42     class progressui(ui.__class__):

    39     if ui.config('progress', 'disable', None) is None:

    43         _progbar = None

    40         ui.setconfig('progress', 'disable', 'False', 'hgext-progress')

    44 

    45         def _quiet(self):

    46             return self.debugflag or self.quiet

    47 

    48         def progress(self, *args, **opts):

    49             if not self._quiet():

    50                 self._progbar.progress(*args, **opts)

    51             return super(progressui, self).progress(*args, **opts)

    52 

    53         def write(self, *args, **opts):

    54             if not self._quiet() and self._progbar.printed:

    55                 self._progbar.clear()

    56             return super(progressui, self).write(*args, **opts)

    57 

    58         def write_err(self, *args, **opts):

    59             if not self._quiet() and self._progbar.printed:

    60                 self._progbar.clear()

    61             return super(progressui, self).write_err(*args, **opts)

    62 

    63     # Apps that derive a class from ui.ui() can use

    64     # setconfig('progress', 'disable', 'True') to disable this extension

    65     if ui.configbool('progress', 'disable'):

    66         return

    67     if progress.shouldprint(ui) and not ui.debugflag and not ui.quiet:

    68         dval = object()

    69         if getattr(ui, '_progbar', dval) is dval:

    70             ui.__class__ = progressui

    71             # we instantiate one globally-shared progress bar to avoid

    72             # competing progress bars when multiple UI objects get created

    73             if not progressui._progbar:

    74                 progressui._progbar = uimod.getprogbar(ui)