Parameterized FIFO in Chisel - riscv

Question

I was going through the Chisel 2.2 Tutorial manual (I am aware that Chisel3 is out in BETA version, but I am required to use Chisel2.2 for some extension of previously implemented modules).
I have been looking for examples of using DecoupledIO interface in Chisel and found a few in the tutorial mentioned above and also on StackOverflow.
One such example is Parameterized FIFO example in Chisel Tutorial manual whose implementation is:
class Fifo[T <: Data] (type: T, n: Int)extends Module {
val io = new Bundle {
val enq_val = Bool(INPUT)
val enq_rdy = Bool(OUTPUT)
val deq_val = Bool(OUTPUT)
val deq_rdy = Bool(INPUT)
val enq_dat = type.asInput
val deq_dat = type.asOutput
}
val enq_ptr= Reg(init = UInt(0, sizeof(n)))
val deq_ptr= Reg(init = UInt(0, sizeof(n)))
val is_full= Reg(init = Bool(false))
val do_enq= io.enq_rdy && io.enq_val
val do_deq= io.deq_rdy && io.deq_val
val is_empty= !is_full && (enq_ptr === deq_ptr)
val deq_ptr_inc = deq_ptr + UInt(1)
val enq_ptr_inc = enq_ptr + UInt(1)
val is_full_next = Mux(do_enq && ~do_deq &&(enq_ptr_inc===deq_ptr),Bool(true),Mux(do_deq && is_full, Bool(false), is_full))
enq_ptr := Mux(do_enq, enq_ptr_inc, enq_ptr)
deq_ptr := Mux(do_deq, deq_ptr_inc, deq_ptr)
is_full := is_full_next
val ram = Mem(n)
when (do_enq) {
ram(enq_ptr) := io.enq_dat
}
io.enq_rdy := !is_full
io.deq_val := !is_empty
ram(deq_ptr) <> io.deq_dat
}
I understand most of the implementation but the code snippet:
val is_full_next = Mux(do_enq && ~do_deq &&(enq_ptr_inc===deq_ptr),Bool(true),Mux(do_deq && is_full, Bool(false), is_full))
If I am interpreting it correctly we are trying to check if the next operation will lead to the condition of isFull or not. If it is so, why are we looking to check the value of enq_ptr_inc === deq_ptr.
If someone can share their view on how this might be working, I would like to hear from you.
Also, I am not sure if this is the simplest way to implement a parameterized FIFO. I am working on my own implementation, but if there is an easier way to implement a FIFO (not even a parameterized one), it would help me to clear my doubts.