[property] Refactor merge strict policy

Author: mpsonntag

odml/property.py

@@ -376,42 +376,49 @@ def clone(self):
     def merge_check(self, source, strict=True):
         """
         Checks whether a source Property can be merged with self as destination and
-        raises a ValueError if any of the attributes definition, uncertainty, reference
-        or value_origin and potentially dtype differ in source and destination.
+        raises a ValueError if the values of source and destination are not compatible.
+        With parameter *strict=True* a ValueError is also raised, if any of the
+        attributes unit, definition, uncertainty, reference or value_origin and dtype
+        differ in source and destination.
 
         :param source: an odML Property.
-        :param strict: If strict is True the dtypes of self and other must be identical.
+        :param strict: If True, the attributes dtype, unit, uncertainty, definition,
+                       reference and value_origin of source and destination
+                       must be identical.
         """
         if not isinstance(source, BaseProperty):
             raise ValueError("odml.Property.merge: odML Property required.")
 
-        if strict and self.dtype != source.dtype:
+        # Catch unmerge-able values at this point to avoid
+        # failing Section tree merges which cannot easily be rolled back.
+        new_value = self._convert_value_input(source.value)
+        if not self._validate_values(new_value):
+            raise ValueError("odml.Property.merge: passed value(s) cannot "
+                             "be converted to data type '%s'!" % self._dtype)
+        if not strict:
+            return
+
+        if (self.dtype is not None and source.dtype is not None and
+                self.dtype != source.dtype):
             raise ValueError("odml.Property.merge: src and dest dtypes do not match!")
-        else:
-            # Catch unmerge-able values also at this point to avoid
-            # failing Section tree merges which cannot easily be rolled back.
-            new_value = self._convert_value_input(source.value)
-            if not self._validate_values(new_value):
-                raise ValueError("odml.Property.merge: passed value(s) cannot "
-                                 "be converted to data type '%s'!" % self._dtype)
 
         if self.unit is not None and source.unit is not None and self.unit != source.unit:
             raise ValueError("odml.Property.merge: "
                              "src and dest units (%s, %s) do not match!" %
                              (source.unit, self.unit))
 
+        if (self.uncertainty is not None and source.uncertainty is not None and
+                self.uncertainty != source.uncertainty):
+            raise ValueError("odml.Property.merge: "
+                             "src and dest uncertainty both set and do not match!")
+
         if self.definition is not None and source.definition is not None:
             self_def = ''.join(map(str.strip, self.definition.split())).lower()
             other_def = ''.join(map(str.strip, source.definition.split())).lower()
             if self_def != other_def:
                 raise ValueError("odml.Property.merge: "
                                  "src and dest definitions do not match!")
 
-        if (self.uncertainty is not None and source.uncertainty is not None and
-                self.uncertainty != source.uncertainty):
-            raise ValueError("odml.Property.merge: "
-                             "src and dest uncertainty both set and do not match!")
-
         if self.reference is not None and source.reference is not None:
             self_ref = ''.join(map(str.strip, self.reference.lower().split()))
             other_ref = ''.join(map(str.strip, source.reference.lower().split()))

test/test_property.py

@@ -435,85 +435,87 @@ def test_merge_check(self):
         source = Property(name="source", dtype="string")
         destination = Property(name="destination", dtype="string")
 
-        destination.merge_check(source, True)
+        destination.merge_check(source)
         source.dtype = "int"
         with self.assertRaises(ValueError):
-            destination.merge_check(source, True)
+            destination.merge_check(source)
+
         destination.merge_check(source, False)
 
         # Test value check
         source = Property(name="source", value=[1, 2, 3])
         destination = Property(name="destination", value=[4, 5, 6])
-        destination.merge_check(source, True)
+        destination.merge_check(source)
 
         # Test value convertable
         source = Property(name="source", value=["7", "8"])
         with self.assertRaises(ValueError):
-            destination.merge_check(source, True)
+            destination.merge_check(source)
+
         destination.merge_check(source, False)
 
         # Test value not convertable
         source = Property(name="source", value=["nine", "ten"])
         with self.assertRaises(ValueError):
-            destination.merge_check(source, True)
+            destination.merge_check(source)
         with self.assertRaises(ValueError):
             destination.merge_check(source, False)
 
         # Test unit check
         source = Property(name="source", unit="Hz")
         destination = Property(name="destination", unit="Hz")
 
-        destination.merge_check(source, True)
+        destination.merge_check(source)
         source.unit = "s"
         with self.assertRaises(ValueError):
-            destination.merge_check(source, True)
-        with self.assertRaises(ValueError):
-            destination.merge_check(source, False)
+            destination.merge_check(source)
+
+        destination.merge_check(source, False)
 
         # Test uncertainty check
         source = Property(name="source", uncertainty=0.0)
         destination = Property(name="destination", uncertainty=0.0)
 
-        destination.merge_check(source, True)
+        destination.merge_check(source)
         source.uncertainty = 10.0
         with self.assertRaises(ValueError):
-            destination.merge_check(source, True)
-        with self.assertRaises(ValueError):
-            destination.merge_check(source, False)
+            destination.merge_check(source)
+
+        destination.merge_check(source, False)
 
         # Test definition check
         source = Property(name="source", definition="Freude\t schoener\nGoetterfunken\n")
         destination = Property(name="destination",
                                definition="FREUDE schoener GOETTERfunken")
 
-        destination.merge_check(source, True)
+        destination.merge_check(source)
         source.definition = "Freunde schoender Goetterfunken"
         with self.assertRaises(ValueError):
-            destination.merge_check(source, True)
-        with self.assertRaises(ValueError):
-            destination.merge_check(source, False)
+            destination.merge_check(source)
+
+        destination.merge_check(source, False)
 
         # Test reference check
         source = Property(name="source", reference="portal.g-node.org")
         destination = Property(name="destination", reference="portal.g-node.org")
 
-        destination.merge_check(source, True)
+        destination.merge_check(source)
         source.reference = "portal.g-node.org/odml/terminologies/v1.1"
         with self.assertRaises(ValueError):
-            destination.merge_check(source, True)
-        with self.assertRaises(ValueError):
-            destination.merge_check(source, False)
+            destination.merge_check(source)
+
+        destination.merge_check(source, False)
 
         # Test value origin check
         source = Property(name="source", value_origin="file")
         destination = Property(name="destination", value_origin="file")
 
-        destination.merge_check(source, True)
+        destination.merge_check(source)
         source.value_origin = "other file"
         with self.assertRaises(ValueError):
-            destination.merge_check(source, True)
-        with self.assertRaises(ValueError):
-            destination.merge_check(source, False)
+            destination.merge_check(source)
+
+        destination.merge_check(source, False)
 
     def test_merge(self):
         p_dst = Property("p1", value=[1, 2, 3], unit="Hz", definition="Freude\t schoener\nGoetterfunken\n",