_process_desired_zone after populate, test/enforce order

octodns/provider/base.py

@@ -168,13 +168,6 @@ class BaseProvider(BaseSource):
     def plan(self, desired, processors=[]):
         self.log.info('plan: desired=%s', desired.name)
 
-        # Make a (shallow) copy of the desired state so that everything from
-        # now on (in this target) can modify it as they see fit without
-        # worrying about impacting other targets.
-        desired = desired.copy()
-
-        desired = self._process_desired_zone(desired)
-
         existing = Zone(desired.name, desired.sub_zones)
         exists = self.populate(existing, target=True, lenient=True)
         if exists is None:
@@ -183,6 +176,13 @@ class BaseProvider(BaseSource):
             self.log.warning('Provider %s used in target mode did not return '
                              'exists', self.id)
 
+        # Make a (shallow) copy of the desired state so that everything from
+        # now on (in this target) can modify it as they see fit without
+        # worrying about impacting other targets.
+        desired = desired.copy()
+
+        desired = self._process_desired_zone(desired)
+
         existing = self._process_existing_zone(existing)
 
         for processor in processors:

tests/test_octodns_provider_base.py

@@ -277,6 +277,37 @@ class TestBaseProvider(TestCase):
         # We filtered out the only change
         self.assertFalse(plan)
 
+    def test_plan_order_of_operations(self):
+
+        class MockProvider(BaseProvider):
+            log = getLogger('mock-provider')
+            SUPPORTS = set(('A',))
+            SUPPORTS_GEO = False
+
+            def __init__(self):
+                super().__init__('mock-provider')
+                self.calls = []
+
+            def populate(self, *args, **kwargs):
+                self.calls.append('populate')
+
+            def _process_desired_zone(self, *args, **kwargs):
+                self.calls.append('_process_desired_zone')
+                return super()._process_desired_zone(*args, **kwargs)
+
+            def _process_existing_zone(self, *args, **kwargs):
+                self.calls.append('_process_existing_zone')
+                return super()._process_existing_zone(*args, **kwargs)
+
+        provider = MockProvider()
+
+        zone = Zone('unit.tests.', [])
+        self.assertFalse(provider.plan(zone))
+        # ensure the calls were made in the expected order, populate comes
+        # first, then desired, then existing
+        self.assertEqual(['populate', '_process_desired_zone',
+                          '_process_existing_zone'], provider.calls)
+
     def test_process_desired_zone(self):
         provider = HelperProvider('test')