Change the default value of the 'extra' parameter in the 'create' met…

…hod of tagSAFEARRAY subtypes. (enthought#576)

* Changed the default value of the 'extra' parameter in the 'create' method
of tagSAFEARRAY subtypes which are generated by '_midlSAFEARRAY' to the
setting for 'extra' identified in the '_make_safearray_type' method.

The 'extra' value required for the creation of SAFEARRAYs with VT_RECORD,
VT_DISPATCH or VT_UNKNOWN elements is already identified at the time when
the associated tagSAFEARRAY subtype is created in the '_make_safearray_type'
method. Using this value by default for the 'extra' parameter when creating
an instance of the type does avoid performing the same identification process
again in user code.

* Added a unittest for the changed default value of the 'extra'
parameter in the 'create' method of tagSAFEARRAY subtypes.

* Changed the dispatch interface test to use the 'IDispSafearrayParamTest'
interface of the C++ COM test server instead of the 'IDictionary' interface
of the Microsoft Script Runtime.

* Removed unused import of 'ctypes.byref'.

Added values for the 'answer' and 'needs_clarification' fields of
the 'StructRecordParamTest' structure and included them in the
assertion testing.

comtypes/safearray.py

@@ -109,7 +109,7 @@ class _(object):
         _needsfree = False
 
         @classmethod
-        def create(cls, value, extra=None):
+        def create(cls, value, extra=extra):
             """Create a POINTER(SAFEARRAY_...) instance of the correct
             type; value is an object containing the items to store.
 

comtypes/test/test_midl_safearray_create.py

@@ -0,0 +1,100 @@
+# coding: utf-8
+
+from ctypes import c_int, pointer, POINTER
+import unittest
+
+import comtypes
+import comtypes.safearray
+from comtypes import CLSCTX_INPROC_SERVER, CLSCTX_LOCAL_SERVER
+from comtypes.client import CreateObject, GetModule
+import comtypes.typeinfo
+
+GetModule("UIAutomationCore.dll")
+from comtypes.gen.UIAutomationClient import CUIAutomation, IUIAutomation
+
+ComtypesCppTestSrvLib_GUID = "{07D2AEE5-1DF8-4D2C-953A-554ADFD25F99}"
+
+try:
+    GetModule((ComtypesCppTestSrvLib_GUID, 1, 0, 0))
+    from comtypes.gen.ComtypesCppTestSrvLib import StructRecordParamTest
+    from comtypes.gen.ComtypesCppTestSrvLib import IDispSafearrayParamTest
+
+    IMPORT_FAILED = False
+except (ImportError, OSError):
+    IMPORT_FAILED = True
+
+
+class Test_midlSAFEARRAY_create(unittest.TestCase):
+    def test_iunk(self):
+        extra = pointer(IUIAutomation._iid_)
+        iuia = CreateObject(
+            CUIAutomation().IPersist_GetClassID(),
+            interface=IUIAutomation,
+            clsctx=CLSCTX_INPROC_SERVER,
+        )
+        sa_type = comtypes.safearray._midlSAFEARRAY(POINTER(IUIAutomation))
+        for ptn, sa in [
+            ("with extra", sa_type.create([iuia], extra=extra)),
+            ("without extra", sa_type.create([iuia])),
+        ]:
+            with self.subTest(ptn=ptn):
+                (unpacked,) = sa.unpack()
+                self.assertIsInstance(unpacked, POINTER(IUIAutomation))
+
+    @unittest.skipIf(IMPORT_FAILED, "This depends on the out of process COM-server.")
+    def test_idisp(self):
+        extra = pointer(IDispSafearrayParamTest._iid_)
+        idisp = CreateObject(
+            "Comtypes.DispSafearrayParamTest",
+            clsctx=CLSCTX_LOCAL_SERVER,
+            interface=IDispSafearrayParamTest,
+        )
+        sa_type = comtypes.safearray._midlSAFEARRAY(POINTER(IDispSafearrayParamTest))
+        for ptn, sa in [
+            ("with extra", sa_type.create([idisp], extra=extra)),
+            ("without extra", sa_type.create([idisp])),
+        ]:
+            with self.subTest(ptn=ptn):
+                (unpacked,) = sa.unpack()
+                self.assertIsInstance(unpacked, POINTER(IDispSafearrayParamTest))
+
+    @unittest.skipIf(IMPORT_FAILED, "This depends on the out of process COM-server.")
+    def test_record(self):
+        extra = comtypes.typeinfo.GetRecordInfoFromGuids(
+            *StructRecordParamTest._recordinfo_
+        )
+        record = StructRecordParamTest()
+        record.question = "The meaning of life, the universe and everything?"
+        record.answer = 42
+        record.needs_clarification = True
+        sa_type = comtypes.safearray._midlSAFEARRAY(StructRecordParamTest)
+        for ptn, sa in [
+            ("with extra", sa_type.create([record], extra=extra)),
+            ("without extra", sa_type.create([record])),
+        ]:
+            with self.subTest(ptn=ptn):
+                (unpacked,) = sa.unpack()
+                self.assertIsInstance(unpacked, StructRecordParamTest)
+                self.assertEqual(
+                    unpacked.question,
+                    "The meaning of life, the universe and everything?",
+                )
+                self.assertEqual(unpacked.answer, 42)
+                self.assertEqual(unpacked.needs_clarification, True)
+
+    def test_ctype(self):
+        extra = None
+        cdata = c_int(1)
+        sa_type = comtypes.safearray._midlSAFEARRAY(c_int)
+        for ptn, sa in [
+            ("with extra", sa_type.create([cdata], extra=extra)),
+            ("without extra", sa_type.create([cdata])),
+        ]:
+            with self.subTest(ptn=ptn):
+                (unpacked,) = sa.unpack()
+                self.assertIsInstance(unpacked, int)
+                self.assertEqual(unpacked, 1)
+
+
+if __name__ == "__main__":
+    unittest.main()

source/CppTestSrv/SERVER.IDL

@@ -7,6 +7,8 @@
 
 import "oaidl.idl" ;
 
+// Simple structure used for tests related to IRecordInfo or GetRecordInfoFromGuids functionality.
+// If a new test would require other fields do NOT modify this structure but add a new structure instead.
 typedef [uuid(00FABB0F-5691-41A6-B7C1-11606671F8E5)]
 struct StructRecordParamTest {
 	BSTR question ;