Fix flake8 failures with newer flake8 versions

Author: jvperrin

ocfweb/component/markdown.py

@@ -12,15 +12,15 @@
 from ocfweb.caching import cache
 
 # tags of a format like: [[!meta title="Backups"]]
-META_REGEX = re.compile('\[\[!meta ([a-z]+)="([^"]*)"\]\]')
+META_REGEX = re.compile(r'\[\[!meta ([a-z]+)="([^"]*)"\]\]')
 
 
 class HtmlCommentsInlineLexerMixin:
     """Strip HTML comments inside lines."""
 
     def enable_html_comments(self):
         self.rules.html_comment = re.compile(
-            '^<!--(.*?)-->',
+            r'^<!--(.*?)-->',
         )
         self.default_rules.insert(0, 'html_comment')
 
@@ -33,7 +33,7 @@ class HtmlCommentsBlockLexerMixin:
 
     def enable_html_comments(self):
         self.rules.html_comment = re.compile(
-            '^<!--(.*?)-->',
+            r'^<!--(.*?)-->',
         )
         self.default_rules.insert(0, 'html_comment')
 
@@ -74,16 +74,16 @@ class DjangoLinkInlineLexerMixin:
         [[human readable name|doc staff/backend/backups#something]]
     """
 
-    split_words = re.compile('((?:\S|\\\\ )+)')
+    split_words = re.compile(r'((?:\S|\\ )+)')
 
     def enable_django_links(self):
         self.rules.django_link = re.compile(
-            '^\[\[(?!\!)'
-            '([\s\S]+?)'
-            '\|'
-            '([^#]+?)'
-            '(?:#(.*?))?'
-            '\]\]',
+            r'^\[\[(?!\!)'
+            r'([\s\S]+?)'
+            r'\|'
+            r'([^#]+?)'
+            r'(?:#(.*?))?'
+            r'\]\]',
         )
         self.default_rules.insert(0, 'django_link')
 
@@ -141,7 +141,7 @@ def header(self, text, level, raw=None):
         else:
             id = 'h{level}_{title}'.format(
                 level=level,
-                title=re.sub('[^a-z0-9\-_ ]', '', strip_tags(text).lower()).strip().replace(' ', '-'),
+                title=re.sub(r'[^a-z0-9\-_ ]', '', strip_tags(text).lower()).strip().replace(' ', '-'),
             )
 
             # dumb collision avoidance

ocfweb/docs/urls.py

@@ -57,7 +57,7 @@ def send_redirect(request, redir_src):
 def doc_name(doc_name):
     # we can't actually deal with escaping into a regex, so we just use a whitelist
     assert re.match(r'^/[a-zA-Z0-9\-/]+$', doc_name), 'Bad document name: ' + doc_name
-    return doc_name[1:].replace('-', '\-')
+    return doc_name[1:].replace('-', '\\-')
 
 
 doc_names = '|'.join(map(doc_name, DOCS.keys()))

ocfweb/main/hosting_logos.py

@@ -60,7 +60,7 @@ def hosting_logo(request, image):
     student group websites."""
     # legacy images
     if image in LEGACY_IMAGES:
-        return redirect('hosting-logo', re.sub('\.[a-z]+$', '.png', image), permanent=True)
+        return redirect('hosting-logo', re.sub(r'\.[a-z]+$', '.png', image), permanent=True)
     elif image in REPLACED_IMAGES:
         return redirect('hosting-logo', REPLACED_IMAGES[image], permanent=True)
 

tox.ini

@@ -1,7 +1,11 @@
 [flake8]
 max-line-length = 119
 # flake8 complains about 'redefinition' of imported pytest fixtures
-ignore = F811
+# W503/W504 contradict each other, so we choose one to stick with
+#
+# We can't use default-ignore, since we still want to check against some of the
+# error checks that are ignored by default
+ignore = F811, W504
 
 [pep8]
 # autopep8 will rewrite lines to be shorter, even though we raised the length