add PhysPkgWriter.__new__() factory method

Steve Canny · Steve Canny · commit 9bb9e5f8e421 · 2013-08-05T15:08:41.000-07:00
diff --git a/opc/phys_pkg.py b/opc/phys_pkg.py
@@ -26,6 +26,8 @@ class PhysPkgWriter(object):
     """
     Factory for physical package writer objects.
     """
+    def __new__(cls, pkg_file):
+        return ZipPkgWriter(pkg_file)
 
 
 class ZipPkgReader(object):
@@ -68,3 +70,9 @@ def rels_xml_for(self, source_uri):
         except KeyError:
             rels_xml = None
         return rels_xml
+
+
+class ZipPkgWriter(object):
+    """
+    Implements |PhysPkgWriter| interface for a zip file OPC package.
+    """
diff --git a/tests/test_phys_pkg.py b/tests/test_phys_pkg.py
@@ -12,7 +12,7 @@
 import hashlib
 
 from opc.packuri import PACKAGE_URI, PackURI
-from opc.phys_pkg import PhysPkgReader, ZipPkgReader
+from opc.phys_pkg import PhysPkgReader, PhysPkgWriter, ZipPkgReader
 
 import pytest
 
@@ -45,6 +45,22 @@ def it_constructs_a_pkg_reader_instance(self, ZipPkgReader_):
         assert phys_pkg_reader == ZipPkgReader_.return_value
 
 
+class DescribePhysPkgWriter(object):
+
+    @pytest.fixture
+    def ZipPkgWriter_(self, request):
+        return class_mock('opc.phys_pkg.ZipPkgWriter', request)
+
+    def it_constructs_a_pkg_writer_instance(self, ZipPkgWriter_):
+        # mockery ----------------------
+        pkg_file = Mock(name='pkg_file')
+        # exercise ---------------------
+        phys_pkg_writer = PhysPkgWriter(pkg_file)
+        # verify -----------------------
+        ZipPkgWriter_.assert_called_once_with(pkg_file)
+        assert phys_pkg_writer == ZipPkgWriter_.return_value
+
+
 class DescribeZipPkgReader(object):
 
     @pytest.fixture(scope='class')
