Test default behavior of type utils

Author: MilesCranmer

test/unittests.jl

@@ -519,6 +519,13 @@ end
     @test typeof(MyDimensions(1, 1, 1)) == MyDimensions{Int}
     @test typeof(MyDimensions{Float64}(1, 1, 1)) == MyDimensions{Float64}
 
+    # Can use the default constructorof, with_type_parameters, and dimension_names:
+    @test DynamicQuantities.constructorof(MyDimensions{Float64}) == MyDimensions
+    @test DynamicQuantities.constructorof(MyQuantity{Float64}) == MyQuantity
+    @test DynamicQuantities.with_type_parameters(MyDimensions{Float64}, Rational{Int}) == MyDimensions{Rational{Int}}
+    @test DynamicQuantities.with_type_parameters(MyQuantity{Float64,DEFAULT_DIM_TYPE}, Float32, MyDimensions{Float64}) == MyQuantity{Float32,MyDimensions{Float64}}
+    @test DynamicQuantities.dimension_names(MyDimensions{Float64}) == (:length, :mass, :time)
+
     # But, we always need to use a quantity when mixing with mathematical operations:
     @test_throws ErrorException MyQuantity(0.1) + 0.1 * MyDimensions()
 end
@@ -625,6 +632,7 @@ end
     y = 0.5us"km/s"
     qa = [x, y]
     @test qa isa Vector{Quantity{Float64,SymbolicDimensions{Rational{Int}}}}
+    DynamicQuantities.with_type_parameters(SymbolicDimensions{Float64}, Rational{Int}) == SymbolicDimensions{Rational{Int}}
 end
 
 @testset "uconvert" begin