Move % addition to lookups, refactor postgres lookups.

These refactorings making overriding some text based lookup names on
other fields (specifically `contains`) much cleaner. It also removes a
bunch of duplication in the contrib.postgres lookups.

1 files changed, 32 insertions, 6 deletions

diff --git a/django/contrib/postgres/lookups.py b/django/contrib/postgres/lookups.py
index 4cf51dbd9c..eb7cfd8359 100644
--- a/django/contrib/postgres/lookups.py
+++ b/django/contrib/postgres/lookups.py
@@ -1,10 +1,36 @@
-from django.db.models import Transform
+from django.db.models import Lookup, Transform
 
 
-class Unaccent(Transform):
+class PostgresSimpleLookup(Lookup):
+    def as_sql(self, qn, connection):
+        lhs, lhs_params = self.process_lhs(qn, connection)
+        rhs, rhs_params = self.process_rhs(qn, connection)
+        params = lhs_params + rhs_params
+        return '%s %s %s' % (lhs, self.operator, rhs), params
+
+
+class FunctionTransform(Transform):
+    def as_sql(self, qn, connection):
+        lhs, params = qn.compile(self.lhs)
+        return "%s(%s)" % (self.function, lhs), params
+
+
+class DataContains(PostgresSimpleLookup):
+    lookup_name = 'contains'
+    operator = '@>'
+
+
+class ContainedBy(PostgresSimpleLookup):
+    lookup_name = 'contained_by'
+    operator = '<@'
+
+
+class Overlap(PostgresSimpleLookup):
+    lookup_name = 'overlap'
+    operator = '&&'
+
+
+class Unaccent(FunctionTransform):
     bilateral = True
     lookup_name = 'unaccent'
-
-    def as_postgresql(self, compiler, connection):
-        lhs, params = compiler.compile(self.lhs)
-        return "UNACCENT(%s)" % lhs, params
+    function = 'UNACCENT'