opc: refactor _ContentTypesItem interface

Steve Canny · Steve Canny · commit 2e158555cc91 · 2014-01-18T20:47:03.000-08:00
* change xml_for() to from_parts() constructor and return instance
instead of XML stream
* bring .blob property into _ContentTypesItem to return XML stream
diff --git a/docx/opc/pkgwriter.py b/docx/opc/pkgwriter.py
@@ -41,7 +41,8 @@ def _write_content_types_stream(phys_writer, parts):
         Write ``[Content_Types].xml`` part to the physical package with an
         appropriate content type lookup target for each part in *parts*.
         """
-        phys_writer.write(CONTENT_TYPES_URI, _ContentTypesItem.xml_for(parts))
+        cti = _ContentTypesItem.from_parts(parts)
+        phys_writer.write(CONTENT_TYPES_URI, cti.blob)
 
     @staticmethod
     def _write_parts(phys_writer, parts):
@@ -74,8 +75,16 @@ def __init__(self):
         self._defaults = CaseInsensitiveDict()
         self._overrides = dict()
 
+    @property
+    def blob(self):
+        """
+        Return XML form of this content types item, suitable for storage as
+        ``[Content_Types].xml`` in an OPC package.
+        """
+        return serialize_part_xml(self._element)
+
     @classmethod
-    def xml_for(cls, parts):
+    def from_parts(cls, parts):
         """
         Return content types XML mapping each part in *parts* to the
         appropriate content type and suitable for storage as
@@ -86,7 +95,7 @@ def xml_for(cls, parts):
         cti._defaults['.xml'] = CT.XML
         for part in parts:
             cti._add_content_type(part.partname, part.content_type)
-        return cti._xml()
+        return cti
 
     def _add_content_type(self, partname, content_type):
         """
@@ -99,7 +108,8 @@ def _add_content_type(self, partname, content_type):
         else:
             self._overrides[partname] = content_type
 
-    def _xml(self):
+    @property
+    def _element(self):
         """
         Return XML form of this content types item, suitable for storage as
         ``[Content_Types].xml`` in an OPC package. Although the sequence of
@@ -112,4 +122,4 @@ def _xml(self):
             _types_elm.add_default(ext, self._defaults[ext])
         for partname in sorted(self._overrides.keys()):
             _types_elm.add_override(partname, self._overrides[partname])
-        return serialize_part_xml(_types_elm)
+        return _types_elm
diff --git a/tests/opc/test_pkgwriter.py b/tests/opc/test_pkgwriter.py
@@ -9,14 +9,13 @@
 from mock import call, MagicMock, Mock, patch
 
 from docx.opc.constants import CONTENT_TYPE as CT
-from docx.opc.oxml import oxml_fromstring
 from docx.opc.package import Part
 from docx.opc.packuri import PackURI
 from docx.opc.phys_pkg import _ZipPkgWriter
 from docx.opc.pkgwriter import _ContentTypesItem, PackageWriter
 
 from .unitdata.types import a_Default, a_Types, an_Override
-from ..unitutil import instance_mock, method_mock
+from ..unitutil import class_mock, instance_mock, method_mock
 
 
 class DescribePackageWriter(object):
@@ -40,11 +39,13 @@ def it_can_write_a_package(self, PhysPkgWriter_, _write_methods):
         phys_writer.close.assert_called_once_with()
 
     def it_can_write_a_content_types_stream(self, write_cti_fixture):
-        phys_pkg_writer_, parts_, xml_for_ = write_cti_fixture
+        _ContentTypesItem_, parts_, phys_pkg_writer_, blob_ = (
+            write_cti_fixture
+        )
         PackageWriter._write_content_types_stream(phys_pkg_writer_, parts_)
-        xml_for_.assert_called_once_with(parts_)
+        _ContentTypesItem_.from_parts.assert_called_once_with(parts_)
         phys_pkg_writer_.write.assert_called_once_with(
-            '/[Content_Types].xml', xml_for_.return_value
+            '/[Content_Types].xml', blob_
         )
 
     def it_can_write_a_pkg_rels_item(self):
@@ -76,6 +77,22 @@ def it_can_write_a_list_of_parts(self):
 
     # fixtures ---------------------------------------------
 
+    @pytest.fixture
+    def blob_(self, request):
+        return instance_mock(request, str)
+
+    @pytest.fixture
+    def cti_(self, request, blob_):
+        return instance_mock(request, _ContentTypesItem, blob=blob_)
+
+    @pytest.fixture
+    def _ContentTypesItem_(self, request, cti_):
+        _ContentTypesItem_ = class_mock(
+            request, 'docx.opc.pkgwriter._ContentTypesItem'
+        )
+        _ContentTypesItem_.from_parts.return_value = cti_
+        return _ContentTypesItem_
+
     @pytest.fixture
     def parts_(self, request):
         return instance_mock(request, list)
@@ -91,8 +108,9 @@ def phys_pkg_writer_(self, request):
         return instance_mock(request, _ZipPkgWriter)
 
     @pytest.fixture
-    def write_cti_fixture(self, phys_pkg_writer_, parts_, xml_for_):
-        return phys_pkg_writer_, parts_, xml_for_
+    def write_cti_fixture(
+            self, _ContentTypesItem_, parts_, phys_pkg_writer_, blob_):
+        return _ContentTypesItem_, parts_, phys_pkg_writer_, blob_
 
     @pytest.fixture
     def _write_methods(self, request):
@@ -120,10 +138,9 @@ def xml_for_(self, request):
 
 class Describe_ContentTypesItem(object):
 
-    def it_can_compose_content_types_xml(self, xml_for_fixture):
-        parts, expected_xml = xml_for_fixture
-        types_xml = _ContentTypesItem.xml_for(parts)
-        types_elm = oxml_fromstring(types_xml)
+    def it_can_compose_content_types_element(self, xml_for_fixture):
+        cti, expected_xml = xml_for_fixture
+        types_elm = cti._element
         assert types_elm.xml == expected_xml
 
     # fixtures ---------------------------------------------
@@ -147,6 +164,7 @@ def _mock_part(self, request, name, partname_str, content_type):
     def xml_for_fixture(self, request):
         elm_type, partname_str, content_type = request.param
         part_ = self._mock_part(request, 'part_', partname_str, content_type)
+        cti = _ContentTypesItem.from_parts([part_])
         # expected_xml -----------------
         types_bldr = a_Types().with_nsdecls()
         ext = partname_str.split('.')[-1].lower()
@@ -171,4 +189,4 @@ def xml_for_fixture(self, request):
             types_bldr.with_child(override_bldr)
 
         expected_xml = types_bldr.xml()
-        return [part_], expected_xml
+        return cti, expected_xml
