Changeset 221

Timestamp:

07/11/06 18:01:29

Author:

dowski

Message:

Some decimal.Decimal related enhancements (see MC #305).

1. New storeado.float_from_com and decimal_from_com functions. These functions properly convert the CURRENCY tuples that can be returned by pythoncom.

2. storage/storeado.py can now handle decimal.Decimal objects returned by pythoncom for CURRENCY datatypes. This will be the default behavior of pythoncom in the future.

3. Tests for the new decimal handling functionality in storage/storeado.py. Tests storing and retrieving FixedPoint? and Decimal values 3 ways; with the values stored in the database as DOUBLES (standard), with values in the database stored as CURRENCY and recalled as tuples, and finally stored as CURRENCY and recalled as Decimals.

4. arenas.Arena.add_store can now accept a storage manager class as well as a class string or instance.

Files:

• trunk/arenas.py (modified) (2 diffs)
• trunk/storage/storeado.py (modified) (3 diffs)
• trunk/test/test_storemsaccess.py (modified) (2 diffs)

trunk/arenas.py

@@ -1 +1 @@
-
-import ConfigParser
+from types import ClassType
-
-from containers import Graph
@@ -70 +71 @@
-        if isinstance(store, basestring):
-            store = xray.classes(store)(name, self, options or {})
+
+        elif isinstance(store, (type, ClassType)):
+            store = store(name, self, options or {})
-        
-        self.stores[name] = store

trunk/storage/storeado.py

@@ -121 +121 @@
-    return datetime.time(hour, minute, second)
-
+def float_from_com(com_currency):
+    """Convert a value from a Currency field to a float value.
+
+    Courtesy of Alex Martelli from:
+    http://groups.google.com/group/comp.lang.python/browse_frm/thread/fed03c64735c9e9c
+    """
+    return float((long(com_currency[1])&0xFFFFFFFFL) |
+                 (long(com_currency[0]) << 32)) / 1e4
+
+def decimal_from_com(com_currency):
+    """Convert a value from a Currency field to a Decimal value."""
+    
+    return decimal.Decimal(str(float_from_com(com_currency)))
+
-
-class AdapterFromADO(db.AdapterFromDB):
@@ -163 +177 @@
-        # See coerce_datetime
-        return time_from_com(value)
+
+    def coerce_decimal_Decimal(self, value, coltype):
+        if coltype == 0x06:
+            # Currency
+            if isinstance(value, tuple):
+                value = decimal_from_com(value)
+        else:
+            value = decimal.Decimal(str(value))
+        return value.quantize(decimal.Decimal('.01'))
-    
-    def coerce_fixedpoint_FixedPoint(self, value, coltype):
-        if coltype == 0x06:
-            # Currency
-
+
+
-        return fixedpoint.FixedPoint(value)
-    
@@ -173 +197 @@
-        if coltype == 0x06:
-            # Currency
-
+
+
-        return float(value)
-    

trunk/test/test_storemsaccess.py

@@ -18 +18 @@
-                          "The MSAccess test will not be run.")
-    else:
+        
+        class CurrencyAdapter(storeado.FieldTypeAdapter_MSAccess):
+            """Stores Decimal and FixedPoint objects as CURRENCY."""
+            
+            def coerce_decimal_Decimal(self, cls, key):
+                return "CURRENCY"
+
+            def coerce_fixedpoint_FixedPoint(self, cls, key):
+                return "CURRENCY"
+            
-        SM_class = "dejavu.storage.storeado.StorageManagerADO_MSAccess"
-        opts = {u'Connect': "PROVIDER=MICROSOFT.JET.OLEDB.4.0;"
@@ -25 +35 @@
-        def run():
-            import zoo_fixture
+
+            # lists to keep track of the test_currency runs            
+            standard_runs = []
+            altered_runs = []
+            
+            def test_currency(obj):
+                sm = zoo_fixture.arena.stores['testSM']
+                fta = sm.typeAdapter.__class__.__name__
+                
+                clsnames = ('Exhibit', 'Zoo')
+                tblnames = [sm.table_name(cn).strip('[]') for cn in clsnames]
+                colnames = ('Acreage', 'Admission')
+                targets = dict(zip(tblnames, colnames))
+                data, _ = sm.fetch(storeado.adSchemaColumns, conn=None,
+                                   schema=True)
+                for row in data:
+                    match = targets.get(row[2])
+                    if not match:
+                        continue
+                    if match == row[3]:
+##                        print row[2], row[3], row[11]
+                        dt = row[11]
+
+                        if fta in ("CurrencyAdapter",):                    
+                            obj.assertEqual(dt, storeado.adCurrency)
+                        else:
+                            obj.assertEqual(dt, storeado.adDouble)
+                            obj.assertEqual(len(standard_runs), 0)
+                    
+                    
-            # Isolate schema changes from one test to the next.
-            reload(zoo_fixture)
+
+            # test the standard MS Access setup where Decimal and FixedPoint
+            # objects are stored in the database as INTEGERS, LONGS or DOUBLES
+            print
+            print "Standard MSAccess test."
+            zoo_fixture.ZooTests.test_currency = test_currency
-            zoo_fixture.init()
-            zoo_fixture.run(SM_class, opts)
+            standard_runs.append(True)
+
+            # plugin the adapter for testing CURRENCY columns
+            storeado.StorageManagerADO_MSAccess.typeAdapter = CurrencyAdapter()
+
+            reload(zoo_fixture)
+
+            # test storing and recalling Decimal values to the database using
+            # CURRENCY columns - the (current) default behavior of pythoncom
+            # is to return CURRENCY values as a tuple
+            print
+            print "MSAccess test - CURRENCY returned as tuple."
+            zoo_fixture.ZooTests.test_currency = test_currency
+            zoo_fixture.init()
+            zoo_fixture.run(SM_class, opts)
+            altered_runs.append(True)
+
+            # set pythoncom to return CURRENCY values as Decimal objects
+            pythoncom.__future_currency__ = True
+            
+            reload(zoo_fixture)
+
+            # test storing and recalling Decimal values to the database using
+            # CURRENCY columns - CURRENCY values are now returned as Decimal
+            # objects
+            print
+            print "MSAccess test - CURRENCY returned as Decimal."
+            zoo_fixture.ZooTests.test_currency = test_currency
+            zoo_fixture.init()
+            zoo_fixture.run(SM_class, opts)
+            altered_runs.append(True)
-
-if __name__ == "__main__":