Merge pull request #1574 from SciML/myb/hash

Define hash for SymbolicContinuousCallback

Author: YingboMa

src/systems/abstractsystem.jl

@@ -171,6 +171,10 @@ end
 
 Base.:(==)(e1::SymbolicContinuousCallback, e2::SymbolicContinuousCallback) = isequal(e1.eqs, e2.eqs) && isequal(e1.affect, e2.affect)
 Base.isempty(cb::SymbolicContinuousCallback) = isempty(cb.eqs)
+function Base.hash(cb::SymbolicContinuousCallback, s::UInt)
+    s = foldr(hash, cb.eqs, init=s)
+    foldr(hash, cb.affect, init=s)
+end
 
 to_equation_vector(eq::Equation) = [eq]
 to_equation_vector(eqs::Vector{Equation}) = eqs

test/odesystem.jl

@@ -19,6 +19,7 @@ eqs = [D(x) ~ σ*(y-x),
 ModelingToolkit.toexpr.(eqs)[1]
 @named de = ODESystem(eqs; defaults=Dict(x => 1))
 @test eval(toexpr(de)) == de
+@test hash(deepcopy(de)) == hash(de)
 
 generate_function(de)