[morestatus] messages in status for histedit, graft, unshelve, merge states

Summary:
Continuation of D2502125. Let's help people when they're in a wierd states by
displaying a helpful message below the output of `hg status`

Example output:
  10/07 16:53 cdelahousse@dev4253 ~/local/clearmereg/testrepos/states/merge
  $ hg status
  M a

  # The repository is in an unfinished *merge* state.
  # Unresolved merge conflicts:
  #
  #     a
  #
  # To mark files as resolved:  hg resolve --mark FILE
  # To continue:                hg commit
  # To abort:                   hg update --clean .

For more example output, see the tests

Test Plan: See tests: `tests/test-morestatus.t`

Reviewers: #sourcecontrol, durham

Reviewed By: durham

Subscribers: akushner

Differential Revision: https://phabricator.fb.com/D2520272

Tasks: 8563305

Signature: t1:2520272:1444287977:b90b747538754ef4f4f0f8fab3e56f3aa288d3e5

morestatus.py

@@ -49,19 +49,34 @@ def helpmessage(ui, continuecmd, abortcmd):
     ui.warn(prefixlines(msg))
 
 def rebasemsg(ui):
-    return helpmessage(ui, 'hg rebase --continue', 'hg rebase --abort')
+    helpmessage(ui, 'hg rebase --continue', 'hg rebase --abort')
+
+def histeditmsg(ui):
+    helpmessage(ui, 'hg histedit --continue', 'hg histedit --abort')
+
+def unshelvemsg(ui):
+    helpmessage(ui, 'hg unshelve --continue', 'hg unshelve --abort')
+
+def graftmsg(ui):
+     # tweakdefaults requires `update` to have a rev hence the `.`
+    helpmessage(ui, 'hg graft --continue', 'hg update .')
+
+def mergemsg(ui):
+     # tweakdefaults requires `update` to have a rev hence the `.`
+    helpmessage(ui, 'hg commit', 'hg update --clean .    (warning: this will '
+            'erase all uncommitted changed)')
 
 STATES = (
     # (state, file path indicating states, helpful message function)
-    ('histedit', 'histedit-state', None),
+    ('histedit', 'histedit-state', histeditmsg),
     ('bisect', 'bisect.state', None),
-    ('graft', 'graftstate', None),
-    ('unshelve', 'unshelverebasestate', None),
+    ('graft', 'graftstate', graftmsg),
+    ('unshelve', 'unshelverebasestate', unshelvemsg),
     ('rebase', 'rebasestate', rebasemsg),
     # The merge state is part of a list that will be iterated over. It needs to
     # be last because some of the other unfinished states may also be in a merge
     # state (eg.  histedit, graft, etc). We want those to have priority.
-    ('merge', 'merge', None),
+    ('merge', 'merge', mergemsg),
 )
 
 def extsetup(ui):

tests/test-morestatus.t

@@ -24,6 +24,8 @@ Test status on histedit stop
   $ hg status
   
   # The repository is in an unfinished *histedit* state.
+  # To continue:                hg histedit --continue
+  # To abort:                   hg histedit --abort
 
 Test disabling output. Nothing should be shown
   $ hg status --config morestatus.show=False
@@ -67,6 +69,8 @@ Test graft state
   #     a
   # 
   # To mark files as resolved:  hg resolve --mark FILE
+  # To continue:                hg graft --continue
+  # To abort:                   hg update .
 
 Test hg status is normal after graft abort
   $ hg up --clean -q
@@ -98,6 +102,8 @@ Test unshelve state
   #     a
   # 
   # To mark files as resolved:  hg resolve --mark FILE
+  # To continue:                hg unshelve --continue
+  # To abort:                   hg unshelve --abort
 
 Test hg status is normal after unshelve abort
   $ hg unshelve --abort
@@ -148,3 +154,27 @@ Test hg status is normal after rebase abort
   $ hg status
   ? a.orig
   $ rm a.orig
+
+Test merge state
+  $ hg merge -q
+  warning: conflicts during merge.
+  merging a incomplete! (edit conflicts, then use 'hg resolve --mark')
+  [1]
+  $ hg status
+  M a
+  ? a.orig
+  
+  # The repository is in an unfinished *merge* state.
+  # Unresolved merge conflicts:
+  # 
+  #     a
+  # 
+  # To mark files as resolved:  hg resolve --mark FILE
+  # To continue:                hg commit
+  # To abort:                   hg update --clean .    (warning: this will erase all uncommitted changed)
+
+Test hg status is normal after merge abort
+  $ hg update --clean -q
+  $ hg status
+  ? a.orig
+  $ rm a.orig