Run tests in R with non 0.5 underlying probabilities

I am trying to find out how to conduct run tests on one sample but with a non 0.5-0.5 underlying occurrence pattern of the two dichotomous values. For instance +++---++++ but assume that +'s had an underlying probability of 0.8 of happening whereas -'s had 0.2.

Is there an R function for a runs test which can address this?