 if signature == "-" or signature == "-()" or signature == "-()-":
 # [index] or [last()] or [last()-index]
 if signature == "-":
diff --git a/Misc/NEWS.d/next/Library/2020-09-08-03-19-04.bpo-40624.0-gYfx.rst b/Misc/NEWS.d/next/Library/2020-09-08-03-19-04.bpo-40624.0-gYfx.rst
new file mode 100644
index 0000000000000..78bad6e4686be
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2020-09-08-03-19-04.bpo-40624.0-gYfx.rst
@@ -0,0 +1 @@
+Added support for the XPath ``!=`` operator in xml.etree
