pythoningLearning
diff --git a/‎opc/pkgreader.py‎
Lines changed: 19 additions & 0 deletions b/‎opc/pkgreader.py‎
Lines changed: 19 additions & 0 deletions
diff --git a/‎tests/test_pkgreader.py‎
Lines changed: 36 additions & 1 deletion b/‎tests/test_pkgreader.py‎
Lines changed: 36 additions & 1 deletion
@@ -12,6 +12,7 @@
 (OPC) package.
 """
 
+from opc.oxml import oxml_fromstring
 from opc.packuri import PACKAGE_URI
 from opc.phys_pkg import PhysPkgReader
 
@@ -116,15 +117,33 @@ def __init__(self, partname, content_type, blob, srels):
         super(_SerializedPart, self).__init__()
 
 
+class _SerializedRelationship(object):
+    """
+    Value object representing a serialized relationship in an OPC package.
+    Serialized, in this case, means any target part is referred to via its
+    partname rather than a direct link to an in-memory |Part| object.
+    """
+
+
 class _SerializedRelationshipCollection(object):
     """
     Read-only sequence of |_SerializedRelationship| instances corresponding
     to the relationships item XML passed to constructor.
     """
+    def __init__(self):
+        super(_SerializedRelationshipCollection, self).__init__()
+        self._srels = []
+
     @staticmethod
     def load_from_xml(baseURI, rels_item_xml):
         """
         Return |_SerializedRelationshipCollection| instance loaded with the
         relationships contained in *rels_item_xml*. Returns an empty
         collection if *rels_item_xml* is |None|.
         """
+        srels = _SerializedRelationshipCollection()
+        if rels_item_xml is not None:
+            rels_elm = oxml_fromstring(rels_item_xml)
+            for rel_elm in rels_elm.Relationship:
+                srels._srels.append(_SerializedRelationship(baseURI, rel_elm))
+        return srels
@@ -14,7 +14,9 @@
 from mock import call, Mock, patch
 
 from opc.phys_pkg import ZipPkgReader
-from opc.pkgreader import _ContentTypeMap, PackageReader
+from opc.pkgreader import (
+    _ContentTypeMap, PackageReader, _SerializedRelationshipCollection
+)
 
 from .unitutil import class_mock, initializer_mock, method_mock
 
@@ -175,3 +177,36 @@ def it_can_retrieve_srels_for_a_source_uri(
         phys_reader.rels_xml_for.assert_called_once_with(source_uri)
         load_from_xml.assert_called_once_with(source_uri.baseURI, rels_xml)
         assert retval == srels
+
+
+class Describe_SerializedRelationshipCollection(object):
+
+    @pytest.fixture
+    def oxml_fromstring(self, request):
+        _patch = patch('opc.pkgreader.oxml_fromstring')
+        request.addfinalizer(_patch.stop)
+        return _patch.start()
+
+    @pytest.fixture
+    def _SerializedRelationship_(self, request):
+        return class_mock('opc.pkgreader._SerializedRelationship', request)
+
+    def it_can_load_from_xml(self, oxml_fromstring, _SerializedRelationship_):
+        # mockery ----------------------
+        baseURI, rels_item_xml, rel_elm_1, rel_elm_2 = (
+            Mock(name='baseURI'), Mock(name='rels_item_xml'),
+            Mock(name='rel_elm_1'), Mock(name='rel_elm_2'),
+        )
+        rels_elm = Mock(name='rels_elm', Relationship=[rel_elm_1, rel_elm_2])
+        oxml_fromstring.return_value = rels_elm
+        # exercise ---------------------
+        srels = _SerializedRelationshipCollection.load_from_xml(
+            baseURI, rels_item_xml)
+        # verify -----------------------
+        expected_calls = [
+            call(baseURI, rel_elm_1),
+            call(baseURI, rel_elm_2),
+        ]
+        oxml_fromstring.assert_called_once_with(rels_item_xml)
+        assert _SerializedRelationship_.call_args_list == expected_calls
+        assert isinstance(srels, _SerializedRelationshipCollection)