diff mercurial/dispatch.py @ 29784:e3501546f7e4

profiling: add a context manager that no-ops if profiling isn't enabled

And refactor dispatch.py to use it. As you can see, the resulting code
is much simpler.

I was tempted to inline _runcommand as part of writing this series.
However, a number of extensions wrap _runcommand. So keeping it around
is necessary (extensions can't easily wrap runcommand because it calls
hooks before and after command execution).

--- a/mercurial/dispatch.py	Sun Aug 14 18:25:22 2016 -0700
+++ b/mercurial/dispatch.py	Sun Aug 14 17:51:12 2016 -0700
@@ -898,21 +898,12 @@
             repo.close()
 
 def _runcommand(ui, options, cmd, cmdfunc):
-    """Enables the profiler if applicable.
-
-    ``profiling.enabled`` - boolean config that enables or disables profiling
-    """
-    def checkargs():
+    """Run a command function, possibly with profiling enabled."""
+    with profiling.maybeprofile(ui):
         try:
             return cmdfunc()
         except error.SignatureError:
-            raise error.CommandError(cmd, _("invalid arguments"))
-
-    if ui.configbool('profiling', 'enabled'):
-        with profiling.profile(ui):
-            return checkargs()
-    else:
-        return checkargs()
+            raise error.CommandError(cmd, _('invalid arguments'))
 
 def _exceptionwarning(ui):
     """Produce a warning message for the current active exception"""