From c205163fd7436e2fc42cbe52626425a88c2cbddc Mon Sep 17 00:00:00 2001
From: saagit <55336016+saagit@users.noreply.github.com>
Date: Thu, 27 Aug 2020 19:11:25 -0700
Subject: [PATCH] Fix compatibility with Pelican 4.5.0 when PLUGINS is not set
 in pelicanconf.py

Pelican 4.5.0 changed the plugins mechanism and the default for
PLUGINS is now None.  The following type of construct is used in a
number of places in Flex:

    {% if 'tipue_search' in PLUGINS %}

If PLUGINS is not set in pelicanconf.py, the following exception will
be triggered under Pelican 4.5.0:

    TypeError: argument of type 'NoneType' is not iterable

The Pelican maintainers did not intend the examination of PLUGINS by
templates to be a stable API (per a discussion on IRC).  Per their
request, an enhancement request for a mechanism to do this has been
submitted here: https://github.com/getpelican/pelican/issues/2797

This commit changes the problematic constructs in Flex to be in the
style of:

    {% if PLUGINS and 'tipue_search' in PLUGINS %}

This allows Flex to work with Pelican 4.5.0 even if users do not
define PLUGINS.  Note that to use the new namespace plugins in Pelican
4.5.0, PLUGINS will have to be left at its default of None.

Resolves #245
---
 templates/article.html           | 2 +-
 templates/base.html              | 6 +++---
 templates/index.html             | 2 +-
 templates/partial/neighbors.html | 2 +-
 templates/search.html            | 2 +-
 5 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/templates/article.html b/templates/article.html
index e4aaddd..44d3fe1 100644
--- a/templates/article.html
+++ b/templates/article.html
@@ -30,7 +30,7 @@
            when=article.locale_date,
            category='<a href="%s/%s">%s</a>'|format(SITEURL, article.category.url, article.category)|safe) }}
 
-      {% if 'post_stats' in PLUGINS %}
+      {% if PLUGINS and 'post_stats' in PLUGINS %}
         &#8226; {{ _('%(minutes)s min read', minutes=article.stats['read_mins']) }}
       {% endif %}
     </p>
diff --git a/templates/base.html b/templates/base.html
index b3f208f..10c5400 100644
--- a/templates/base.html
+++ b/templates/base.html
@@ -69,7 +69,7 @@
           href="{{ SITEURL }}/{{ THEME_STATIC_DIR }}/pygments/{{ PYGMENTS_STYLE|default('github') }}.min.css">
   {% endif %}
 
-  {% if 'tipue_search' in PLUGINS %}
+  {% if PLUGINS and 'tipue_search' in PLUGINS %}
     <script src="{{ SITEURL }}/{{ THEME_STATIC_DIR }}/tipuesearch/jquery.min.js"></script>
     <script src="{{ SITEURL }}/{{ THEME_STATIC_DIR }}/tipuesearch/tipuesearch.min.js"></script>
     <script src="{{ SITEURL }}/{{ THEME_STATIC_DIR }}/tipuesearch/tipuesearch.min.js"></script>
@@ -156,7 +156,7 @@
 
       {% if SITESUBTITLE %}<p>{{ SITESUBTITLE }}</p>{% endif %}
 
-      {% if 'tipue_search' in PLUGINS %}
+      {% if PLUGINS and 'tipue_search' in PLUGINS %}
         <form class="navbar-search" action="/search.html" role="search">
           <input type="text" name="q" id="tipue_search_input" placeholder="{{ _('Search...') }}">
         </form>
@@ -280,7 +280,7 @@
     {% include 'partial/github.html' %}
   {% endif %}
 
-  {% if 'tipue_search' in PLUGINS %}
+  {% if PLUGINS and 'tipue_search' in PLUGINS %}
     <script>
       $(document).ready(function() {
         $('#tipue_search_input').tipuesearch();
diff --git a/templates/index.html b/templates/index.html
index f61d79c..b38808b 100644
--- a/templates/index.html
+++ b/templates/index.html
@@ -28,7 +28,7 @@
           {% endfor %}
       {% endif %}
 
-      {% if 'post_stats' in PLUGINS %}
+      {% if PLUGINS and 'post_stats' in PLUGINS %}
         &#8226; {{ _('%(minutes)s min read', minutes=article.stats['read_mins']) }}
       {% endif %}
     </p>
diff --git a/templates/partial/neighbors.html b/templates/partial/neighbors.html
index 4c698b0..a03a9e1 100644
--- a/templates/partial/neighbors.html
+++ b/templates/partial/neighbors.html
@@ -1,4 +1,4 @@
-{% if 'neighbors' in PLUGINS %}
+{% if PLUGINS and 'neighbors' in PLUGINS %}
   <div class="neighbors">
   {% if article.prev_article %}
     <a class="btn float-left" href="{{ SITEURL }}/{{ article.prev_article.url }}" title="{{ article.prev_article.title|striptags }}">
diff --git a/templates/search.html b/templates/search.html
index df8c004..1252834 100644
--- a/templates/search.html
+++ b/templates/search.html
@@ -1,4 +1,4 @@
-{% if 'tipue_search' in PLUGINS %}
+{% if PLUGINS and 'tipue_search' in PLUGINS %}
 {% extends 'base.html' %}
 {% block title %}{{ _('Search') }} - {{ SITENAME|striptags }}{% endblock title %}
 {% block content %}