isone for IsingBimodule (#21)

* get `isone` to return true or false for `IsingBimodule`

* test `isone`

* remove comment oops

* remove boolean comparisons

Author: borisdevos

src/multifusion.jl

@@ -85,6 +85,8 @@ function Base.one(a::IsingBimodule)
     return IsingBimodule(a.row, a.col, 0)
 end
 
+Base.isone(a::IsingBimodule) = leftone(a) == a == rightone(a)
+
 function Base.one(::Type{IsingBimodule})
     throw(ArgumentError("one of Type IsingBimodule doesn't exist"))
 end

test/multifusion.jl

@@ -23,6 +23,10 @@ Istr = TensorKitSectors.type_repr(I)
         @test one(C1) == leftone(M) == rightone(Mop)
         @test one(D1) == rightone(M) == leftone(Mop)
 
+        @test @constinferred(isone(C0))
+        @test isone(D0)
+        @test !isone(C1) && !isone(D1) && !isone(M) && !isone(Mop)
+
         @test eval(Meta.parse(sprint(show, s))) == s
         @test @constinferred(hash(s)) == hash(deepcopy(s))
         @constinferred dual(s)