func (s *CommonProvisionerSuite) waitHardwareCharacteristics(c *gc.C, m *state.Machine, check func() bool) {
w := m.WatchHardwareCharacteristics()
defer stop(c, w)
timeout := time.After(coretesting.LongWait)
resync := time.After(0)
for {
select {
case <-w.Changes():
if check() {
return
}
case <-resync:
resync = time.After(coretesting.ShortWait)
s.BackingState.StartSync()
case <-timeout:
c.Fatalf("hardware characteristics for machine %v wait timed out", m)
}
}
}