shelve: make --keep option survive user intervention (issue5431)

shelve: make --keep option survive user intervention (issue5431)

Currently if user runs 'hg unshelve --keep' and merge conflicts
occur, the information about --keep provided by user is lost and
shelf is deleted after 'hg unshelve --continue'. This is obviously
not desired, so this patch fixes it.

--- a/hgext/shelve.py	Thu Nov 24 01:15:34 2016 +0000
+++ b/hgext/shelve.py	Wed Nov 23 14:58:52 2016 -0800
@@ -159,6 +159,8 @@
     """
     _version = 1
     _filename = 'shelvedstate'
+    _keep = 'keep'
+    _nokeep = 'nokeep'
 
     @classmethod
     def load(cls, repo):
@@ -175,6 +177,7 @@
             parents = [nodemod.bin(h) for h in fp.readline().split()]
             stripnodes = [nodemod.bin(h) for h in fp.readline().split()]
             branchtorestore = fp.readline().strip()
+            keep = fp.readline().strip() == cls._keep
         except (ValueError, TypeError) as err:
             raise error.CorruptedState(str(err))
         finally:
@@ -188,6 +191,7 @@
             obj.parents = parents
             obj.stripnodes = stripnodes
             obj.branchtorestore = branchtorestore
+            obj.keep = keep
         except error.RepoLookupError as err:
             raise error.CorruptedState(str(err))
 
@@ -195,7 +199,7 @@
 
     @classmethod
     def save(cls, repo, name, originalwctx, pendingctx, stripnodes,
-             branchtorestore):
+             branchtorestore, keep=False):
         fp = repo.vfs(cls._filename, 'wb')
         fp.write('%i\n' % cls._version)
         fp.write('%s\n' % name)
@@ -206,6 +210,7 @@
         fp.write('%s\n' %
                  ' '.join([nodemod.hex(n) for n in stripnodes]))
         fp.write('%s\n' % branchtorestore)
+        fp.write('%s\n' % (cls._keep if keep else cls._nokeep))
         fp.close()
 
     @classmethod
@@ -680,7 +685,7 @@
         stripnodes = [repo.changelog.node(rev)
                       for rev in xrange(oldtiprev, len(repo))]
         shelvedstate.save(repo, basename, pctx, tmpwctx, stripnodes,
-                          branchtorestore)
+                          branchtorestore, opts.get('keep'))
 
         util.rename(repo.join('rebasestate'),
                     repo.join('unshelverebasestate'))
@@ -782,6 +787,8 @@
 
         try:
             state = shelvedstate.load(repo)
+            if opts.get('keep') is None:
+                opts['keep'] = state.keep
         except IOError as err:
             if err.errno != errno.ENOENT:
                 raise

--- a/tests/test-shelve.t	Thu Nov 24 01:15:34 2016 +0000
+++ b/tests/test-shelve.t	Wed Nov 23 14:58:52 2016 -0800
@@ -1622,3 +1622,31 @@
   abort: no unshelve in progress
   [255]
   $ cd ..
+
+Unshelve respects --keep even if user intervention is needed
+  $ hg init unshelvekeep
+  $ echo 1 > file && hg ci -Am 1
+  adding file
+  $ echo 2 >> file
+  $ hg shelve
+  shelved as default
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  $ echo 3 >> file && hg ci -Am 13
+  $ hg shelve --list
+  default         (1s ago)    changes to: 1
+  $ hg unshelve --keep
+  unshelving change 'default'
+  rebasing shelved changes
+  rebasing 3:1d24e58054c8 "changes to: 1" (tip)
+  merging file
+  warning: conflicts while merging file! (edit, then use 'hg resolve --mark')
+  unresolved conflicts (see 'hg resolve', then 'hg unshelve --continue')
+  [1]
+  $ hg resolve --mark file
+  (no more unresolved files)
+  continue: hg unshelve --continue
+  $ hg unshelve --continue
+  rebasing 3:1d24e58054c8 "changes to: 1" (tip)
+  unshelve of 'default' complete
+  $ hg shelve --list
+  default         (1s ago)    changes to: 1