fix: fix array variables in mtkmodel

src/ModelingToolkit.jl

@@ -72,7 +72,7 @@ import Symbolics: rename, get_variables!, _solve, hessian_sparsity,
                   ParallelForm, SerialForm, MultithreadedForm, build_function,
                   rhss, lhss, prettify_expr, gradient,
                   jacobian, hessian, derivative, sparsejacobian, sparsehessian,
-                  substituter, scalarize, getparent, hasderiv, hasdiff
+                  substituter, scalarize, getparent, hasderiv, hasdiff, Arr
 
 import DiffEqBase: @add_kwonly
 export independent_variables, unknowns, parameters, full_parameters, continuous_events,

src/systems/abstractsystem.jl

@@ -1112,6 +1112,7 @@ end
 
 apply_to_variables(f::F, ex) where {F} = _apply_to_variables(f, ex)
 apply_to_variables(f::F, ex::Num) where {F} = wrap(_apply_to_variables(f, unwrap(ex)))
+apply_to_variables(f::F, ex::Arr) where {F} = wrap(_apply_to_variables(f, unwrap(ex)))
 function _apply_to_variables(f::F, ex) where {F}
     if isvariable(ex)
         return f(ex)

src/systems/model_parsing.jl

@@ -714,7 +714,7 @@ function parse_variable_arg(dict, mod, arg, varclass, kwargs, where_types)
     end
 
     push!(varexpr.args, metadata_expr)
-    return vv isa Num ? name : :($name...), varexpr
+    return name, varexpr
 end
 
 function handle_conditional_vars!(

test/model_parsing.jl

@@ -3,6 +3,7 @@ using ModelingToolkit: get_connector_type, get_defaults, get_gui_metadata,
                        get_systems, get_ps, getdefault, getname, readable_code,
                        scalarize, symtype, VariableDescription, RegularConnector,
                        get_unit
+using SymbolicIndexingInterface
 using URIs: URI
 using Distributions
 using DynamicQuantities, OrdinaryDiffEq
@@ -245,7 +246,7 @@ end
     kval = 5
     @named model = MockModel(; b2 = [1, 3], kval, cval = 1, func = identity)
 
-    @test lastindex(parameters(model)) == 31
+    @test lastindex(parameters(model)) == 21
 
     @test all(getdescription.([model.e2...]) .== "e2")
     @test all(getdescription.([model.h2...]) .== "h2(t)")
@@ -475,7 +476,7 @@ using ModelingToolkit: getdefault, scalarize
     @named model_with_component_array = ModelWithComponentArray()
 
     @test eval(ModelWithComponentArray.structure[:parameters][:r][:unit]) == eval(u"Ω")
-    @test lastindex(parameters(model_with_component_array)) == 3
+    @test lastindex(parameters(model_with_component_array)) == 1
 
     # Test the constant `k`. Manually k's value should be kept in sync here
     # and the ModelParsingPrecompile.
@@ -876,3 +877,26 @@ end
         end),
         false)
 end
+
+@testset "Array parameters and subcomponent defaults" begin
+    @mtkmodel Foo begin
+        @parameters begin
+            p[1:3]
+        end
+    end
+    @mtkmodel Bar begin
+        @parameters begin
+            q[1:3]
+        end
+        @components begin
+            foo = Foo(p = q)
+        end
+    end
+    @named model = Bar()
+    model = complete(model)
+    # non-scalarized versions are parameters
+    @test is_parameter(model, model.q)
+    @test is_parameter(model, model.foo.p)
+    # default is correctly (not) namespaced
+    @test isequal(ModelingToolkit.defaults(model)[model.foo.p], model.q)
+end