Merge pull request #1059 from benjaoming/fix-checks-load-templatetags

Soften a check failure

docs/release_notes.rst

@@ -13,6 +13,15 @@ Release plan
 * **0.7.x** Milestone TBA
 
 
+0.6.1.dev
+---------
+
+Fixed
+~~~~~
+
+* Do not fail prematurely during Django checks framework (rare issue) :url-issue:`1059` (Benjamin Bach)
+
+
 0.6
 ---
 

src/wiki/checks.py

@@ -64,16 +64,29 @@ def check_for_obsolete_installed_apps(app_configs, **kwargs):
 
 def check_for_context_processors(app_configs, **kwargs):
     errors = []
-    context_processors = Engine.get_default().context_processors
-    for context_processor in REQUIRED_CONTEXT_PROCESSORS:
-        if context_processor[0] not in context_processors:
-            errors.append(
-                Error(
-                    "needs %s in TEMPLATE['OPTIONS']['context_processors']"
-                    % context_processor[0],
-                    id="wiki.%s" % context_processor[1],
+    # Pattern from django.contrib.admin.checks
+    try:
+        default_template_engine = Engine.get_default()
+    except Exception:
+        # Skip this non-critical check:
+        # 1. if the user has a non-trivial TEMPLATES setting and Django
+        #    can't find a default template engine
+        # 2. if anything goes wrong while loading template engines, in
+        #    order to avoid raising an exception from a confusing location
+        # Catching ImproperlyConfigured suffices for 1. but 2. requires
+        # catching all exceptions.
+        pass
+    else:
+        context_processors = default_template_engine.context_processors
+        for context_processor in REQUIRED_CONTEXT_PROCESSORS:
+            if context_processor[0] not in context_processors:
+                errors.append(
+                    Error(
+                        "needs %s in TEMPLATES[*]['OPTIONS']['context_processors']"
+                        % context_processor[0],
+                        id="wiki.%s" % context_processor[1],
+                    )
                 )
-            )
     return errors
 
 

tests/core/test_checks.py

@@ -38,7 +38,7 @@ def test_required_context_processors(self):
                 errors = registry.run_checks(tags=[Tags.context_processors])
                 expected_errors = [
                     Error(
-                        "needs %s in TEMPLATE['OPTIONS']['context_processors']"
+                        "needs %s in TEMPLATES[*]['OPTIONS']['context_processors']"
                         % context_processor[0],
                         id="wiki.%s" % context_processor[1],
                     )