194 # list of steps to perform discovery before push

   195 pushdiscoveryorder = []

   196 

   197 # Mapping between step name and function

   198 #

   199 # This exists to help extensions wrap steps if necessary

   200 pushdiscoverymapping = {}

   201 

   202 def pushdiscovery(stepname):

   203     """decorator for function performing discovery before push

   204 

   205     The function is added to the step -> function mapping and appended to the

   206     list of steps.  Beware that decorated function will be added in order (this

   207     may matter).

   208 

   209     You can only use this decorator for a new step, if you want to wrap a step

   210     from an extension, change the pushdiscovery dictionary directly."""

   211     def dec(func):

   212         assert stepname not in pushdiscoverymapping

   213         pushdiscoverymapping[stepname] = func

   214         pushdiscoveryorder.append(stepname)

   215         return func

   216     return dec

   217 

   218 

   219