--- a/hgext3rd/topic/__init__.py	Mon Mar 14 19:22:21 2016 +0000
+++ b/hgext3rd/topic/__init__.py	Mon Mar 14 23:37:58 2016 +0000
@@ -46,7 +46,8 @@
 cmdtable = {}
 command = cmdutil.command(cmdtable)
 colortable = {'topic.stack.index': 'yellow',
-              'topic.stack.state.clean': 'dim',
+              'topic.stack.state.base': 'dim',
+              'topic.stack.state.clean': 'green',
               'topic.stack.index.current': 'cyan', # random pick
               'topic.stack.state.current': 'cyan bold', # random pick
               'topic.stack.desc.current': 'cyan', # random pick

--- a/hgext3rd/topic/stack.py	Mon Mar 14 19:22:21 2016 +0000
+++ b/hgext3rd/topic/stack.py	Mon Mar 14 23:37:58 2016 +0000
@@ -19,7 +19,26 @@
     if not topic:
         raise error.Abort(_('no active topic to list'))
     fm = ui.formatter('topicstack', opts)
+    prev = None
     for idx, r in enumerate(getstack(repo, topic)):
+        ctx =  repo[r]
+        p1 = ctx.p1()
+        if p1.obsolete():
+            p1 = repo[_singlesuccessor(repo, p1)]
+        if p1.rev() != prev:
+            # display the parent of the chanset
+            state = 'base'
+            symbol= '_'
+            fm.startitem()
+            fm.plain('  ') # XXX 2 is the right padding by chance
+            fm.write('topic.stack.state', '%s', symbol,
+                     label='topic.stack.state topic.stack.state.%s' % state)
+            fm.plain(' ')
+            fm.write('topic.stack.desc', '%s',
+                     p1.description().splitlines()[0],
+                     label='topic.stack.desc topic.stack.desc.%s' % state)
+            fm.plain('\n')
+            fm.end()
         # super crude initial version
         symbol = ':'
         state = 'clean'
@@ -35,12 +54,13 @@
         fm.write('topic.stack.state.symbol', '%s', symbol,
                  label='topic.stack.state topic.stack.state.%s' % state)
         fm.plain(' ')
-        fm.write('topic.stack.desc', '%s', repo[r].description().splitlines()[0],
+        fm.write('topic.stack.desc', '%s', ctx.description().splitlines()[0],
                  label='topic.stack.desc topic.stack.desc.%s' % state)
         fm.condwrite(state != 'clean', 'topic.stack.state', ' (%s)', state,
                     label='topic.stack.state topic.stack.state.%s' % state)
         fm.plain('\n')
         fm.end()
+        prev = r
 
 # Copied from evolve 081605c2e9b6
 
@@ -64,11 +84,11 @@
     # one depending on A) that we can remove from the dependency graph and add
     # to the ordering. We progress in a similar fashion until the ordering is
     # built
-    solvablerevs = collections.deque([r for r in sorted(dependencies.keys())
-                                      if not dependencies[r]])
+    solvablerevs = [r for r in sorted(dependencies.keys())
+                    if not dependencies[r]]
     ordering = []
     while solvablerevs:
-        rev = solvablerevs.popleft()
+        rev = solvablerevs.pop()
         for dependent in rdependencies[rev]:
             dependencies[dependent].remove(rev)
             if not dependencies[dependent]:

--- a/tests/test-topic-stack.t	Mon Mar 14 19:22:21 2016 +0000
+++ b/tests/test-topic-stack.t	Mon Mar 14 23:37:58 2016 +0000
@@ -57,6 +57,7 @@
   $ hg topic
    * foo
   $ hg topic --list
+    _ c_b
   t0: c_c
   t1: c_d
   t2: c_e
@@ -104,7 +105,115 @@
   o  0 default {} draft c_a
   
   $ hg topic --list
+    _ c_b
   t0: c_c
   t1@ c_d (current)
   t2$ c_e (unstable)
   t3$ c_f (unstable)
+
+Case with multiple heads on the topic
+-------------------------------------
+
+Make things linear again
+
+  $ hg rebase -s 'desc(c_e)' -d 'desc(c_d) - obsolete()'
+  rebasing 4:91fa8808d101 "c_e"
+  rebasing 5:4ec5094907b7 "c_f"
+  $ hg log -G
+  o  9 default {foo} draft c_f
+  |
+  o  8 default {foo} draft c_e
+  |
+  @  7 default {foo} draft c_d
+  |
+  o  2 default {foo} draft c_c
+  |
+  o  1 default {} draft c_b
+  |
+  o  0 default {} draft c_a
+  
+
+
+Create the second branch
+
+  $ hg up 'desc(c_d)'
+  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  $ echo aaa > ggg
+  $ hg add ggg
+  $ hg commit -m c_g
+  created new head
+  $ echo aaa > hhh
+  $ hg add hhh
+  $ hg commit -m c_h
+  created new head
+  $ hg log -G
+  @  11 default {foo} draft c_h
+  |
+  o  10 default {foo} draft c_g
+  |
+  | o  9 default {foo} draft c_f
+  | |
+  | o  8 default {foo} draft c_e
+  |/
+  o  7 default {foo} draft c_d
+  |
+  o  2 default {foo} draft c_c
+  |
+  o  1 default {} draft c_b
+  |
+  o  0 default {} draft c_a
+  
+
+Test output
+
+  $ hg top -l
+    _ c_b
+  t0: c_c
+  t1: c_d
+  t2: c_g
+  t3@ c_h (current)
+    _ c_d
+  t4: c_e
+  t5: c_f
+
+Case with multiple heads on the topic with unstability involved
+---------------------------------------------------------------
+
+We amend the message to make sure the display base pick the right changeset
+
+  $ hg up 'desc(c_d)'
+  0 files updated, 0 files merged, 2 files removed, 0 files unresolved
+  $ echo ccc > ddd
+  $ hg commit --amend -m 'c_D' 
+  $ hg rebase -d . -s 'desc(c_g)'
+  rebasing 10:11286b4fcb3d "c_g"
+  rebasing 11:3ad57527186d "c_h"
+  $ hg log -G
+  o  15 default {foo} draft c_h
+  |
+  o  14 default {foo} draft c_g
+  |
+  @  13 default {foo} draft c_D
+  |
+  | o  9 default {foo} draft c_f
+  | |
+  | o  8 default {foo} draft c_e
+  | |
+  | x  7 default {foo} draft c_d
+  |/
+  o  2 default {foo} draft c_c
+  |
+  o  1 default {} draft c_b
+  |
+  o  0 default {} draft c_a
+  
+
+  $ hg topic --list
+    _ c_b
+  t0: c_c
+  t1@ c_D (current)
+  t2: c_g
+  t3: c_h
+    _ c_D
+  t4$ c_e (unstable)
+  t5$ c_f (unstable)