Replace Path.not_exists() with Path.does_not_exist() (#335)

Author: jpinner-lyft

pynamodb/attributes.py

@@ -105,8 +105,8 @@ def is_in(self, *values):
     def exists(self):
         return AttributePath(self).exists()
 
-    def not_exists(self):
-        return AttributePath(self).not_exists()
+    def does_not_exist(self):
+        return AttributePath(self).does_not_exist()
 
     def is_type(self):
         # What makes sense here? Are we using this to check if deserialization will be successful?

pynamodb/constants.py

@@ -226,7 +226,7 @@
     GE: '__ge__',
     GT: '__gt__',
     NOT_NULL: 'exists',
-    NULL: 'not_exists',
+    NULL: 'does_not_exist',
     CONTAINS: 'contains',
     NOT_CONTAINS: 'contains',  # special cased
     BEGINS_WITH: 'startswith',

pynamodb/expressions/condition.py

@@ -105,7 +105,7 @@ def __getitem__(self, idx):
     def exists(self):
         return Exists(self)
 
-    def not_exists(self):
+    def does_not_exist(self):
         return NotExists(self)
 
     def is_type(self, attr_type):

pynamodb/tests/test_expressions.py

@@ -167,8 +167,8 @@ def test_exists(self):
         assert placeholder_names == {'foo': '#0'}
         assert expression_attribute_values == {}
 
-    def test_not_exists(self):
-        condition = self.attribute.not_exists()
+    def test_does_not_exist(self):
+        condition = self.attribute.does_not_exist()
         placeholder_names, expression_attribute_values = {}, {}
         expression = condition.serialize(placeholder_names, expression_attribute_values)
         assert expression == "attribute_not_exists (#0)"