Adding verbose option for more explicit output on get_dirty_fields, p…

…roposition for #59

src/dirtyfields/dirtyfields.py

@@ -54,7 +54,7 @@ def _as_dict(self, check_relationship):
 
         return all_field
 
-    def get_dirty_fields(self, check_relationship=False):
+    def get_dirty_fields(self, check_relationship=False, verbose=False):
         # check_relationship indicates whether we want to check for foreign keys
         # and one-to-one fields or ignore them
         new_state = self._as_dict(check_relationship)
@@ -64,7 +64,12 @@ def get_dirty_fields(self, check_relationship=False):
             original_value = self._original_state[key]
 
             is_identical = self.compare_function[0](value, original_value, **self.compare_function[1])
-            if not is_identical:
+            if is_identical:
+                continue
+
+            if verbose:
+                all_modify_field[key] = {'saved': original_value, 'current': value}
+            else:
                 all_modify_field[key] = original_value
 
         return all_modify_field

tests/test_core.py

@@ -127,3 +127,18 @@ def test_validationerror():
 
     tm.boolean = False
     assert tm.get_dirty_fields() == {'boolean': None}
+
+
+def test_verbose_mode():
+    tm = TestModel()
+
+    # initial state is dirty because it has not been saved yet in the db
+    assert tm.is_dirty()
+    assert tm.get_dirty_fields() == {}
+
+    # changing values should flag them as dirty
+    tm.boolean = False
+
+    assert tm.get_dirty_fields(verbose=True) == {
+        'boolean': {'saved': True, 'current': False}
+    }