Add tests for model display

src/library/model/abstract.jl

@@ -91,16 +91,14 @@ function description(model::AbstractModel)
 end
 
 # ~*~ I/O ~*~ #
-function Base.copy!(target::X, source::Y) where {X<:AbstractModel,Y<:AbstractModel}
-    return copy!(target, convert(X, source))
-end
-
 function Base.show(io::IO, model::AbstractModel)
     if isempty(model)
-        println(
+        print(
             io,
             """
-            QUBOTools Model [$(sense(model)), $(domain(model))]
+            QUBOTools Model
+            ▷ Sense ………………… $(sense(model))
+            ▷ Domain ……………… $(domain(model))
 
             The model is empty.
             """,
@@ -111,8 +109,10 @@ function Base.show(io::IO, model::AbstractModel)
         println(
             io,
             """
-            QUBOTools Model [$(sense(model)), $(domain(model))]
-            ▷ Variables ……… $(dimension(model))  
+            QUBOTools Model
+            ▷ Sense ………………… $(sense(model))
+            ▷ Domain ……………… $(domain(model))
+            ▷ Variables ……… $(dimension(model))
 
             Density:
             ▷ Linear ……………… $(Printf.@sprintf("%6.2f", 100.0 * linear_density(model)))%

test/unit/library/model.jl

@@ -133,6 +133,12 @@ function test_model(V = Symbol, T = Float64, U = Int)
                     8 => 0,
                 )
             end
+
+            @testset "Metrics" begin
+                @test QUBOTools.linear_density(model)    ≈ 4/8   # l / n
+                @test QUBOTools.quadratic_density(model) ≈ 10/56 # 2q / (n² - n)
+                @test QUBOTools.density(model)           ≈ 14/64 # (l + 2q) / n²
+            end
         end
 
         model_copy = copy(model)
@@ -151,6 +157,45 @@ function test_model(V = Symbol, T = Float64, U = Int)
 
             @test _compare_models(model, model_copy; compare_solutions = true)
         end
+
+        @testset "⋅ Print" begin
+            let io = IOBuffer()
+                print(io, model)
+
+                @test String(take!(io)) == """
+                    QUBOTools Model
+                    ▷ Sense ………………… Max
+                    ▷ Domain ……………… SpinDomain
+                    ▷ Variables ……… 8
+                    
+                    Density:
+                    ▷ Linear ………………  50.00%
+                    ▷ Quadratic ………  17.86%
+                    ▷ Total …………………  21.88%
+                    
+                    Warm-start:
+                    ▷ Sites ………………… 8/8
+                    
+                    Solutions:
+                    ▷ Samples …………… 4
+                    ▷ Best value …… 4.0
+                    """
+            end
+
+            empty_model = QUBOTools.Model{V,T,U}(; sense = :min, domain = :bool)
+
+            let io = IOBuffer()
+                print(io, empty_model)
+
+                @test String(take!(io)) == """
+                    QUBOTools Model
+                    ▷ Sense ………………… Min
+                    ▷ Domain ……………… BoolDomain
+                    
+                    The model is empty.
+                    """
+            end
+        end
     end
 
     return nothing