diff --git a/mercurial/statecheck.py b/mercurial/statecheck.py
new file mode 100644
--- /dev/null
+++ b/mercurial/statecheck.py
@@ -0,0 +1,71 @@
+from __future__ import absolute_import
+
+from .i18n import _
+
+from . import (
+    error,
+    util,
+)
+
+class statecheck(object):
+    """a utility class that will to deal with multistep operations
+       like graft, histedit, bisect, update etc and check whether such commands
+       are in an unfinished conditition of not and return appropriate message
+       and hint.
+       It also has the ability to register and determine the states of any new
+       multistep operation or multistep command extension.
+    """
+
+    def __init__(self, cmdname, fname, clearable=False, allowcommit=False,
+                 stopflag=False):
+        """cmdname is the name the command
+
+        fname is the file name in which data should be stored in .hg directory.
+        It is None for merge command.
+
+        clearable boolean determines whether or not interrupted states can be
+        cleared by running `hg update -C .`
+
+        allowcommit boolean decides whether commit is allowed during interrupted
+        state or not.
+
+        stopflag is a boolean that determines whether or not a command supports
+        --stop flag
+
+        """
+        self._cmdname = cmdname
+        self._fname = fname
+        self._clearable = clearable
+        self._allowcommit = allowcommit
+        self._stopflag = stopflag
+
+    def _hintmessage(self):
+        """returns the hint message corresponding to the command"""
+        if self._cmdname == 'bisect':
+            msg = _('To mark the changeset good:    hg bisect --good\n'
+                    'To mark the changeset bad:     hg bisect --bad\n'
+                    'To abort:                      hg bisect --reset\n')
+
+        elif self._cmdname == 'update':
+            msg = _("use 'hg update' to get a consistent checkout")
+
+        else:
+            msg = (_('To continue:    hg %s --continue\n'
+                    'To abort:       hg %s --abort') % (self._cmdname,
+                    self._cmdname))
+            if self._stopflag:
+                msg = msg + (_('\nTo stop:        hg %s --stop') %
+                     (self._cmdname))
+        return msg
+
+    def _statusmessage(self):
+        """returns the status message corresponding to the command"""
+        if self._cmdname == 'update':
+            hint = _('last update was interrupted')
+        else:
+            hint = _('%s in progress') % (self._cmdname)
+        return hint
+
+    def _mergepredicate(self, repo):
+        """determines is a merge is in progress or not"""
+        return len(repo[None].parents()) > 1