feat: add name_to_symbolic

src/SymbolicIndexingInterface.jl

@@ -8,7 +8,8 @@ using Accessors: @reset
 RuntimeGeneratedFunctions.init(@__MODULE__)
 
 export ScalarSymbolic, ArraySymbolic, NotSymbolic, symbolic_type, hasname, getname,
-       Timeseries, NotTimeseries, is_timeseries, is_parameter_timeseries
+       Timeseries, NotTimeseries, is_timeseries, is_parameter_timeseries,
+       symbolic_evaluate
 include("trait.jl")
 
 export is_variable, variable_index, variable_symbols, is_parameter, parameter_index,
@@ -17,7 +18,7 @@ export is_variable, variable_index, variable_symbols, is_parameter, parameter_in
        is_observed, observed, parameter_observed, ParameterObservedFunction,
        is_time_dependent, constant_structure, symbolic_container,
        all_variable_symbols, all_symbols, solvedvariables, allvariables, default_values,
-       symbolic_evaluate
+       name_to_symbolic
 include("index_provider_interface.jl")
 
 export SymbolCache

src/index_provider_interface.jl

@@ -222,6 +222,25 @@ independent variables.
 """
 all_symbols(indp) = all_symbols(symbolic_container(indp))
 
+"""
+    name_to_symbolic(indp, sym::Symbol)
+
+Return the symbolic variable in `indp` with name `sym`. If there is no such variable,
+return `nothing`. This roughly corresponds to the reverse operation of [`getname`](@ref),
+in the context of index provider `indp`. By default, this method will search through
+`all_symbols(indp)` for one with the required name.
+
+See also: [`all_symbols`](@ref).
+"""
+function name_to_symbolic(indp, sym::Symbol)
+    for s in all_symbols(indp)
+        if hasname(s) && getname(s) == sym
+            return s
+        end
+    end
+    return nothing
+end
+
 """
     default_values(indp)
 

test/downstream/interface_tests.jl

@@ -0,0 +1,10 @@
+using ModelingToolkit
+using ModelingToolkit: t_nounits as t
+using SymbolicIndexingInterface
+
+@variables x(t)[1:2] y(t)
+@named sys = ODESystem(Equation[], t, [x, y], [])
+sys = complete(sys)
+
+@test isequal(name_to_symbolic(sys, :x), x)
+@test isequal(name_to_symbolic(sys, :y), y)

test/example_test.jl

@@ -90,6 +90,8 @@ sys = SystemMockup(true, [:x, :y, :z], [:a, :b, :c], :t)
 @test independent_variable_symbols(sys) == [:t]
 @test all_variable_symbols(sys) == [:x, :y, :z]
 @test sort(all_symbols(sys)) == [:a, :b, :c, :t, :x, :y, :z]
+@test name_to_symbolic.((sys,), all_symbols(sys)) == all_symbols(sys)
+@test name_to_symbolic(sys, :q) === nothing
 @test default_values(sys) == Dict() # fallback even if not implemented
 
 sys = SystemMockup(true, [:x, :y, :z], [:a, :b, :c], nothing)

test/runtests.jl

@@ -55,4 +55,10 @@ if GROUP == "All" || GROUP == "Downstream"
     @safetestset "BatchedInterface with array symbolics test" begin
         @time include("downstream/batchedinterface_arrayvars.jl")
     end
+    @safetestset "Remake with array symbolics test" begin
+        @time include("downstream/remake_arrayvars.jl")
+    end
+    @safetestset "MTK interface tests" begin
+        @time include("downstream/interface_tests.jl")
+    end
 end