[1.8.x] Fixed #24833 -- Fixed Case expressions with exclude().

2 files changed, 24 insertions, 8 deletions

diff --git a/django/db/models/query_utils.py b/django/db/models/query_utils.py
index eca060e667..16496b7fad 100644
--- a/django/db/models/query_utils.py
+++ b/django/db/models/query_utils.py
@@ -263,3 +263,17 @@ def refs_aggregate(lookup_parts, aggregates):
         if level_n_lookup in aggregates and aggregates[level_n_lookup].contains_aggregate:
             return aggregates[level_n_lookup], lookup_parts[n:]
     return False, ()
+
+
+def refs_expression(lookup_parts, annotations):
+    """
+    A helper method to check if the lookup_parts contains references
+    to the given annotations set. Because the LOOKUP_SEP is contained in the
+    default annotation names we must check each prefix of the lookup_parts
+    for a match.
+    """
+    for n in range(len(lookup_parts) + 1):
+        level_n_lookup = LOOKUP_SEP.join(lookup_parts[0:n])
+        if level_n_lookup in annotations and annotations[level_n_lookup]:
+            return annotations[level_n_lookup], lookup_parts[n:]
+    return False, ()
diff --git a/django/db/models/sql/query.py b/django/db/models/sql/query.py
index 1a86266e6c..d0b56449b2 100644
--- a/django/db/models/sql/query.py
+++ b/django/db/models/sql/query.py
@@ -17,7 +17,9 @@ from django.db import DEFAULT_DB_ALIAS, connections
 from django.db.models.aggregates import Count
 from django.db.models.constants import LOOKUP_SEP
 from django.db.models.expressions import Col, Ref
-from django.db.models.query_utils import Q, PathInfo, refs_aggregate
+from django.db.models.query_utils import (
+    Q, PathInfo, refs_aggregate, refs_expression,
+)
 from django.db.models.sql.constants import (
     INNER, LOUTER, ORDER_DIR, ORDER_PATTERN, QUERY_TERMS, SINGLE,
 )
@@ -1027,9 +1029,9 @@ class Query(object):
         """
         lookup_splitted = lookup.split(LOOKUP_SEP)
         if self._annotations:
-            aggregate, aggregate_lookups = refs_aggregate(lookup_splitted, self.annotations)
-            if aggregate:
-                return aggregate_lookups, (), aggregate
+            expression, expression_lookups = refs_expression(lookup_splitted, self.annotations)
+            if expression:
+                return expression_lookups, (), expression
         _, field, _, lookup_parts = self.names_to_path(lookup_splitted, self.get_meta())
         field_parts = lookup_splitted[0:len(lookup_splitted) - len(lookup_parts)]
         if len(lookup_parts) == 0:
@@ -1144,7 +1146,7 @@ class Query(object):
         arg, value = filter_expr
         if not arg:
             raise FieldError("Cannot parse keyword query %r" % arg)
-        lookups, parts, reffed_aggregate = self.solve_lookup_type(arg)
+        lookups, parts, reffed_expression = self.solve_lookup_type(arg)
         if not allow_joins and len(parts) > 1:
             raise FieldError("Joined field references are not permitted in this query")
 
@@ -1153,12 +1155,12 @@ class Query(object):
         value, lookups, used_joins = self.prepare_lookup_value(value, lookups, can_reuse, allow_joins)
 
         clause = self.where_class()
-        if reffed_aggregate:
-            condition = self.build_lookup(lookups, reffed_aggregate, value)
+        if reffed_expression:
+            condition = self.build_lookup(lookups, reffed_expression, value)
             if not condition:
                 # Backwards compat for custom lookups
                 assert len(lookups) == 1
-                condition = (reffed_aggregate, lookups[0], value)
+                condition = (reffed_expression, lookups[0], value)
             clause.add(condition, AND)
             return clause, []