Fix attribute access in async code.

CHANGES.rst

@@ -1,5 +1,14 @@
 .. currentmodule:: jinja2
 
+Version 2.11.1
+--------------
+
+Unreleased
+
+-   Fix a bug that prevented looking up a key after an attribute
+    (``{{ data.items[1:] }}``) in an async template. :issue:`1141`
+
+
 Version 2.11.0
 --------------
 

src/jinja2/compiler.py

@@ -1641,14 +1641,14 @@ def visit_Operand(self, node, frame):
     @optimizeconst
     def visit_Getattr(self, node, frame):
         if self.environment.is_async:
-            self.write("await auto_await(")
+            self.write("(await auto_await(")
 
         self.write("environment.getattr(")
         self.visit(node.node, frame)
         self.write(", %r)" % node.attr)
 
         if self.environment.is_async:
-            self.write(")")
+            self.write("))")
 
     @optimizeconst
     def visit_Getitem(self, node, frame):
@@ -1660,7 +1660,7 @@ def visit_Getitem(self, node, frame):
             self.write("]")
         else:
             if self.environment.is_async:
-                self.write("await auto_await(")
+                self.write("(await auto_await(")
 
             self.write("environment.getitem(")
             self.visit(node.node, frame)
@@ -1669,7 +1669,7 @@ def visit_Getitem(self, node, frame):
             self.write(")")
 
             if self.environment.is_async:
-                self.write(")")
+                self.write("))")
 
     def visit_Slice(self, node, frame):
         if node.start is not None:

tests/test_async.py

@@ -579,3 +579,7 @@ def test_nonrecursive_loop_filter(self, test_env_async):
     def test_bare_async(self, test_env_async):
         t = test_env_async.from_string('{% extends "header" %}')
         assert t.render(foo=42) == "[42|23]"
+
+    def test_awaitable_property_slicing(self, test_env_async):
+        t = test_env_async.from_string("{% for x in a.b[:1] %}{{ x }}{% endfor %}")
+        assert t.render(a=dict(b=[1, 2, 3])) == "1"