--- a/tests/test-topic-stack.t	Sun Sep 10 22:22:06 2017 +0900
+++ b/tests/test-topic-stack.t	Thu Sep 07 16:45:57 2017 +0200
@@ -430,3 +430,123 @@
   abort: cannot resolve "thisdoesnotexist": no such topic found
   [255]
 
+Complex cases where commits with same topic are not consecutive but are linear
+==============================================================================
+
+  $ hg log --graph
+  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 {} public c_b
+  |
+  o  0 default {} public c_a
+  
+Converting into a linear chain
+  $ hg rebase -s 8 -d 15
+  rebasing 8:215bc359096a "c_e"
+  rebasing 9:ec9267b3f33f "c_f"
+
+  $ hg log -G
+  o  17 default {foo} draft c_f
+  |
+  o  16 default {foo} draft c_e
+  |
+  o  15 default {foo} draft c_h
+  |
+  o  14 default {foo} draft c_g
+  |
+  @  13 default {foo} draft c_D
+  |
+  o  2 default {foo} draft c_c
+  |
+  o  1 default {} public c_b
+  |
+  o  0 default {} public c_a
+  
+Changing topics on some commits in between
+  $ hg topic foobar -r 'desc(c_e) + desc(c_D)'
+  switching to topic foobar
+  changed topic on 2 changes
+  $ hg log -G
+  @  19 default {foobar} draft c_D
+  |
+  | o  18 default {foobar} draft c_e
+  | |
+  | | o  17 default {foo} draft c_f
+  | | |
+  | | x  16 default {foo} draft c_e
+  | |/
+  | o  15 default {foo} draft c_h
+  | |
+  | o  14 default {foo} draft c_g
+  | |
+  | x  13 default {foo} draft c_D
+  |/
+  o  2 default {foo} draft c_c
+  |
+  o  1 default {} public c_b
+  |
+  o  0 default {} public c_a
+  
+  $ hg rebase -s 17 -d 18
+  rebasing 17:77082e55de88 "c_f"
+  switching to topic foo
+  switching to topic foobar
+  $ hg rebase -s 14 -d 19
+  rebasing 14:0c3e8aed985d "c_g"
+  switching to topic foo
+  rebasing 15:b9e4f3709bc5 "c_h"
+  rebasing 18:4bc813530301 "c_e"
+  switching to topic foobar
+  rebasing 20:4406ea4be852 "c_f" (tip)
+  switching to topic foo
+  switching to topic foobar
+  $ hg up
+  3 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  $ hg log --graph
+  o  24 default {foo} draft c_f
+  |
+  @  23 default {foobar} draft c_e
+  |
+  o  22 default {foo} draft c_h
+  |
+  o  21 default {foo} draft c_g
+  |
+  o  19 default {foobar} draft c_D
+  |
+  o  2 default {foo} draft c_c
+  |
+  o  1 default {} public c_b
+  |
+  o  0 default {} public c_a
+  
+XXX: The following should show single heads
+  $ hg stack
+  ### topic: foobar (2 heads)
+  ### branch: default, 3 behind
+  t2: c_D
+    ^ c_c
+  t1@ c_e (current)
+  t0^ c_h (base)
+
+  $ hg stack foo
+  ### topic: foo (3 heads)
+  ### branch: default, ambigious rebase destination
+  t4: c_c
+    ^ c_b
+  t3: c_h
+  t2: c_g
+    ^ c_D
+  t1: c_f
+  t0^ c_e (base)