diff -r 9d9ff55d1bb1 -r 68aeeb4d4b8f tests/test-evolve-obshistory-complex.t
--- a/tests/test-evolve-obshistory-complex.t	Tue Nov 14 23:11:00 2017 +0100
+++ b/tests/test-evolve-obshistory-complex.t	Tue Nov 14 23:15:18 2017 +0100
@@ -68,7 +68,7 @@
 
   $ hg fold --exact -r 1 -r 2 --date "0 0" -m "fold0"
   2 changesets folded
-  4 new orphan changesets
+  4 new unstable changesets
   $ hg fold --exact -r 3 -r 4 --date "0 0" -m "fold1"
   2 changesets folded
   $ hg fold --exact -r 5 -r 6 --date "0 0" -m "fold2"
@@ -80,14 +80,14 @@
   |  parent:      4:868d2e0eb19c
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
-  |  instability: orphan
+  |  trouble:     unstable
   |  summary:     fold2
   |
   | o  changeset:   8:d15d0ffc75f6
   | |  parent:      2:c473644ee0e9
   | |  user:        test
   | |  date:        Thu Jan 01 00:00:00 1970 +0000
-  | |  instability: orphan
+  | |  trouble:     unstable
   | |  summary:     fold1
   | |
   | | o  changeset:   7:b868bc49b0a4
@@ -99,25 +99,25 @@
   x | |  changeset:   4:868d2e0eb19c
   | | |  user:        test
   | | |  date:        Thu Jan 01 00:00:00 1970 +0000
-  | | |  obsolete:    rewritten as 8:d15d0ffc75f6
+  | | |  obsolete:    rewritten as d15d0ffc75f6
   | | |  summary:     D
   | | |
   x | |  changeset:   3:a8df460dbbfe
   |/ /   user:        test
   | |    date:        Thu Jan 01 00:00:00 1970 +0000
-  | |    obsolete:    rewritten as 8:d15d0ffc75f6
+  | |    obsolete:    rewritten as d15d0ffc75f6
   | |    summary:     C
   | |
   x |  changeset:   2:c473644ee0e9
   | |  user:        test
   | |  date:        Thu Jan 01 00:00:00 1970 +0000
-  | |  obsolete:    rewritten as 7:b868bc49b0a4
+  | |  obsolete:    rewritten as b868bc49b0a4
   | |  summary:     B
   | |
   x |  changeset:   1:2a34000d3544
   |/   user:        test
   |    date:        Thu Jan 01 00:00:00 1970 +0000
-  |    obsolete:    rewritten as 7:b868bc49b0a4
+  |    obsolete:    rewritten as b868bc49b0a4
   |    summary:     A
   |
   o  changeset:   0:ea207398892e
@@ -236,27 +236,27 @@
   |  tag:         tip
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
-  |  instability: orphan
+  |  trouble:     unstable
   |  summary:     fold2
   |
   o  changeset:   14:ec31316faa9d
   |  parent:      4:868d2e0eb19c
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
-  |  instability: orphan
+  |  trouble:     unstable
   |  summary:     fold2
   |
   | o  changeset:   13:d0f33db50670
   | |  user:        test
   | |  date:        Thu Jan 01 00:00:00 1970 +0000
-  | |  instability: orphan
+  | |  trouble:     unstable
   | |  summary:     fold1
   | |
   | o  changeset:   12:7b3290f6e0a0
   | |  parent:      2:c473644ee0e9
   | |  user:        test
   | |  date:        Thu Jan 01 00:00:00 1970 +0000
-  | |  instability: orphan
+  | |  trouble:     unstable
   | |  summary:     fold1
   | |
   | | o  changeset:   11:e036916b63ea
@@ -273,25 +273,25 @@
   x | |  changeset:   4:868d2e0eb19c
   | | |  user:        test
   | | |  date:        Thu Jan 01 00:00:00 1970 +0000
-  | | |  obsolete:    split as 12:7b3290f6e0a0, 13:d0f33db50670
+  | | |  obsolete:    split as 7b3290f6e0a0, d0f33db50670
   | | |  summary:     D
   | | |
   x | |  changeset:   3:a8df460dbbfe
   |/ /   user:        test
   | |    date:        Thu Jan 01 00:00:00 1970 +0000
-  | |    obsolete:    split as 12:7b3290f6e0a0, 13:d0f33db50670
+  | |    obsolete:    split as 7b3290f6e0a0, d0f33db50670
   | |    summary:     C
   | |
   x |  changeset:   2:c473644ee0e9
   | |  user:        test
   | |  date:        Thu Jan 01 00:00:00 1970 +0000
-  | |  obsolete:    split as 10:19e14c8397fc, 11:e036916b63ea
+  | |  obsolete:    split as 19e14c8397fc, e036916b63ea
   | |  summary:     B
   | |
   x |  changeset:   1:2a34000d3544
   |/   user:        test
   |    date:        Thu Jan 01 00:00:00 1970 +0000
-  |    obsolete:    split as 10:19e14c8397fc, 11:e036916b63ea
+  |    obsolete:    split as 19e14c8397fc, e036916b63ea
   |    summary:     A
   |
   o  changeset:   0:ea207398892e
@@ -312,21 +312,21 @@
   |  tag:         tip
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
-  |  instability: orphan
+  |  trouble:     unstable
   |  summary:     fold2
   |
   o  changeset:   14:ec31316faa9d
   |  parent:      4:868d2e0eb19c
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
-  |  instability: orphan
+  |  trouble:     unstable
   |  summary:     fold2
   |
   | o  changeset:   12:7b3290f6e0a0
   | |  parent:      2:c473644ee0e9
   | |  user:        test
   | |  date:        Thu Jan 01 00:00:00 1970 +0000
-  | |  instability: orphan
+  | |  trouble:     unstable
   | |  summary:     fold1
   | |
   | | o  changeset:   10:19e14c8397fc
@@ -338,25 +338,25 @@
   x | |  changeset:   4:868d2e0eb19c
   | | |  user:        test
   | | |  date:        Thu Jan 01 00:00:00 1970 +0000
-  | | |  obsolete:    split as 12:7b3290f6e0a0, 14:ec31316faa9d
+  | | |  obsolete:    split as 7b3290f6e0a0, ec31316faa9d
   | | |  summary:     D
   | | |
   x | |  changeset:   3:a8df460dbbfe
   |/ /   user:        test
   | |    date:        Thu Jan 01 00:00:00 1970 +0000
-  | |    obsolete:    split as 12:7b3290f6e0a0, 14:ec31316faa9d
+  | |    obsolete:    split as 7b3290f6e0a0, ec31316faa9d
   | |    summary:     C
   | |
   x |  changeset:   2:c473644ee0e9
   | |  user:        test
   | |  date:        Thu Jan 01 00:00:00 1970 +0000
-  | |  obsolete:    split as 10:19e14c8397fc, 12:7b3290f6e0a0
+  | |  obsolete:    split as 19e14c8397fc, 7b3290f6e0a0
   | |  summary:     B
   | |
   x |  changeset:   1:2a34000d3544
   |/   user:        test
   |    date:        Thu Jan 01 00:00:00 1970 +0000
-  |    obsolete:    split as 10:19e14c8397fc, 12:7b3290f6e0a0
+  |    obsolete:    split as 19e14c8397fc, 7b3290f6e0a0
   |    summary:     A
   |
   o  changeset:   0:ea207398892e