Computing p-adic logarithm with precision two

Is the following conjectured algorithm for computing p-adic log
with precision two the same as pari's?

{
plog(p,B)=
/*p-adic logarithm with precision 2*/
local(a);
a=lift(Mod(B,p^2)^(p-1)-1)/p;\\Fermat quotient
if(a==0,return(0));
return(p*(p-a));
}