grangertest: grangertest is simply a Wald test comparing the unrestricted model—in which y is explained by the lags (up to order order) of y and x—and the restricted model—in which y is only explained by the lags of y.
causality:Two causality tests are implemented. The first is a F-type Granger-causality test and the second is a Wald-type test that is characterized by testing for nonzero correlation between the error processes of the cause and effect variables.