Better empty value detection

libcomxml/core/__init__.py

@@ -96,7 +96,7 @@ def _parse_list(self, element, value):
         for val in value:
             if isinstance(val, XmlField):
                 val.parent = element.tag
-                self.parse_value(element, val)
+                self._parse_value(element, val)
             elif isinstance(val, XmlModel):
                 val.build_tree()
                 element.append(val.doc_root)
@@ -220,6 +220,13 @@ def __init__(self, name, root, drop_empty=True):
     def set_xml_encoding(self, encoding):
         self.xml_enc = encoding
 
+    def element_is_empty(self, element):
+        return (
+                (element.text is None or element.text.strip() == "") and
+                len(element) == 0 and
+                len(element.attrib) == 0
+        )
+
     def build_tree(self):
         """Bulids the tree with all the fields converted to Elements
         """
@@ -243,7 +250,7 @@ def build_tree(self):
                     for item in field:
                         if isinstance(item, XmlField):
                             ele = item.element()
-                            if self.drop_empty and len(ele) == 0:
+                            if self.drop_empty and self.element_is_empty(ele):
                                 continue
                             self.doc_root.append(ele)
                         elif isinstance(item, XmlModel):

tests/test_libcomxml.py

@@ -321,6 +321,52 @@ def __init__(self):
 
         self.assertXmlEqual(self.xml, str(l))
 
+class TestElementIsEmptyMethod(XMLTest):
+
+    def setUp(self):
+        self.xml_empty = "<LegalLiterals/>"
+
+        self.xml = "<LegalLiterals>"
+        self.xml += "<LegalReference>Demo Text</LegalReference>"
+        self.xml += "</LegalLiterals>"
+
+    def test_element_is_empty(self):
+
+        class LegalLiterals(XmlModel):
+            _sort_order = ('legalliterals', 'legalreference')
+
+            def __init__(self):
+                self.legalliterals = XmlField('LegalLiterals')
+                self.legalreference = []
+                super(LegalLiterals, self).__init__('LegalLiterals', 'legalliterals')
+
+        class LegalReference(XmlField):
+
+            def __init__(self, value=None):
+                super(LegalReference, self).__init__('LegalReference', value=value)
+
+        #There is no value inside legal literal: the legal reference is empty
+        legalliterals = LegalLiterals()
+        text = ''
+        legalreference = LegalReference(value=text)
+        legalliterals.legalreference = [legalreference]
+        is_empty = legalliterals.element_is_empty(legalliterals.legalreference[0].element())
+        self.assertTrue(is_empty)
+
+        legalliterals.build_tree()
+        self.assertXmlEqual(self.xml_empty, str(legalliterals))
+
+        #There is a value inside legal literal: the legal reference is not empty
+        legalliterals = LegalLiterals()
+        text = 'Demo Text'
+        legalreference = LegalReference(value=text)
+        legalliterals.legalreference = [legalreference]
+        is_empty = legalliterals.element_is_empty(legalliterals.legalreference[0].element())
+        self.assertFalse(is_empty)
+
+        legalliterals.build_tree()
+        self.assertXmlEqual(self.xml, str(legalliterals))
+
 
 class Namespaces(XMLTest):
     def setUp(self):