Updated ElementBase.__delitem__ and added unit tests.

sleekxmpp/xmlstream/stanzabase.py

@@ -269,6 +269,44 @@ class ElementBase(object):
             self.plugins[attrib][attrib] = value
         return self
 
+    def __delitem__(self, attrib):
+        """
+        Delete the value of a stanza interface using dictionary-like syntax.
+
+        Example:
+            >>> msg['body'] = "Hi!"
+            >>> msg['body']
+            'Hi!'
+            >>> del msg['body']
+            >>> msg['body']
+            ''
+
+        Stanza interfaces are typically mapped directly to the underlyig XML
+        object, but can be overridden by the presence of a delAttrib method
+        (or delFoo where the interface is named foo, etc).
+
+        The effect of deleting a stanza interface value named foo will be
+        one of:
+            1. Call delFoo, if it exists.
+            2. Delete foo element, if foo is in sub_interfaces.
+            3. Delete top level XML attribute named foo.
+            4. Remove the foo plugin, if it was loaded.
+            5. Do nothing.
+        """
+        if attrib in self.interfaces:
+            del_method = "del%s" % attrib.title()
+            if hasattr(self, del_method):
+                getattr(self, del_method)()
+            else:
+                if attrib in self.sub_interfaces:
+                    return self._delSub(attrib)
+                else:
+                    self._delAttr(attrib)
+        elif attrib in self.plugin_attrib_map:
+            if attrib in self.plugins:
+                del self.plugins[attrib]
+        return self
+
     @property
     def attrib(self): #backwards compatibility
             return self
@@ -352,20 +390,6 @@ class ElementBase(object):
     def findall(self, xpath):
             return self.xml.findall(xpath)
 
-    def __delitem__(self, attrib):
-            if attrib.lower() in self.interfaces:
-                    if hasattr(self, "del%s" % attrib.title()):
-                            getattr(self, "del%s" % attrib.title())()
-                    else:
-                            if attrib in self.sub_interfaces:
-                                    return self._delSub(attrib)
-                            else:
-                                    self._delAttr(attrib)
-            elif attrib in self.plugin_attrib_map:
-                    if attrib in self.plugins:
-                            del self.plugins[attrib]
-            return self
-
     def __eq__(self, other):
             if not isinstance(other, ElementBase):
                     return False

tests/test_elementbase.py

@@ -189,5 +189,46 @@ class TestElementBase(SleekTest):
           </foo>
         """)
 
+    def testDelItem(self):
+        """Test deleting stanza interface values."""
+
+        class TestStanza(ElementBase):
+            name = "foo"
+            namespace = "foo"
+            interfaces = set(('bar', 'baz', 'qux'))
+            sub_interfaces = set(('bar',))
+
+            def delQux(self):
+                pass
+
+        class TestStanzaPlugin(ElementBase):
+            name = "foobar"
+            namespace = "foo"
+            plugin_attrib = "foobar"
+            interfaces = set(('foobar',))
+
+        registerStanzaPlugin(TestStanza, TestStanzaPlugin)
+
+        stanza = TestStanza()
+        stanza['bar'] = 'a'
+        stanza['baz'] = 'b'
+        stanza['qux'] = 'c'
+        stanza['foobar']['foobar'] = 'd'
+
+        self.checkStanza(TestStanza, stanza, """
+          <foo xmlns="foo" baz="b" qux="c">
+            <bar>a</bar>
+            <foobar foobar="d" />
+          </foo>
+        """)
+
+        del stanza['bar']
+        del stanza['baz']
+        del stanza['qux']
+        del stanza['foobar']
+
+        self.checkStanza(TestStanza, stanza, """
+          <foo xmlns="foo" qux="c" />
+        """)
 
 suite = unittest.TestLoader().loadTestsFromTestCase(TestElementBase)