test: units passed to diff2term

test/downstream/Project.toml

@@ -1,6 +1,8 @@
 [deps]
 ModelingToolkit = "961ee093-0014-501f-94e3-6117800e7a78"
 ParameterizedFunctions = "65888b18-ceab-5e60-b2b9-181511a3b968"
+Symbolics = "0c5d862f-8b57-4792-8d23-62f2024744c7"
+Unitful = "1986cc42-f94f-5a68-af5c-568840ba703d"
 
 [compat]
 ModelingToolkit = "8.33, 9"

test/downstream/modeling_toolkit_utils.jl

@@ -0,0 +1,28 @@
+using Symbolics: diff2term
+using ModelingToolkit
+using ModelingToolkit: equivalent, get_unit, value, VariableUnit
+using Unitful: @u_str
+using Test
+
+@variables t [unit = u"s"] k(t)
+D = Differential(t)
+
+@test equivalent(
+    u"1/s",
+    get_unit(
+        diff2term(
+            value(D(k)),
+            Dict(VariableUnit => get_unit(D(k)))
+        )
+    )
+)
+
+@test equivalent(
+    u"1/s^2",
+    get_unit(
+        diff2term(
+            value(D(D(k))),
+            Dict(VariableUnit => get_unit(D(D(k))))
+        )
+    )
+)

test/runtests.jl

@@ -68,7 +68,8 @@ if GROUP == "All" || GROUP == "Core" || GROUP == "SymbolicIndexingInterface"
     end
 end
 
-if GROUP == "Downstream"
+if GROUP == "All" || GROUP == "Downstream"
     activate_downstream_env()
     #@time @safetestset "ParameterizedFunctions MATLABDiffEq Regression Test" begin include("downstream/ParameterizedFunctions_MATLAB.jl") end
+    @safetestset "ModelingToolkit Variable Utils Test" begin include("downstream/modeling_toolkit_utils.jl") end
 end