Fix #1647: Fix ARTICLE_ORDER_BY and add the ability to reverse order

ARTICLE_ORDER_BY wasn't doing anything because the ArticlesGenerator
was sorting articles after ARTICLE_ORDER_BY was applied. This fixes
that by adding the ability to reverse metadata order by adding the
option prefix 'reversed-' to metadata and changing the default value
to 'reversed-date'.

Relevant documentation is also updated and moved into a more appropriate
place ('Ordering Content' instead of 'URL settings').

pelican/generators.py

@@ -561,8 +561,7 @@ class ArticlesGenerator(CachingGenerator):
                     self.tags[tag].append(article)
             for author in getattr(article, 'authors', []):
                 self.authors[author].append(article)
-        # sort the articles by date
-        self.articles.sort(key=attrgetter('date'), reverse=True)
+
         self.dates = list(self.articles)
         self.dates.sort(key=attrgetter('date'),
                         reverse=self.context['NEWEST_FIRST_ARCHIVES'])

pelican/settings.py

@@ -65,7 +65,7 @@ DEFAULT_CONFIG = {
     'OUTPUT_RETENTION': [],
     'ARTICLE_URL': '{slug}.html',
     'ARTICLE_SAVE_AS': '{slug}.html',
-    'ARTICLE_ORDER_BY': 'slug',
+    'ARTICLE_ORDER_BY': 'reversed-date',
     'ARTICLE_LANG_URL': '{slug}-{lang}.html',
     'ARTICLE_LANG_SAVE_AS': '{slug}-{lang}.html',
     'DRAFT_URL': 'drafts/{slug}.html',

pelican/tests/test_generators.py

@@ -387,6 +387,65 @@ class TestArticlesGenerator(unittest.TestCase):
                                 'パイソン', 'マック'])
         self.assertEqual(tags, tags_expected)
 
+    def test_article_order_by(self):
+        settings = get_settings(filenames={})
+        settings['DEFAULT_CATEGORY'] = 'Default'
+        settings['DEFAULT_DATE'] = (1970, 1, 1)
+        settings['CACHE_CONTENT'] = False   # cache not needed for this logic tests
+        settings['ARTICLE_ORDER_BY'] = 'title'
+
+        generator = ArticlesGenerator(
+            context=settings.copy(), settings=settings,
+            path=CONTENT_DIR, theme=settings['THEME'], output_path=None)
+        generator.generate_context()
+
+        expected = [
+            'An Article With Code Block To Test Typogrify Ignore',
+            'Article title',
+            'Article with Nonconformant HTML meta tags',
+            'Article with markdown and summary metadata multi',
+            'Article with markdown and summary metadata single',
+            'Article with markdown containing footnotes',
+            'Article with template',
+            'Rst with filename metadata',
+            'Test Markdown extensions',
+            'Test markdown File',
+            'Test md File',
+            'Test mdown File',
+            'Test mkd File',
+            'This is a super article !',
+            'This is a super article !',
+            'This is a super article !',
+            'This is a super article !',
+            'This is a super article !',
+            'This is a super article !',
+            'This is an article with category !',
+            'This is an article with multiple authors in lastname, firstname format!',
+            'This is an article with multiple authors in list format!',
+            'This is an article with multiple authors!',
+            'This is an article with multiple authors!',
+            'This is an article without category !',
+            'This is an article without category !',
+            'マックOS X 10.8でパイソンとVirtualenvをインストールと設定']
+
+        articles = [article.title for article in generator.articles]
+        self.assertEqual(articles, expected)
+
+        # reversed title
+        settings = get_settings(filenames={})
+        settings['DEFAULT_CATEGORY'] = 'Default'
+        settings['DEFAULT_DATE'] = (1970, 1, 1)
+        settings['CACHE_CONTENT'] = False   # cache not needed for this logic tests
+        settings['ARTICLE_ORDER_BY'] = 'reversed-title'
+
+        generator = ArticlesGenerator(
+            context=settings.copy(), settings=settings,
+            path=CONTENT_DIR, theme=settings['THEME'], output_path=None)
+        generator.generate_context()
+
+        articles = [article.title for article in generator.articles]
+        self.assertEqual(articles, list(reversed(expected)))
+
 
 class TestPageGenerator(unittest.TestCase):
     # Note: Every time you want to test for a new field; Make sure the test
@@ -473,6 +532,23 @@ class TestPageGenerator(unittest.TestCase):
         pages = self.distill_pages(generator.pages)
         self.assertEqual(pages_expected_sorted_by_title, pages)
 
+        # sort by title reversed
+        pages_expected_sorted_by_title = [
+            ['This is a test page with a preset template', 'published',
+             'custom'],
+            ['This is a test page', 'published', 'page'],
+            ['This is a markdown test page', 'published', 'page'],
+            ['Page with a bunch of links', 'published', 'page'],
+            ['A Page (Test) for sorting', 'published', 'page'],
+        ]
+        settings['PAGE_ORDER_BY'] = 'reversed-title'
+        generator = PagesGenerator(
+            context=settings.copy(), settings=settings,
+            path=CUR_DIR, theme=settings['THEME'], output_path=None)
+        generator.generate_context()
+        pages = self.distill_pages(generator.pages)
+        self.assertEqual(pages_expected_sorted_by_title, pages)
+
     def test_tag_and_category_links_on_generated_pages(self):
         """
         Test to ensure links of the form {tag}tagname and {category}catname

pelican/utils.py

@@ -541,16 +541,28 @@ def process_translations(content_list, order_by=None):
             try:
                 index.sort(key=order_by)
             except Exception:
-                logger.error('Error sorting with function {}'.format(order_by))
-        elif order_by == 'basename':
-            index.sort(key=lambda x: os.path.basename(x.source_path or ''))
-        elif order_by != 'slug':
-            try:
-                index.sort(key=attrgetter(order_by))
-            except AttributeError:
-                error_msg = ('There is no "{}" attribute in the item metadata.'
-                             'Defaulting to slug order.')
-                logger.warning(error_msg.format(order_by))
+                logger.error('Error sorting with function %s', order_by)
+        elif isinstance(order_by, six.string_types):
+            if order_by.startswith('reversed-'):
+                order_reversed = True
+                order_by = order_by.replace('reversed-', '', 1)
+            else:
+                order_reversed = False
+
+            if order_by == 'basename':
+                index.sort(key=lambda x: os.path.basename(x.source_path or ''),
+                           reverse=order_reversed)
+            # already sorted by slug, no need to sort again
+            elif not (order_by == 'slug' and not order_reversed):
+                try:
+                    index.sort(key=attrgetter(order_by),
+                               reverse=order_reversed)
+                except AttributeError:
+                    logger.warning('There is no "%s" attribute in the item '
+                        'metadata. Defaulting to slug order.', order_by)
+        else:
+            logger.warning('Invalid *_ORDER_BY setting (%s).'
+                'Valid options are strings and functions.', order_by)
 
     return index, translations