opc: add OpcPackage.core_properties

Also, organize fixture components separate from fixtures.

Author: Steve Canny

docx/opc/package.py

@@ -41,7 +41,7 @@ def core_properties(self):
         |CoreProperties| object providing read/write access to the Dublin
         Core properties for this document.
         """
-        raise NotImplementedError
+        return self._core_properties_part.core_properties
 
     def iter_rels(self):
         """
@@ -159,6 +159,14 @@ def save(self, pkg_file):
             part.before_marshal()
         PackageWriter.write(pkg_file, self.rels, self.parts)
 
+    @property
+    def _core_properties_part(self):
+        """
+        |CorePropertiesPart| object related to this package. Creates
+        a default core properties part if one is not present (not common).
+        """
+        raise NotImplementedError
+
 
 class Part(object):
     """

docx/opc/parts/__init__.py

@@ -0,0 +1,25 @@
+# encoding: utf-8
+
+"""
+Core properties part, corresponds to ``/docProps/core.xml`` part in package.
+"""
+
+from __future__ import (
+    absolute_import, division, print_function, unicode_literals
+)
+
+from ..package import XmlPart
+
+
+class CorePropertiesPart(XmlPart):
+    """
+    Corresponds to part named ``/docProps/core.xml``, containing the core
+    document properties for this document package.
+    """
+    @property
+    def core_properties(self):
+        """
+        A |CoreProperties| object providing read/write access to the core
+        properties contained in this core properties part.
+        """
+        raise NotImplementedError

docx/opc/parts/coreprops.py

@@ -8,19 +8,22 @@
 
 import pytest
 
+from docx.opc.coreprops import CoreProperties
 from docx.opc.oxml import CT_Relationships
 from docx.opc.packuri import PACKAGE_URI, PackURI
 from docx.opc.package import (
     OpcPackage, Part, PartFactory, _Relationship, Relationships,
     Unmarshaller, XmlPart
 )
+from docx.opc.parts.coreprops import CorePropertiesPart
 from docx.opc.pkgreader import PackageReader
 from docx.oxml.xmlchemy import BaseOxmlElement
 
 from ..unitutil.cxml import element
 from ..unitutil.mock import (
     call, class_mock, cls_attr_mock, function_mock, initializer_mock,
-    instance_mock, loose_mock, method_mock, Mock, patch, PropertyMock
+    instance_mock, loose_mock, method_mock, Mock, patch, PropertyMock,
+    property_mock
 )
 
 
@@ -113,8 +116,53 @@ def it_can_save_to_a_pkg_file(
             pkg_file_, pkg._rels, parts_
         )
 
+    def it_provides_access_to_the_core_properties(self, core_props_fixture):
+        opc_package, core_properties_ = core_props_fixture
+        core_properties = opc_package.core_properties
+        assert core_properties is core_properties_
+
     # fixtures ---------------------------------------------
 
+    @pytest.fixture
+    def core_props_fixture(
+            self, _core_properties_part_prop_, core_properties_part_,
+            core_properties_):
+        opc_package = OpcPackage()
+        _core_properties_part_prop_.return_value = core_properties_part_
+        core_properties_part_.core_properties = core_properties_
+        return opc_package, core_properties_
+
+    @pytest.fixture
+    def relate_to_part_fixture_(self, request, pkg, rels_, reltype):
+        rId = 'rId99'
+        rel_ = instance_mock(request, _Relationship, name='rel_', rId=rId)
+        rels_.get_or_add.return_value = rel_
+        pkg._rels = rels_
+        part_ = instance_mock(request, Part, name='part_')
+        return pkg, part_, reltype, rId
+
+    @pytest.fixture
+    def related_part_fixture_(self, request, rels_, reltype):
+        related_part_ = instance_mock(request, Part, name='related_part_')
+        rels_.part_with_reltype.return_value = related_part_
+        pkg = OpcPackage()
+        pkg._rels = rels_
+        return pkg, reltype, related_part_
+
+    # fixture components -----------------------------------
+
+    @pytest.fixture
+    def core_properties_(self, request):
+        return instance_mock(request, CoreProperties)
+
+    @pytest.fixture
+    def core_properties_part_(self, request):
+        return instance_mock(request, CorePropertiesPart)
+
+    @pytest.fixture
+    def _core_properties_part_prop_(self, request):
+        return property_mock(request, OpcPackage, '_core_properties_part')
+
     @pytest.fixture
     def PackageReader_(self, request):
         return class_mock(request, 'docx.opc.package.PackageReader')
@@ -171,23 +219,6 @@ def rel_attrs_(self, request):
         rId = 'rId99'
         return reltype, target_, rId
 
-    @pytest.fixture
-    def relate_to_part_fixture_(self, request, pkg, rels_, reltype):
-        rId = 'rId99'
-        rel_ = instance_mock(request, _Relationship, name='rel_', rId=rId)
-        rels_.get_or_add.return_value = rel_
-        pkg._rels = rels_
-        part_ = instance_mock(request, Part, name='part_')
-        return pkg, part_, reltype, rId
-
-    @pytest.fixture
-    def related_part_fixture_(self, request, rels_, reltype):
-        related_part_ = instance_mock(request, Part, name='related_part_')
-        rels_.part_with_reltype.return_value = related_part_
-        pkg = OpcPackage()
-        pkg._rels = rels_
-        return pkg, reltype, related_part_
-
     @pytest.fixture
     def rels_(self, request):
         return instance_mock(request, Relationships)