diff --git a/mercurial/commands.py b/mercurial/commands.py
--- a/mercurial/commands.py
+++ b/mercurial/commands.py
@@ -6259,6 +6259,11 @@
     with repo.wlock():
         return shelvemod._dounshelve(ui, repo, *shelved, **opts)
 
+statemod.addunfinished(
+    'unshelve', fname='shelvedstate', continueflag=True,
+    cmdmsg=_('unshelve already in progress'), abortfunc=shelvemod.unshelveabort
+)
+
 @command('update|up|checkout|co',
     [('C', 'clean', None, _('discard uncommitted changes (no backup)')),
     ('c', 'check', None, _('require clean working directory')),
diff --git a/mercurial/shelve.py b/mercurial/shelve.py
--- a/mercurial/shelve.py
+++ b/mercurial/shelve.py
@@ -26,6 +26,7 @@
 import errno
 import itertools
 import stat
+import sys
 
 from .i18n import _
 from . import (
@@ -624,9 +625,41 @@
         raise error.Abort(_('working directory parents do not match unshelve '
                            'state'))
 
-def unshelveabort(ui, repo, state, opts):
+def _loadshelvedstate(ui, repo, continuef=False, abortf=False, **opts):
+    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
+        cmdutil.wrongtooltocontinue(repo, _('unshelve'))
+    except error.CorruptedState as err:
+        ui.debug(pycompat.bytestr(err) + '\n')
+        if continuef:
+            msg = _('corrupted shelved state file')
+            hint = _('please run hg unshelve --abort to abort unshelve '
+                     'operation')
+            raise error.Abort(msg, hint=hint)
+        elif abortf:
+            msg = _('could not read shelved state file, your working copy '
+                    'may be in an unexpected state\nplease update to some '
+                    'commit\n')
+            ui.warn(msg)
+            shelvedstate.clear(repo)
+        sys.exit()
+    return (state, opts)
+
+def unshelveabort(ui, repo, state=None, **opts):
     """subcommand that abort an in-progress unshelve"""
-    with repo.lock():
+    if opts.get('no_backup'):
+        raise error.Abort(_("unshelve does not support no-backup flag"))
+    if opts.get('dry_run'):
+        return 0
+    if not state:
+        statetuple = _loadshelvedstate(ui, repo, abortf=True, **opts)
+        state, opts = statetuple
+    with repo.wlock(), repo.lock():
         try:
             checkparents(repo, state)
 
@@ -864,31 +897,12 @@
         if abortf and opts.get('tool', False):
             ui.warn(_('tool option will be ignored\n'))
 
-        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
-            cmdutil.wrongtooltocontinue(repo, _('unshelve'))
-        except error.CorruptedState as err:
-            ui.debug(pycompat.bytestr(err) + '\n')
-            if continuef:
-                msg = _('corrupted shelved state file')
-                hint = _('please run hg unshelve --abort to abort unshelve '
-                         'operation')
-                raise error.Abort(msg, hint=hint)
-            elif abortf:
-                msg = _('could not read shelved state file, your working copy '
-                        'may be in an unexpected state\nplease update to some '
-                        'commit\n')
-                ui.warn(msg)
-                shelvedstate.clear(repo)
-            return
+        statetuple = _loadshelvedstate(ui, repo, continuef=continuef,
+                                       abortf=abortf, **opts)
+        state, opts = statetuple
 
         if abortf:
-            return unshelveabort(ui, repo, state, opts)
+            return unshelveabort(ui, repo, state)
         elif continuef:
             return unshelvecontinue(ui, repo, state, opts)
     elif len(shelved) > 1:
diff --git a/mercurial/state.py b/mercurial/state.py
--- a/mercurial/state.py
+++ b/mercurial/state.py
@@ -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"),
diff --git a/tests/test-shelve2.t b/tests/test-shelve2.t
--- a/tests/test-shelve2.t
+++ b/tests/test-shelve2.t
@@ -1,4 +1,4 @@
-#testcases stripbased phasebased
+#testcases stripbased phasebased abortflag abortcommand
 
   $ cat <<EOF >> $HGRCPATH
   > [extensions]
@@ -19,6 +19,13 @@
 
 #endif
 
+#if abortflag
+  $ cat >> $HGRCPATH <<EOF
+  > [alias]
+  > abort = unshelve --abort
+  > EOF
+#endif
+
 shelve should leave dirstate clean (issue4055)
 
   $ hg init shelverebase
@@ -285,7 +292,25 @@
   >>>>>>> working-copy: aef214a5229c - shelve: changes to: commit stuff
   $ cat f.orig
   g
-  $ hg unshelve --abort
+
+#if abortcommand
+when in dry-run mode
+  $ hg abort --dry-run
+  aborting unshelve
+
+when in no-backup mode
+  $ hg abort --no-backup
+  abort: unshelve does not support no-backup flag
+  [255]
+
+when dry-run mode is used with no backup
+  $ hg abort --dry-run --no-backup
+  aborting unshelve
+  abort: unshelve does not support no-backup flag
+  [255]
+#endif
+
+  $ hg abort
   unshelve of 'default' aborted
   $ hg st
   ? f.orig
@@ -695,14 +720,20 @@
   [255]
 
 Unshelve --abort works with a corrupted shelvedstate
-  $ hg unshelve --abort
+  $ hg abort
   could not read shelved state file, your working copy may be in an unexpected state
   please update to some commit
 
 Unshelve --abort fails with appropriate message if there's no unshelve in
 progress
-  $ hg unshelve --abort
-  abort: no unshelve in progress
+  $ hg abort
+  abort: no unshelve in progress (abortflag !)
+  abort: merge does not support 'hg abort' (abortcommand !)
+  (use 'hg commit' or 'hg merge --abort') (abortcommand !)
+  abort: merge does not support 'hg abort' (phasebased !)
+  (use 'hg commit' or 'hg merge --abort') (phasebased !)
+  abort: merge does not support 'hg abort' (stripbased !)
+  (use 'hg commit' or 'hg merge --abort') (stripbased !)
   [255]
   $ cd ..
 
@@ -822,7 +853,7 @@
   warning: conflicts while merging a! (edit, then use 'hg resolve --mark')
   unresolved conflicts (see 'hg resolve', then 'hg unshelve --continue')
   [1]
-  $ hg unshelve --abort
+  $ hg abort
   unshelve of 'default' aborted
 
 Unshelve without .shelve metadata (can happen when upgrading a repository with old shelve)
@@ -841,7 +872,7 @@
   [1]
   $ cat .hg/shelved/default.shelve
   node=82e0cb9893247d12667017593ce1e5655860f1ac
-  $ hg unshelve --abort
+  $ hg abort
   unshelve of 'default' aborted
 
 #endif