view: Show pagination ellipsis only when needed

Signed-off-by: Stephen Finucane <[email protected]>
Closes: getpatchwork#614

Author: stephenfin

patchwork/paginator.py

@@ -79,6 +79,18 @@ def __init__(self, request, objects):
             if n > 0 and n <= pages
         ]
 
+        self.show_leading_ellipsis = False
+        if self.leading_set and self.adjacent_set:
+            # prevent e.g. 1 2 ... 3 4 5 ... 8 9
+            if self.leading_set[-1] != self.adjacent_set[0] - 1:
+                self.show_leading_ellipsis = True
+
+        self.show_trailing_ellipsis = False
+        if self.trailing_set and self.adjacent_set:
+            # prevent e.g. 1 2 ... 5 6 7 ... 8 9
+            if self.trailing_set[0] != self.adjacent_set[-1] + 1:
+                self.show_trailing_ellipsis = True
+
         self.long_page = (
             len(self.current_page.object_list) >= LONG_PAGE_THRESHOLD
         )

patchwork/templates/patchwork/partials/pagination.html

@@ -10,10 +10,10 @@
   <span class="prev-na">&laquo;</span>
 {% endif %}
 
-{% if page.paginator.leading_set %}
 {% for p in page.paginator.leading_set %}
   <span class="page"><a href="{% listurl page=p %}" >{{ p }}</a></span>
 {% endfor %}
+{% if page.paginator.show_leading_ellipsis %}
   …
 {% endif %}
 
@@ -25,12 +25,12 @@
 {% endif %}
 {% endfor %}
 
-{% if page.paginator.trailing_set %}
+{% if page.paginator.show_trailing_ellipsis %}
   …
+{% endif %}
 {% for p in page.paginator.trailing_set %}
   <span class="page"><a href="{% listurl page=p %}">{{ p }}</a></span>
 {% endfor %}
-{% endif %}
 
 {% if page.has_next %}
   <span class="next">