Testing the template_context_prerender hook

This allows for modifying any context *right before render*, including
access to the variables that are passed in.  This test takes advantage
of that and takes one of the variables, "doubleme", and modifies
it (doubles it!)

In our case it turns "happy" and "joy" into "happyhappy" and "joyjoy".

This commit sponsored by Mark Holmquist.  Thank you!

mediagoblin/tests/testplugins/modify_context/__init__.py

@@ -26,6 +26,11 @@ def append_to_global_context(context):
     context['global_append'] = 'globally appended!'
     return context
 
+def double_doubleme(context):
+    if 'doubleme' in context:
+        context['doubleme'] = context['doubleme'] * 2
+    return context
+
 
 def setup_plugin():
     routes = [
@@ -46,4 +51,5 @@ hooks = {
     'setup': setup_plugin,
     ('modify_context.specific_page',
      'contextplugin/specific.html'): append_to_specific_context,
-    'template_global_context': append_to_global_context}
+    'template_global_context': append_to_global_context,
+    'template_context_prerender': double_doubleme}

mediagoblin/tests/testplugins/modify_context/templates/contextplugin/general.html

@@ -2,3 +2,4 @@ General page!
 
 global thing: {{ global_append }}
 lol: {{ lol }}
+doubleme: {{ doubleme }}

mediagoblin/tests/testplugins/modify_context/templates/contextplugin/specific.html

@@ -3,3 +3,4 @@ Specific page!
 specific thing: {{ specific_page_append }}
 global thing: {{ global_append }}
 something: {{ something }}
+doubleme: {{ doubleme }}

mediagoblin/tests/testplugins/modify_context/views.py

@@ -21,11 +21,13 @@ def specific(request):
     return render_to_response(
         request,
         'contextplugin/specific.html',
-        {"something": "orother"})
+        {"something": "orother",
+         "doubleme": "happy"})
 
 
 def general(request):
     return render_to_response(
         request,
         'contextplugin/general.html',
-        {"lol": "cats"})
+        {"lol": "cats",
+         "doubleme": "joy"})