100% coverage for Length.

#Rename test module to match 'test_<MUT>' pattern.

BTrees/Length.py

@@ -28,8 +28,9 @@ class Length(persistent.Persistent):
     longer works as expected, because new-style classes cache
     class-defined slot methods (like __len__) in C type slots.  Thus,
     instance-defined slot fillers are ignored.
-
     """
+    # class-level default required to keep copy.deepcopy happy -- see
+    # https://bugs.launchpad.net/zodb/+bug/516653
     value = 0
 
     def __init__(self, v=0):

BTrees/tests/testLength.py → BTrees/tests/test_Length.py

@@ -11,40 +11,71 @@
 # FOR A PARTICULAR PURPOSE
 #
 ##############################################################################
-"""\
-Test for BTrees.Length module.
-
-"""
-__docformat__ = "reStructuredText"
-
-import BTrees.Length
-import copy
-import sys
 import unittest
 
 
+_marker = object()
+
 class LengthTestCase(unittest.TestCase):
 
-    def test_length_overflows_to_long(self):
-        length = BTrees.Length.Length(sys.maxint)
+    def _getTargetClass(self):
+        from BTrees.Length import Length
+        return Length
+
+    def _makeOne(self, value=_marker):
+        if value is _marker:
+            return self._getTargetClass()()
+        return self._getTargetClass()(value)
+
+    def test_ctor_default(self):
+        length = self._makeOne()
+        self.assertEqual(length.value, 0)
+
+    def test_ctor_explict(self):
+        length = self._makeOne(42)
+        self.assertEqual(length.value, 42)
+
+    def test___getstate___(self):
+        length = self._makeOne(42)
+        self.assertEqual(length.__getstate__(), 42)
+
+    def test___setstate__(self):
+        length = self._makeOne()
+        length.__setstate__(42)
+        self.assertEqual(length.value, 42)
+
+    def test_set(self):
+        length = self._makeOne()
+        length.set(42)
+        self.assertEqual(length.value, 42)
+
+    def test__p_resolveConflict(self):
+        length = self._makeOne()
+        self.assertEqual(length._p_resolveConflict(5, 7, 9), 11)
+
+    def test_change_overflows_to_long(self):
+        import sys
+        length = self._makeOne(sys.maxint)
         self.assertEqual(length(), sys.maxint)
         self.assert_(type(length()) is int)
         length.change(+1)
         self.assertEqual(length(), sys.maxint + 1)
         self.assert_(type(length()) is long)
 
-    def test_length_underflows_to_long(self):
+    def test_change_underflows_to_long(self):
+        import sys
         minint = (-sys.maxint) - 1
-        length = BTrees.Length.Length(minint)
+        length = self._makeOne(minint)
         self.assertEqual(length(), minint)
         self.assert_(type(length()) is int)
         length.change(-1)
         self.assertEqual(length(), minint - 1)
         self.assert_(type(length()) is long)
 
-    def test_copy(self):
+    def test_lp_516653(self):
         # Test for https://bugs.launchpad.net/zodb/+bug/516653
-        length = BTrees.Length.Length()
+        import copy
+        length = self._makeOne()
         other = copy.copy(length)
         self.assertEqual(other(), 0)