--- a/mercurial/commands.py	Fri Apr 27 01:35:00 2018 -0400
+++ b/mercurial/commands.py	Mon May 07 19:43:43 2018 -0700
@@ -5583,18 +5583,19 @@
             repo = scmutil.unhidehashlikerevs(repo, [rev], 'nowarn')
         ctx = scmutil.revsingle(repo, rev, rev)
         rev = ctx.rev()
-        if ctx.hidden():
+        hidden = ctx.hidden()
+        repo.ui.setconfig('ui', 'forcemerge', opts.get(r'tool'), 'update')
+
+        ret = hg.updatetotally(ui, repo, rev, brev, clean=clean,
+                               updatecheck=updatecheck)
+        if hidden:
             ctxstr = ctx.hex()[:12]
-            ui.warn(_("updating to a hidden changeset %s\n") % ctxstr)
+            ui.warn(_("updated to hidden changeset %s\n") % ctxstr)
 
             if ctx.obsolete():
                 obsfatemsg = obsutil._getfilteredreason(repo, ctxstr, ctx)
                 ui.warn("(%s)\n" % obsfatemsg)
-
-        repo.ui.setconfig('ui', 'forcemerge', opts.get(r'tool'), 'update')
-
-        return hg.updatetotally(ui, repo, rev, brev, clean=clean,
-                                updatecheck=updatecheck)
+        return ret
 
 @command('verify', [])
 def verify(ui, repo):

--- a/tests/test-directaccess.t	Fri Apr 27 01:35:00 2018 -0400
+++ b/tests/test-directaccess.t	Mon May 07 19:43:43 2018 -0700
@@ -156,9 +156,9 @@
 `hg update`
 
   $ hg up 28ad74
-  updating to a hidden changeset 28ad74487de9
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  updated to hidden changeset 28ad74487de9
   (hidden revision '28ad74487de9' was rewritten as: 2443a0e66469)
-  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
 
   $ hg up 3
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved

--- a/tests/test-log.t	Fri Apr 27 01:35:00 2018 -0400
+++ b/tests/test-log.t	Mon May 07 19:43:43 2018 -0700
@@ -1943,7 +1943,7 @@
 test that parent prevent a changeset to be hidden
 
   $ hg up 1 -q --hidden
-  updating to a hidden changeset a765632148dc
+  updated to hidden changeset a765632148dc
   (hidden revision 'a765632148dc' is pruned)
   $ hg log --template='{rev}:{node}\n'
   1:a765632148dc55d38c35c4f247c618701886cb2f

--- a/tests/test-obshistory.t	Fri Apr 27 01:35:00 2018 -0400
+++ b/tests/test-obshistory.t	Mon May 07 19:43:43 2018 -0700
@@ -55,9 +55,9 @@
   (use --hidden to access hidden revisions)
   [255]
   $ hg update --hidden "desc(A0)"
-  updating to a hidden changeset 471f378eab4c
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  updated to hidden changeset 471f378eab4c
   (hidden revision '471f378eab4c' was rewritten as: 4ae3a4151de9)
-  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
 
 Test output with pruned commit
 ==============================
@@ -118,9 +118,9 @@
   (use --hidden to access hidden revisions)
   [255]
   $ hg up --hidden -r 'desc(B0)'
-  updating to a hidden changeset 0dec01379d3b
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  updated to hidden changeset 0dec01379d3b
   (hidden revision '0dec01379d3b' is pruned)
-  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
 
 Test output with splitted commit
 ================================
@@ -195,9 +195,9 @@
   (use --hidden to access hidden revisions)
   [255]
   $ hg update --hidden 'min(desc(A0))'
-  updating to a hidden changeset 471597cad322
+  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  updated to hidden changeset 471597cad322
   (hidden revision '471597cad322' was split as: 337fec4d2edc, f257fde29c7a)
-  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
 
 Test output with lots of splitted commit
 ========================================
@@ -294,9 +294,9 @@
   (use --hidden to access hidden revisions)
   [255]
   $ hg update --hidden 'min(desc(A0))'
-  updating to a hidden changeset de7290d8b885
+  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  updated to hidden changeset de7290d8b885
   (hidden revision 'de7290d8b885' was split as: 337fec4d2edc, f257fde29c7a and 2 more)
-  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
 
 Test output with folded commit
 ==============================
@@ -373,17 +373,17 @@
   (use --hidden to access hidden revisions)
   [255]
   $ hg update --hidden 'desc(A0)'
-  updating to a hidden changeset 471f378eab4c
+  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
+  updated to hidden changeset 471f378eab4c
   (hidden revision '471f378eab4c' was rewritten as: eb5a0daa2192)
-  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
   $ hg update 0dec01379d3b
   abort: hidden revision '0dec01379d3b' was rewritten as: eb5a0daa2192!
   (use --hidden to access hidden revisions)
   [255]
   $ hg update --hidden 'desc(B0)'
-  updating to a hidden changeset 0dec01379d3b
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  updated to hidden changeset 0dec01379d3b
   (hidden revision '0dec01379d3b' was rewritten as: eb5a0daa2192)
-  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
 
 Test output with divergence
 ===========================
@@ -416,9 +416,9 @@
      summary:     ROOT
   
   $ hg update --hidden 'desc(A0)'
-  updating to a hidden changeset 471f378eab4c
+  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  updated to hidden changeset 471f378eab4c
   (hidden revision '471f378eab4c' was rewritten as: fdf9bde5129a)
-  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ hg commit --amend -m "A2"
   2 new content-divergent changesets
   $ hg log --hidden -G
@@ -456,9 +456,9 @@
   (use --hidden to access hidden revisions)
   [255]
   $ hg update --hidden 'desc(A0)'
-  updating to a hidden changeset 471f378eab4c
+  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  updated to hidden changeset 471f378eab4c
   (hidden revision '471f378eab4c' has diverged)
-  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
 
 Test output with amended + folded commit
 ========================================
@@ -551,13 +551,13 @@
   (use --hidden to access hidden revisions)
   [255]
   $ hg update --hidden 'desc(A0)'
-  updating to a hidden changeset 471f378eab4c
+  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
+  updated to hidden changeset 471f378eab4c
   (hidden revision '471f378eab4c' was rewritten as: eb5a0daa2192)
-  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
   $ hg update --hidden 0dec01379d3b
-  updating to a hidden changeset 0dec01379d3b
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  updated to hidden changeset 0dec01379d3b
   (hidden revision '0dec01379d3b' was rewritten as: eb5a0daa2192)
-  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ hg update 0dec01379d3b
   0 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ hg update --hidden 'desc(B0)'

--- a/tests/test-obsmarker-template.t	Fri Apr 27 01:35:00 2018 -0400
+++ b/tests/test-obsmarker-template.t	Mon May 07 19:43:43 2018 -0700
@@ -75,9 +75,9 @@
 Check templates
 ---------------
   $ hg up 'desc(A0)' --hidden
-  updating to a hidden changeset 471f378eab4c
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  updated to hidden changeset 471f378eab4c
   (hidden revision '471f378eab4c' was rewritten as: d004c8f274b9)
-  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
 
 Predecessors template should show current revision as it is the working copy
   $ hg tlog
@@ -148,9 +148,9 @@
      summary:     ROOT
   
   $ hg up 'desc(A1)' --hidden
-  updating to a hidden changeset a468dc9b3633
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  updated to hidden changeset a468dc9b3633
   (hidden revision 'a468dc9b3633' was rewritten as: d004c8f274b9)
-  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
 
 Predecessors template should show current revision as it is the working copy
   $ hg tlog
@@ -417,9 +417,9 @@
 ---------------
 
   $ hg up 'obsolete()' --hidden
-  updating to a hidden changeset 471597cad322
+  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  updated to hidden changeset 471597cad322
   (hidden revision '471597cad322' was split as: 337fec4d2edc, f257fde29c7a)
-  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
 
 Predecessors template should show current revision as it is the working copy
   $ hg tlog
@@ -627,9 +627,9 @@
 ---------------
 
   $ hg up 'desc(A0)' --hidden
-  updating to a hidden changeset 471f378eab4c
+  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
+  updated to hidden changeset 471f378eab4c
   (hidden revision '471f378eab4c' was rewritten as: eb5a0daa2192)
-  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
 
 Predecessors template should show current revision as it is the working copy
   $ hg tlog
@@ -653,9 +653,9 @@
   o  ea207398892e
   
   $ hg up 'desc(B0)' --hidden
-  updating to a hidden changeset 0dec01379d3b
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  updated to hidden changeset 0dec01379d3b
   (hidden revision '0dec01379d3b' was rewritten as: eb5a0daa2192)
-  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
 
 Predecessors template should show both predecessors as they should be both
 displayed
@@ -820,9 +820,9 @@
      summary:     ROOT
   
   $ hg update --hidden 'desc(A0)'
-  updating to a hidden changeset 471f378eab4c
+  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  updated to hidden changeset 471f378eab4c
   (hidden revision '471f378eab4c' was rewritten as: fdf9bde5129a)
-  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ hg commit --amend -m "A2"
   2 new content-divergent changesets
   $ hg log --hidden -G
@@ -894,9 +894,9 @@
 ---------------
 
   $ hg up 'desc(A0)' --hidden
-  updating to a hidden changeset 471f378eab4c
+  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  updated to hidden changeset 471f378eab4c
   (hidden revision '471f378eab4c' has diverged)
-  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
 
 Predecessors template should show current revision as it is the working copy
   $ hg tlog
@@ -1161,9 +1161,9 @@
 ---------------
 
   $ hg up 'desc(A0)' --hidden
-  updating to a hidden changeset 471f378eab4c
+  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
+  updated to hidden changeset 471f378eab4c
   (hidden revision '471f378eab4c' was rewritten as: eb5a0daa2192)
-  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
 
 Predecessors template should show current revision as it is the working copy
   $ hg tlog
@@ -1187,9 +1187,9 @@
   o  ea207398892e
   
   $ hg up 'desc(B0)' --hidden
-  updating to a hidden changeset 0dec01379d3b
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  updated to hidden changeset 0dec01379d3b
   (hidden revision '0dec01379d3b' was rewritten as: eb5a0daa2192)
-  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
 
 Predecessors template should both predecessors as they are visible
   $ hg tlog
@@ -1219,9 +1219,9 @@
   o  ea207398892e
   
   $ hg up 'desc(B1)' --hidden
-  updating to a hidden changeset b7ea6d14e664
+  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  updated to hidden changeset b7ea6d14e664
   (hidden revision 'b7ea6d14e664' was rewritten as: eb5a0daa2192)
-  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
 
 Predecessors template should both predecessors as they are visible
   $ hg tlog
@@ -1623,9 +1623,9 @@
   
 
   $ hg up -r "desc(B0)" --hidden
-  updating to a hidden changeset 0dec01379d3b
+  2 files updated, 0 files merged, 1 files removed, 0 files unresolved
+  updated to hidden changeset 0dec01379d3b
   (hidden revision '0dec01379d3b' is pruned)
-  2 files updated, 0 files merged, 1 files removed, 0 files unresolved
   $ hg tlog
   o  f897c6137566
   |    Predecessors: 2:0dec01379d3b
@@ -2087,9 +2087,9 @@
   o  ea207398892e
   
   $ hg up --hidden 4
-  updating to a hidden changeset 9bd10a0775e4
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  updated to hidden changeset 9bd10a0775e4
   (hidden revision '9bd10a0775e4' has diverged)
-  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ hg rebase -r 7 -d 8 --config extensions.rebase=
   rebasing 7:ba2ed02b0c9a "Add A,B,C"
   $ hg tlog
@@ -2333,9 +2333,9 @@
   obsoleted 1 changesets
 
   $ hg up -r "desc(A0)" --hidden
-  updating to a hidden changeset 471f378eab4c
+  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  updated to hidden changeset 471f378eab4c
   (hidden revision '471f378eab4c' is pruned)
-  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ hg commit --amend -m "A2"
   $ hg debugobsolete --record-parent `getid "."`
   obsoleted 1 changesets
@@ -2344,9 +2344,9 @@
 ------------
 
   $ hg up "desc(A0)" --hidden
-  updating to a hidden changeset 471f378eab4c
+  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  updated to hidden changeset 471f378eab4c
   (hidden revision '471f378eab4c' is pruned)
-  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ hg tlog
   @  471f378eab4c
   |
@@ -2499,9 +2499,9 @@
 ---------------
 
   $ hg up 'desc("A0")' --hidden
-  updating to a hidden changeset 471597cad322
+  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  updated to hidden changeset 471597cad322
   (hidden revision '471597cad322' is pruned)
-  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
 
 # todo: the obsfate output is not ideal
   $ hg fatelog
@@ -2512,9 +2512,9 @@
   o  ea207398892e
   
   $ hg up -r 'desc("A2")' --hidden
-  updating to a hidden changeset 0d0ef4bdf70e
+  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  updated to hidden changeset 0d0ef4bdf70e
   (hidden revision '0d0ef4bdf70e' is pruned)
-  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
 
   $ hg fatelog --hidden
   @  0d0ef4bdf70e

--- a/tests/test-obsolete.t	Fri Apr 27 01:35:00 2018 -0400
+++ b/tests/test-obsolete.t	Mon May 07 19:43:43 2018 -0700
@@ -62,7 +62,7 @@
   $ hg tip
   -1:000000000000 (public) [tip ] 
   $ hg up --hidden tip --quiet
-  updating to a hidden changeset 97b7c2d76b18
+  updated to hidden changeset 97b7c2d76b18
   (hidden revision '97b7c2d76b18' is pruned)
 
 Killing a single changeset with itself should fail

--- a/tests/test-rebase-obsolete.t	Fri Apr 27 01:35:00 2018 -0400
+++ b/tests/test-rebase-obsolete.t	Mon May 07 19:43:43 2018 -0700
@@ -281,7 +281,7 @@
 even though it is hidden (until we're moved there).
 
   $ hg --hidden up -qr 'first(hidden())'
-  updating to a hidden changeset 42ccdea3bb16
+  updated to hidden changeset 42ccdea3bb16
   (hidden revision '42ccdea3bb16' is pruned)
   $ hg rebase --rev 13 --dest 15
   rebasing 13:98f6af4ee953 "C"
@@ -642,9 +642,9 @@
 Test hidden changesets in the rebase set (issue4504)
 
   $ hg up --hidden 9
-  updating to a hidden changeset 4bde274eefcf
+  3 files updated, 0 files merged, 1 files removed, 0 files unresolved
+  updated to hidden changeset 4bde274eefcf
   (hidden revision '4bde274eefcf' was rewritten as: acd174b7ab39)
-  3 files updated, 0 files merged, 1 files removed, 0 files unresolved
   $ echo J > J
   $ hg add J
   $ hg commit -m J
@@ -764,9 +764,9 @@
   $ hg commit --amend -m B1
   $ hg commit --amend -m B2
   $ hg up --hidden 'desc(B0)'
-  updating to a hidden changeset a8b11f55fb19
+  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  updated to hidden changeset a8b11f55fb19
   (hidden revision 'a8b11f55fb19' was rewritten as: 261e70097290)
-  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ echo C > C
   $ hg add C
   $ hg commit -m C
@@ -790,9 +790,9 @@
 Even when the chain include missing node
 
   $ hg up --hidden 'desc(B0)'
-  updating to a hidden changeset a8b11f55fb19
+  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
+  updated to hidden changeset a8b11f55fb19
   (hidden revision 'a8b11f55fb19' was rewritten as: 261e70097290)
-  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
   $ echo D > D
   $ hg add D
   $ hg commit -m D
@@ -909,9 +909,9 @@
   $ hg add bar
   $ hg commit --amend -m "10'"
   $ hg up 10 --hidden
-  updating to a hidden changeset 121d9e3bc4c6
+  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
+  updated to hidden changeset 121d9e3bc4c6
   (hidden revision '121d9e3bc4c6' was rewritten as: 77d874d096a2)
-  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
   $ echo "bar" > foo
   $ hg add foo
   $ hg commit -m "bar foo"
@@ -1706,7 +1706,7 @@
   $ rm .hg/localtags
 
   $ hg update -q $C --hidden
-  updating to a hidden changeset 7829726be4dc
+  updated to hidden changeset 7829726be4dc
   (hidden revision '7829726be4dc' is pruned)
   $ hg rebase -s $B -d $D
   rebasing 1:2ec65233581b "B"

--- a/tests/test-update-branches.t	Fri Apr 27 01:35:00 2018 -0400
+++ b/tests/test-update-branches.t	Mon May 07 19:43:43 2018 -0700
@@ -516,11 +516,33 @@
   $ hg bookmarks
    * bm                        5:ff252e8273df
 
+Test that we abort before we warn about the hidden commit if the working
+directory is dirty
+  $ echo conflict > a
+  $ hg up --hidden 3
+  abort: uncommitted changes
+  (commit or update --clean to discard changes)
+  [255]
+
+Test that we still warn also when there are conflicts
+  $ hg up -m --hidden 3
+  merging a
+  warning: conflicts while merging a! (edit, then use 'hg resolve --mark')
+  0 files updated, 0 files merged, 0 files removed, 1 files unresolved
+  use 'hg resolve' to retry unresolved file merges
+  (leaving bookmark bm)
+  updated to hidden changeset 6efa171f091b
+  (hidden revision '6efa171f091b' was rewritten as: d047485b3896)
+  [1]
+  $ hg revert -r . a
+  $ hg resolve -m
+  (no more unresolved files)
+
 Test that 4 is detected as the no-argument destination from 3 and also moves
 the bookmark with it
   $ hg up --quiet 0          # we should be able to update to 3 directly
   $ hg up --quiet --hidden 3 # but not implemented yet.
-  updating to a hidden changeset 6efa171f091b
+  updated to hidden changeset 6efa171f091b
   (hidden revision '6efa171f091b' was rewritten as: d047485b3896)
   $ hg book -f bm
   $ hg up
@@ -532,7 +554,7 @@
 Test that 5 is detected as a valid destination from 1
   $ hg up --quiet 0          # we should be able to update to 3 directly
   $ hg up --quiet --hidden 3 # but not implemented yet.
-  updating to a hidden changeset 6efa171f091b
+  updated to hidden changeset 6efa171f091b
   (hidden revision '6efa171f091b' was rewritten as: d047485b3896)
   $ hg up 5
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved