fix: remove evals from model parsing

- Ensure that modules consisting MTKModels with component arrays and icons of
`Expr` type and `unit` metadata can be precompiled.

format/Project.toml

@@ -0,0 +1,2 @@
+[deps]
+JuliaFormatter = "98e50ef6-434e-11e9-1051-2b60c6c9e899"

src/systems/model_parsing.jl

@@ -178,15 +178,10 @@ function parse_variable_def!(dict, mod, arg, varclass, kwargs;
             (var, def)
         end
         Expr(:ref, a, b...) => begin
+            indices = map(i -> UnitRange(i.args[2], i.args[end]), b)
             parse_variable_def!(dict, mod, a, varclass, kwargs;
-                def, indices = [eval.(b)...])
+                def, indices)
         end
-        #= Expr(:if, condition, a) => begin
-        var, def = [], []
-            for var_def in a.args
-                parse_variable_def!(dict, mod, var_def, varclass, kwargs)
-            end
-        end =#
         _ => error("$arg cannot be parsed")
     end
 end
@@ -301,7 +296,7 @@ function parse_model!(exprs, comps, ext, eqs, icon, vs, ps, sps,
         parse_equations!(exprs, eqs, dict, body)
     elseif mname == Symbol("@icon")
         isassigned(icon) && error("This model has more than one icon.")
-        parse_icon!(icon, dict, body)
+        parse_icon!(body, dict, icon, mod)
     else
         error("$mname is not handled.")
     end
@@ -614,7 +609,7 @@ function parse_equations!(exprs, eqs, dict, body)
     end
 end
 
-function parse_icon!(icon, dict, body::String)
+function parse_icon!(body::String, dict, icon, mod)
     icon_dir = get(ENV, "MTK_ICONS_DIR", joinpath(DEPOT_PATH[1], "mtk_icons"))
     dict[:icon] = icon[] = if isfile(body)
         URI("file:///" * abspath(body))
@@ -633,8 +628,8 @@ function parse_icon!(icon, dict, body::String)
     end
 end
 
-function parse_icon!(icon, dict, body::Expr)
-    parse_icon!(icon, dict, eval(body))
+function parse_icon!(body::Symbol, dict, icon, mod)
+    parse_icon!(getfield(mod, body), dict, icon, mod)
 end
 
 ### Parsing Components:

test/model_parsing.jl

@@ -18,11 +18,12 @@ export Pin
     @icon "pin.png"
 end
 
+ground_logo = read(abspath(ENV["MTK_ICONS_DIR"], "ground.svg"), String)
 @mtkmodel Ground begin
     @components begin
         g = Pin()
     end
-    @icon read(abspath(ENV["MTK_ICONS_DIR"], "ground.svg"), String)
+    @icon ground_logo
     @equations begin
         g.v ~ 0
     end
@@ -164,8 +165,7 @@ resistor = getproperty(rc, :resistor; namespace = false)
 
 @test get_gui_metadata(rc.resistor).layout == Resistor.structure[:icon] ==
       read(joinpath(ENV["MTK_ICONS_DIR"], "resistor.svg"), String)
-@test get_gui_metadata(rc.ground).layout ==
-      read(abspath(ENV["MTK_ICONS_DIR"], "ground.svg"), String)
+@test get_gui_metadata(rc.ground).layout == read(abspath(ENV["MTK_ICONS_DIR"], "ground.svg"), String)
 @test get_gui_metadata(rc.capacitor).layout ==
       URI("https://upload.wikimedia.org/wikipedia/commons/7/78/Capacitor_symbol.svg")
 @test OnePort.structure[:icon] ==
@@ -321,6 +321,21 @@ end
     @test A.structure[:components] == [[:cc, :C]]
 end
 
+# Ensure that modules consisting MTKModels with component arrays and icons of
+# `Expr` type and `unit` metadata can be precompiled.
+@testset "Precompile packages with MTKModels" begin
+    push!(LOAD_PATH, joinpath(@__DIR__, "precompile_test"))
+
+    using ModelParsingPrecompile: ModelWithComponentArray
+
+    @named model_with_component_array = ModelWithComponentArray()
+
+    @test ModelWithComponentArray.structure[:parameters][:R][:unit] == u"Ω"
+    @test lastindex(parameters(model_with_component_array)) == 3
+
+    pop!(LOAD_PATH)
+end
+
 @testset "Conditional statements inside the blocks" begin
     @mtkmodel C begin end
 

test/precompile_test/ModelParsingPrecompile.jl

@@ -0,0 +1,12 @@
+module ModelParsingPrecompile
+
+using ModelingToolkit
+using Unitful
+
+@mtkmodel ModelWithComponentArray begin
+    @parameters begin
+        R(t)[1:3] = 1, [description = "Parameter array", unit = u"Ω"]
+    end
+end
+
+end