Merged in [14374] from kivinen@iki.fi:

    If draft name has rfcXXXX-bis or rfcXXXXbis then add rfcXXXX to diff context menu. Fixes ietf-tools#460 (7 years old ticket).
 - Legacy-Id: 14375
Note: SVN reference [14374] has been migrated to Git commit 23d053e

Author: levkowetz

PLAN

@@ -43,6 +43,11 @@ Planned work in rough order
 * Transition to Python 3.  This will make it easier to add add support for
   internationalsed email, and also other i18n enhancements.
 
+* Update IPR disclosure pages with 1) itemized section V, 2) use the RFC
+  Updates and Obsoletes fields to add document relationships to be followed by
+  IPR searches, 3) show current values in the IPR update form, and 4) show
+  updates in a diff format (old/new columns).
+
 * Add support for document shepherding reports, possibly re-using or
   generalising some of the review plumbing.  Check with IESG for details.
 

ietf/doc/templatetags/ietf_filters.py

@@ -536,3 +536,8 @@ def role_names(roles):
 @register.filter()
 def zaptmp(s):
     return re.sub(r'/tmp/tmp[^/]+/', '', s)
+
+@register.filter()
+def rfcbis(s):
+    m = re.search('^.*-rfc(\d+)-?bis(-.*)?$', s)
+    return None if m is None else 'rfc' + m.group(1) 

ietf/templates/doc/document_history.html

@@ -36,6 +36,11 @@ <h2>Revision differences</h2>
 	        ({{ time|date:"Y-m-d" }})
 	      </option>
 	    {% endfor %}
+	    {% if doc.name|rfcbis %}
+	      <option value="{{ doc.name|rfcbis }}">
+	        {{ doc.name|rfcbis }}
+	      </option>
+	    {% endif %}
           </select>
         </div>
       </div>
@@ -52,6 +57,11 @@ <h2>Revision differences</h2>
 	        ({{ time|date:"Y-m-d" }})
 	      </option>
 	    {% endfor %}
+	    {% if doc.name|rfcbis %}
+	      <option value="{{ doc.name|rfcbis }}">
+	        {{ doc.name|rfcbis }}
+	      </option>
+	    {% endif %}
           </select>
         </div>
       </div>