abort: added support for unshelve This patch adds the support for shelve in `hg abort` plan. For this the logic to load a `shelvedstate` and the error handling for it had been shifted to a seperate function `_loadunshelvedstate()`. This returns a tuple with `state` file and `opts.` `hgabortunshelve()` has been created for independent calls. In case abortion of `unshelve` is called via `hg abort` the `shelvedstate` needs to be loaded seperately. This has been ensured by `_loadunshelvedstate()` `hgabortunshelve()` is then registered as `abortfunc` for state detection API. Results are shown as tests. Differential Revision: https://phab.mercurial-scm.org/D6579

--- a/mercurial/state.py	Wed Jul 10 23:11:55 2019 +0530
+++ b/mercurial/state.py	Wed Jun 26 22:15:07 2019 +0530
@@ -194,10 +194,6 @@
         _unfinishedstates.insert(0, statecheckobj)
 
 addunfinished(
-    'unshelve', fname='shelvedstate', continueflag=True,
-    cmdmsg=_('unshelve already in progress')
-)
-addunfinished(
     'update', fname='updatestate', clearable=True,
     cmdmsg=_('last update was interrupted'),
     cmdhint=_("use 'hg update' to get a consistent checkout"),