Fix #166, making sure we always cast raw tag override values to string (#188)

Author: thibaudcolas

Diff for: pattern_library/monkey_utils.py

@@ -73,8 +73,9 @@ def node_render(context):
                         context[target_var] = result
                         return ""
 
-                    # Render result instead of the tag
-                    return result
+                    # Render result instead of the tag, as a string.
+                    # See https://github.com/torchbox/django-pattern-library/issues/166.
+                    return str(result)
                 elif default_html is not UNSPECIFIED:
                     # Render provided default;
                     # if no stub data supplied.

Diff for: tests/templates/patterns/atoms/tags_test_atom/tags_test_atom.yaml

@@ -3,9 +3,9 @@ tags:
     empty_string:
       raw: ''
     none:
-      raw: 'None'
+      raw: None
     zero:
-      raw: '0'
+      raw: 0
   default_html_tag:
     page.url:
       raw: "example"
@@ -16,7 +16,6 @@ tags:
     empty_string:
       raw: ''
     none:
-      raw: 'None'
+      raw: None
     zero:
-      raw: '0'
-  
+      raw: 0