fix: canonicalize all positional args in @named

- So far, only the 1st positional-arg was canonicalized.
- Add relevant tests.

src/systems/abstractsystem.jl

@@ -964,7 +964,7 @@ function _named(name, call, runtime = false)
     if length(call.args) >= 2 && call.args[2] isa Expr
         # canonicalize to use `:parameters`
         if call.args[2].head === :kw
-            call.args[2] = Expr(:parameters, Expr(:kw, call.args[2].args...))
+            call = Expr(call.head, call.args[1], Expr(:parameters, call.args[2:end]...))
             has_kw = true
         elseif call.args[2].head === :parameters
             has_kw = true

test/direct.jl

@@ -2,6 +2,8 @@ using ModelingToolkit, StaticArrays, LinearAlgebra, SparseArrays
 using DiffEqBase
 using Test
 
+using ModelingToolkit: getdefault, getmetadata, SymScope
+
 canonequal(a, b) = isequal(simplify(a), simplify(b))
 
 # Calculus
@@ -271,3 +273,24 @@ end
 @parameters x [misc = "wow"]
 @test SymbolicUtils.getmetadata(Symbolics.unwrap(x), ModelingToolkit.VariableMisc,
     nothing) == "wow"
+
+# Scope of defaults in the systems generated by @named
+@mtkmodel MoreThanOneArg begin
+    @variables begin
+        x(t)
+        y(t)
+        z(t)
+    end
+end
+
+@parameters begin
+    l
+    m
+    n
+end
+
+@named model = MoreThanOneArg(x = l, y = m, z = n)
+
+@test getmetadata(getdefault(model.x), SymScope) == ParentScope(LocalScope())
+@test getmetadata(getdefault(model.y), SymScope) == ParentScope(LocalScope())
+@test getmetadata(getdefault(model.z), SymScope) == ParentScope(LocalScope())