Fix QUBOTools.varshow(::VI)

ext/QUBOTools_MOI/num_reads.jl

@@ -11,8 +11,6 @@ struct NumberOfReads <: MOI.AbstractModelAttribute
     end
 end
 
-QUBOTools.__moi_num_reads() = NumberOfReads
-
 function MOI.is_set_by_optimize(::NumberOfReads)
     return true
 end
@@ -28,3 +26,10 @@ function MOI.get(model::MOI.ModelLike, attr::NumberOfReads)
     # will not account for solution multiplicity.
     return 1
 end
+
+# The function takes no arguments and returns the NumberOfReads type.
+# Other packages will assign its return value to a constant, e.g.,
+#
+#     const NumberOfReads = QUBOTools.__moi_num_reads()
+#
+QUBOTools.__moi_num_reads() = NumberOfReads

ext/QUBOTools_MOI/qubo_model.jl

@@ -15,13 +15,6 @@ mutable struct QUBOModel{T,C<:BinaryDomain} <: MOI.ModelLike
     end
 end
 
-# The function takes no arguments and returns the QUBOModel type. Other
-# packages will assign its return value to a constant, e.g.,
-#
-#     const QUBOModel = QUBOTools.__moi_qubo_model()
-#
-QUBOTools.__moi_qubo_model() = QUBOModel
-
 function QUBOModel{T}() where {T}
     return QUBOModel{T,MOI.ZeroOne}()
 end
@@ -160,3 +153,10 @@ function MOI.get(::QUBOModel{T,C}, ::MOI.VariableName, vi::VI) where {T,C<:Binar
         return "s[$(vi.value)]"
     end
 end
+
+# The function takes no arguments and returns the QUBOModel type.
+# Other packages will assign its return value to a constant, e.g.,
+#
+#     const QUBOModel = QUBOTools.__moi_qubo_model()
+#
+QUBOTools.__moi_qubo_model() = QUBOModel

ext/QUBOTools_MOI/spin_set.jl

@@ -5,6 +5,14 @@ The set ``\left\lbrace{}{\pm 1}\right\rbrace{}``.
 """
 struct Spin <: MOI.AbstractScalarSet end
 
+function MOIU._to_string(options::MOIU._PrintOptions, ::Spin)
+    return string(MOIU._to_string(options, ∈), " {±1}")
+end
+
+function MOIU._to_string(::MOIU._PrintOptions{MIME"text/latex"}, ::Spin)
+    return raw"\in \left\lbrace{}{\pm 1}\right\rbrace{}"
+end
+
 # Since extensions do not allow new types to be defined and exported (only
 # methods), we can still provide a type by first defining an empty function
 # and then defining an "argless" method to retrive it, requiring that the
@@ -13,11 +21,3 @@ struct Spin <: MOI.AbstractScalarSet end
 #     const Spin = QUBOTools.__moi_spin_set()
 #
 QUBOTools.__moi_spin_set() = Spin
-
-function MOIU._to_string(options::MOIU._PrintOptions, ::Spin)
-    return string(MOIU._to_string(options, ∈), " {±1}")
-end
-
-function MOIU._to_string(::MOIU._PrintOptions{MIME"text/latex"}, ::Spin)
-    return raw"\in \left\lbrace{}{\pm 1}\right\rbrace{}"
-end

ext/QUBOTools_MOI/variables.jl

@@ -1,4 +1,4 @@
 # This will fall back to the integer ordering method.
 QUBOTools.varlt(u::VI, v::VI) = QUBOTools.varlt(u.value, v.value)
 
-QUBOTools.varshow(io::IO, v::VI) = QUBOTools.varshow(io, v.value)
+QUBOTools.varshow(v::VI) = QUBOTools.varshow(v.value)

test/integration/ext/moi.jl

@@ -14,14 +14,21 @@ function test_moi_variables()
         # Check if the Spin variable set is defined
         @test QUBOTools.__moi_spin_set() === Spin
 
-        # Check if the variable ordering of variables is behaving accordingly
-        @test QUBOTools.varlt(VI(1), VI(1)) === false
-        @test QUBOTools.varlt(VI(1), VI(2)) === true
-        @test QUBOTools.varlt(VI(2), VI(1)) === false
-
-        # This specific ordering follows as 1, 2, 3, ..., -1, -2, -3, ...
-        @test QUBOTools.varlt(VI(1), VI(-1)) === true
-        @test QUBOTools.varlt(VI(-1), VI(1)) === false
+        @testset "→ varlt" begin
+            # Check if the variable ordering of variables is behaving accordingly
+            @test QUBOTools.varlt(VI(1), VI(1)) === false
+            @test QUBOTools.varlt(VI(1), VI(2)) === true
+            @test QUBOTools.varlt(VI(2), VI(1)) === false
+
+            # This specific ordering follows as 1, 2, 3, ..., -1, -2, -3, ...
+            @test QUBOTools.varlt(VI(1), VI(-1)) === true
+            @test QUBOTools.varlt(VI(-1), VI(1)) === false
+        end
+
+        @testset "→ varshow" begin
+            @test QUBOTools.varshow(VI(103)) == "x₁₀₃"
+            @test QUBOTools.varshow(VI(-13)) == "x₋₁₃"
+        end
     end
 
     return nothing