From e89f8bae86518d9b3548b9744046817751336fa7 Mon Sep 17 00:00:00 2001
From: Matt Martz <matt@sivel.net>
Date: Wed, 10 Apr 2019 10:35:31 -0500
Subject: [PATCH] Extend jinja2 nested undefined support to keys/indices
 (#55094)

---
 .../jinja2_nested_undefined_getitem.yaml       |  2 ++
 lib/ansible/template/__init__.py               |  4 ++++
 .../targets/template/tasks/main.yml            | 18 ++++++++++++++++++
 3 files changed, 24 insertions(+)
 create mode 100644 changelogs/fragments/jinja2_nested_undefined_getitem.yaml

diff --git a/changelogs/fragments/jinja2_nested_undefined_getitem.yaml b/changelogs/fragments/jinja2_nested_undefined_getitem.yaml
new file mode 100644
index 0000000000..27c6865fbd
--- /dev/null
+++ b/changelogs/fragments/jinja2_nested_undefined_getitem.yaml
@@ -0,0 +1,2 @@
+minor_changes:
+- jinja2 - accesses to keys/indices on an undefined value now return further undefined values rather than throwing an exception
diff --git a/lib/ansible/template/__init__.py b/lib/ansible/template/__init__.py
index a3e6af1062..c5256c218c 100644
--- a/lib/ansible/template/__init__.py
+++ b/lib/ansible/template/__init__.py
@@ -207,6 +207,10 @@ class AnsibleUndefined(StrictUndefined):
         # Return original Undefined object to preserve the first failure context
         return self
 
+    def __getitem__(self, key):
+        # Return original Undefined object to preserve the first failure context
+        return self
+
     def __repr__(self):
         return 'AnsibleUndefined'
 
diff --git a/test/integration/targets/template/tasks/main.yml b/test/integration/targets/template/tasks/main.yml
index 64d08fe32c..6fd25e1095 100644
--- a/test/integration/targets/template/tasks/main.yml
+++ b/test/integration/targets/template/tasks/main.yml
@@ -666,6 +666,24 @@
       - list_var.0.foo.bar | default('DEFAULT') == 'DEFAULT'
       - list_var.1.foo is not defined
       - list_var.1.foo | default('DEFAULT') == 'DEFAULT'
+      - dict_var is defined
+      - dict_var['bar'] is defined
+      - dict_var['bar']['baz'] is not defined
+      - dict_var['bar']['baz'] | default('DEFAULT') == 'DEFAULT'
+      - dict_var['bar']['baz']['abc'] is not defined
+      - dict_var['bar']['baz']['abc'] | default('DEFAULT') == 'DEFAULT'
+      - dict_var['baz'] is not defined
+      - dict_var['baz']['abc'] is not defined
+      - dict_var['baz']['abc'] | default('DEFAULT') == 'DEFAULT'
+      - list_var[0] is defined
+      - list_var[1] is not defined
+      - list_var[0]['foo'] is defined
+      - list_var[0]['foo']['bar'] is not defined
+      - list_var[0]['foo']['bar'] | default('DEFAULT') == 'DEFAULT'
+      - list_var[1]['foo'] is not defined
+      - list_var[1]['foo'] | default('DEFAULT') == 'DEFAULT'
+      - dict_var['bar'].baz is not defined
+      - dict_var['bar'].baz | default('DEFAULT') == 'DEFAULT'
 
 - template:
     src: template_destpath_test.j2