fixed tests

Author: rittermarc

src/contraction.jl

@@ -324,7 +324,7 @@ function contract_naive(
     tolerance=0.0, maxbonddim=typemax(Int)
 )::TensorTrain{T,4} where {T}
     if obj.f isa Function
-        error("Cannot contract matrix product with a function.")
+        error("Naive contraction implementation cannot contract matrix product with a function. Use algorithm=:TCI instead.")
     end
 
     a, b = obj.mpo
@@ -436,6 +436,9 @@ function contract(
     if algorithm === :TCI
         return contract_TCI(A, B; tolerance=tolerance, maxbonddim=maxbonddim, f=f, kwargs...)
     elseif algorithm === :naive
+        if f !== nothing
+            error("Naive contraction implementation cannot contract matrix product with a function. Use algorithm=:TCI instead.")
+        end
         return contract_naive(A, B; tolerance=tolerance, maxbonddim=maxbonddim)
     else
         throw(ArgumentError("Unknown algorithm $algorithm."))

test/test_contraction.jl

@@ -22,7 +22,7 @@ end
     @test vec(reshape(permutedims(a, (2, 1, 3)), 3, :) * reshape(permutedims(b, (1, 3, 2)), :, 5)) ≈ vec(ab)
 end
 
-@testset "MPO-MPO contraction" for f in [nothing, x -> 2 * x], algorithm in ["TCI", "naive"]
+@testset "MPO-MPO contraction" for f in [nothing, x -> 2 * x], algorithm in [:TCI, :naive]
     N = 4
     bonddims_a = [1, 2, 3, 2, 1]
     bonddims_b = [1, 2, 3, 2, 1]
@@ -39,7 +39,9 @@ end
         for n = 1:N
     ])
 
-    if f === nothing || algorithm != "naive"
+    if f !== nothing && algorithm === :naive
+        @test_throws ErrorException contract(a, b; f=f, algorithm=algorithm)
+    else
         ab = contract(a, b; f=f, algorithm=algorithm)
         @test sitedims(ab) == [[localdims1[i], localdims3[i]] for i = 1:N]
         if f === nothing