diff --git a/mercurial/cmdutil.py b/mercurial/cmdutil.py
--- a/mercurial/cmdutil.py
+++ b/mercurial/cmdutil.py
@@ -11,6 +11,59 @@ import os, sys, mdiff, bdiff, util, temp
 
 revrangesep = ':'
 
+def runcommand(u, options, d):
+    # enter the debugger before command execution
+    if options['debugger']:
+        pdb.set_trace()
+
+    try:
+        try:
+            if options['profile']:
+                import hotshot, hotshot.stats
+                prof = hotshot.Profile("hg.prof")
+                try:
+                    try:
+                        return prof.runcall(d)
+                    except:
+                        try:
+                            u.warn(_('exception raised - generating '
+                                     'profile anyway\n'))
+                        except:
+                            pass
+                        raise
+                finally:
+                    prof.close()
+                    stats = hotshot.stats.load("hg.prof")
+                    stats.strip_dirs()
+                    stats.sort_stats('time', 'calls')
+                    stats.print_stats(40)
+            elif options['lsprof']:
+                try:
+                    from mercurial import lsprof
+                except ImportError:
+                    raise util.Abort(_(
+                        'lsprof not available - install from '
+                        'http://codespeak.net/svn/user/arigo/hack/misc/lsprof/'))
+                p = lsprof.Profiler()
+                p.enable(subcalls=True)
+                try:
+                    return d()
+                finally:
+                    p.disable()
+                    stats = lsprof.Stats(p.getstats())
+                    stats.sort()
+                    stats.pprint(top=10, file=sys.stderr, climit=5)
+            else:
+                return d()
+        finally:
+            u.flush()
+    except:
+        # enter the debugger when we hit an exception
+        if options['debugger']:
+            pdb.post_mortem(sys.exc_info()[2])
+        u.print_exc()
+        raise
+
 def parseurl(url, revs):
     '''parse url#branch, returning url, branch + revs'''