test: do not rely on system equality in tests

Author: AayushSabharwal

test/accessor_functions.jl

@@ -151,17 +151,11 @@ let
     # Checks `continuous_events_toplevel` and  `discrete_events_toplevel` (straightforward
     # as I stored the same single event in all systems). Don't check for non-toplevel cases as
     # technically not needed for these tests and name spacing the events is a mess.
-    bot_cev = ModelingToolkit.SymbolicContinuousCallback(
-        cevs[1], alg_eqs = [O ~ (d + p_bot) * X_bot + Y])
-    mid_dev = ModelingToolkit.SymbolicDiscreteCallback(
-        devs[1], alg_eqs = [O ~ (d + p_mid1) * X_mid1 + Y])
     @test all_sets_equal(
-        continuous_events_toplevel.([sys_bot, sys_bot_comp, sys_bot_ss])...,
-        [bot_cev])
+        continuous_events_toplevel.([sys_bot, sys_bot_comp, sys_bot_ss])...)
     @test all_sets_equal(
         discrete_events_toplevel.(
-            [sys_mid1, sys_mid1_comp, sys_mid1_ss])...,
-        [mid_dev])
+        [sys_mid1, sys_mid1_comp, sys_mid1_ss])...)
     @test all(sym_issubset(
                   continuous_events_toplevel(sys), get_continuous_events(sys))
     for sys in [sys_bot, sys_mid2, sys_mid1, sys_top])

test/analysis_points.jl

@@ -22,7 +22,7 @@ using Symbolics: NAMESPACE_SEPARATOR
     sys_normal = System(eqs, t, systems = [P, C], name = :hej)
     sys_normal2 = @test_nowarn expand_connections(sys_normal)
 
-    @test isequal(sys_ap2, sys_normal2)
+    @test issetequal(equations(sys_ap2), equations(sys_normal2))
 end
 
 @testset "Inverse causality throws a warning" begin

test/nonlinearsystem.jl

@@ -26,7 +26,10 @@ eqs = [0 ~ σ * (y - x) * h,
     0 ~ x * (ρ - z) - y,
     0 ~ x * y - β * z]
 @named ns = System(eqs, [x, y, z], [σ, ρ, β, h], defaults = Dict(x => 2))
-@test eval(toexpr(ns)) == ns
+ns2 = eval(toexpr(ns))
+@test issetequal(equations(ns), equations(ns2))
+@test issetequal(unknowns(ns), unknowns(ns2))
+@test issetequal(parameters(ns), parameters(ns2))
 test_nlsys_inference("standard", ns, (x, y, z), (σ, ρ, β, h))
 @test begin
     f = generate_rhs(ns, expression = Val{false})[2]

test/odesystem.jl

@@ -35,6 +35,10 @@ ssort(eqs) = sort(eqs, by = string)
 @named des[1:3] = System(eqs, t)
 @test length(unique(x -> ModelingToolkit.get_tag(x), des)) == 1
 
+de2 = eval(toexpr(de))
+@test issetequal(equations(de2), eqs)
+@test issetequal(unknowns(de2), unknowns(de))
+@test issetequal(parameters(de2), parameters(de))
 @test eval(toexpr(de)) == de
 @test hash(deepcopy(de)) == hash(de)
 
@@ -1427,33 +1431,6 @@ end
     @test_nowarn @named osys = System(eqs, t)
 end
 
-# Test `isequal`
-@testset "`isequal`" begin
-    @variables X(t)
-    @parameters p d(t)
-    eq = D(X) ~ p - d * X
-
-    osys1 = complete(System([eq], t; name = :osys))
-    osys2 = complete(System([eq], t; name = :osys))
-    @test osys1 == osys2 # true
-
-    continuous_events = [[X ~ 1.0] => [X ~ Pre(X) + 5.0]]
-    discrete_events = [SymbolicDiscreteCallback(
-        5.0 => [d ~ d / 2.0], discrete_parameters = [d])]
-
-    osys1 = complete(System([eq], t; name = :osys, continuous_events))
-    osys2 = complete(System([eq], t; name = :osys))
-    @test osys1 !== osys2
-
-    osys1 = complete(System([eq], t; name = :osys, discrete_events))
-    osys2 = complete(System([eq], t; name = :osys))
-    @test osys1 !== osys2
-
-    osys1 = complete(System([eq], t; name = :osys, continuous_events))
-    osys2 = complete(System([eq], t; name = :osys, discrete_events))
-    @test osys1 !== osys2
-end
-
 @testset "Constraint system construction" begin
     @variables x(..) y(..) z(..)
     @parameters a b c d e

test/sdesystem.jl

@@ -612,9 +612,8 @@ diffusion_eqs = [s*x 0
 
 sys2 = SDESystem(drift_eqs, diffusion_eqs, tt, sts, ps, name = :sys1)
 sys2 = complete(sys2)
-@set! sys1.parent = nothing
-@set! sys2.parent = nothing
-@test sys1 == sys2
+
+@test issetequal(ModelingToolkit.get_noise_eqs(sys1), ModelingToolkit.get_noise_eqs(sys2))
 
 prob = SDEProblem(sys1, [sts .=> [1.0, 0.0, 0.0]; ps .=> [10.0, 26.0]],
     (0.0, 100.0))
@@ -927,31 +926,6 @@ end
     end
 end
 
-@testset "SDESystem Equality with events" begin
-    @variables X(t)
-    @parameters p d
-    @brownian a
-    seq = D(X) ~ p - d * X + a
-    @mtkcompile ssys1 = System([seq], t; name = :ssys)
-    @mtkcompile ssys2 = System([seq], t; name = :ssys)
-    @test ssys1 == ssys2 # true
-
-    continuous_events = [[X ~ 1.0] => [X ~ Pre(X) + 5.0]]
-    discrete_events = [5.0 => [d ~ Pre(d) / 2.0]]
-
-    @mtkcompile ssys1 = System([seq], t; name = :ssys, continuous_events)
-    @mtkcompile ssys2 = System([seq], t; name = :ssys)
-    @test ssys1 !== ssys2
-
-    @mtkcompile ssys1 = System([seq], t; name = :ssys, discrete_events)
-    @mtkcompile ssys2 = System([seq], t; name = :ssys)
-    @test ssys1 !== ssys2
-
-    @mtkcompile ssys1 = System([seq], t; name = :ssys, continuous_events)
-    @mtkcompile ssys2 = System([seq], t; name = :ssys, discrete_events)
-    @test ssys1 !== ssys2
-end
-
 @testset "Error when constructing SDEProblem without `mtkcompile`" begin
     @parameters σ ρ β
     @variables x(tt) y(tt) z(tt)

test/serialization.jl

@@ -27,7 +27,10 @@ write(io, expand_connections(rc_model))
 str = String(take!(io))
 
 sys = include_string(@__MODULE__, str)
-@test sys == expand_connections(rc_model) # this actually kind of works, but the variables would have different identities.
+rc2 = expand_connections(rc_model)
+@test issetequal(equations(sys), equations(rc2))
+@test issetequal(unknowns(sys), unknowns(rc2))
+@test issetequal(parameters(sys), parameters(rc2))
 
 # check answer
 ss = mtkcompile(rc_model)

test/symbolic_events.jl

@@ -343,10 +343,11 @@ end
 
     cb = get_callback(prob)
     @test cb isa ModelingToolkit.DiffEqCallbacks.VectorContinuousCallback
-    @test getfield(ball, :continuous_events)[1] ==
-          SymbolicContinuousCallback(Equation[x ~ 0], Equation[vx ~ -Pre(vx)])
-    @test getfield(ball, :continuous_events)[2] ==
-          SymbolicContinuousCallback(Equation[y ~ -1.5, y ~ 1.5], Equation[vy ~ -Pre(vy)])
+    _cevs = getfield(ball, :continuous_events)
+    @test isequal(only(equations(_cevs[1])), x ~ 0)
+    @test isequal(only(observed(_cevs[1].affect.system)), vx ~ -Pre(vx))
+    @test issetequal(equations(_cevs[2]), [y ~ -1.5, y ~ 1.5])
+    @test isequal(only(observed(_cevs[2].affect.system)), vy ~ -Pre(vy))
     cond = cb.condition
     out = [0.0, 0.0, 0.0]
     p0 = 0.0