Model building fails when using @extend multiple times #3578
Description
The bug 🐞
When building a system that is an extension of an extended model MTK throws a MethodError.
Note that the model which is a single extension builds successfully.
Expected behavior
MTK should be able to build models that have been extended (with @extend) multiple times.
Minimal Reproducible Example 👇
using ModelingToolkit
using ModelingToolkit: t_nounits as t
@connector Port begin
T(t)
m_dot(t), [connect = Flow]
end
@mtkmodel Element1P begin
@components begin
port = Port()
end
@variables begin
m_dot(t)
end
@equations begin
m_dot ~ port.m_dot
end
end
@mtkmodel ExtendedElement1P begin
@extend Element1P()
# There could be more components, parameters, variables and/or equations here.
end
@named ext_system = ExtendedElement1P()
# Builds model without a problem.
@mtkmodel TwiceExtendedSystem begin
@extend ExtendedElement1P()
# There could be even more components, parameters, variables and/or equations here.
end
# However, if an extended system is extended again the model building fails:
@named twice_ext_system = TwiceExtendedSystem()
Error & Stacktrace
ERROR: MethodError: no method matching __ExtendedElement1P__(; name::Symbol, port::ModelingToolkit.NoValue, m_dot::ModelingToolkit.NoValue)
This error has been manually thrown, explicitly, so the method may exist but be intentionally marked as unimplemented.
Closest candidates are:
__ExtendedElement1P__(; name, m_dot) got unsupported keyword argument "port"
@ Main C:\Users\ZalánZsiborás\.julia\packages\ModelingToolkit\15RQb\src\systems\model_parsing.jl:151
Stacktrace:
[1] kwerr(kw::@NamedTuple{name::Symbol, port::ModelingToolkit.NoValue, m_dot::ModelingToolkit.NoValue}, args::Function)
@ Base .\error.jl:165
[2] (::ModelingToolkit.Model{…})(; kw::@Kwargs{…})
@ ModelingToolkit ~\.julia\packages\ModelingToolkit\15RQb\src\systems\model_parsing.jl:25
[3] __TwiceExtendedSystem__(; name::Symbol, port::ModelingToolkit.NoValue, m_dot::ModelingToolkit.NoValue)
@ Main ~\.julia\packages\ModelingToolkit\15RQb\src\systems\model_parsing.jl:151
[4] __TwiceExtendedSystem__
@ ~\.julia\packages\ModelingToolkit\15RQb\src\systems\model_parsing.jl:151 [inlined]
[5] #_#425
@ ~\.julia\packages\ModelingToolkit\15RQb\src\systems\model_parsing.jl:25 [inlined]
[6] top-level scope
@ ~\.julia\packages\ModelingToolkit\15RQb\src\systems\abstractsystem.jl:2272
Some type information was truncated. Use `show(err)` to see complete types.Environment:
Julia Version 1.11.5
ModelingToolkit v9.73.0