feat: add Level 3 signature freezing tests for reexport API

Add comprehensive tests to freeze API signatures across all reexport files:
- Type hierarchy checks for inheritance relationships
- Method signature checks with has() for key functions
- Missing symbols: solve and plot! now properly tested
- All 503 reexport tests passing

This will detect breakages when CTX packages change their APIs.

Files modified:
- test/suite/reexport/test_ctbase.jl: exception inheritance
- test/suite/reexport/test_ctdirect.jl: discretizer hierarchy + discretize signature
- test/suite/reexport/test_ctflows.jl: Hamiltonian types + Lift/Flow signatures
- test/suite/reexport/test_ctmodels.jl: plot! + OCP types + serialization signatures
- test/suite/reexport/test_ctsolvers.jl: solver/modeler/parameter hierarchy + DOCP signatures
- test/suite/reexport/test_optimalcontrol.jl: solve + methods signatures

Author: ocots

docs/src/api/private.md

@@ -38,6 +38,21 @@ function test_ctbase()
                 Test.@test T isa DataType
             end
         end
+
+        Test.@testset "Type Hierarchy" begin
+            Test.@testset "Exception inheritance" begin
+                for T in (
+                    OptimalControl.IncorrectArgument,
+                    OptimalControl.PreconditionError,
+                    OptimalControl.NotImplemented,
+                    OptimalControl.ParsingError,
+                    OptimalControl.AmbiguousDescription,
+                    OptimalControl.ExtensionError,
+                )
+                    Test.@test T <: OptimalControl.CTException
+                end
+            end
+        end
     end
 end
 

test/suite/reexport/test_ctbase.jl

@@ -29,6 +29,19 @@ function test_ctdirect()
             Test.@test isdefined(CurrentModule, :discretize)
             Test.@test discretize isa Function
         end
+
+        Test.@testset "Type Hierarchy" begin
+            Test.@test OptimalControl.Collocation <: OptimalControl.AbstractDiscretizer
+        end
+
+        Test.@testset "Method Signatures" begin
+            Test.@testset "discretize" begin
+                Test.@test hasmethod(
+                    discretize,
+                    Tuple{OptimalControl.AbstractModel,OptimalControl.AbstractDiscretizer},
+                )
+            end
+        end
     end
 end
 

test/suite/reexport/test_ctdirect.jl

@@ -9,6 +9,7 @@ module TestCtflows
 
 using Test: Test
 using OptimalControl # using is mandatory since we test exported symbols
+import CTFlows # needed for abstract type checks
 
 const VERBOSE = isdefined(Main, :TestOptions) ? Main.TestOptions.VERBOSE : true
 const SHOWTIMING = isdefined(Main, :TestOptions) ? Main.TestOptions.SHOWTIMING : true
@@ -45,6 +46,22 @@ function test_ctflows()
             Test.@test isdefined(OptimalControl, Symbol("@Lie"))
             Test.@test isdefined(CurrentModule, Symbol("@Lie"))
         end
+
+        Test.@testset "Type Hierarchy" begin
+            Test.@test OptimalControl.Hamiltonian <: CTFlows.AbstractHamiltonian
+            Test.@test OptimalControl.HamiltonianLift <: CTFlows.AbstractHamiltonian
+            Test.@test OptimalControl.HamiltonianVectorField <: CTFlows.AbstractVectorField
+        end
+
+        Test.@testset "Method Signatures" begin
+            Test.@testset "Lift" begin
+                Test.@test hasmethod(Lift, Tuple{CTFlows.VectorField})
+                Test.@test hasmethod(Lift, Tuple{Function})
+            end
+            Test.@testset "Flow" begin
+                Test.@test hasmethod(Flow, Tuple{Vararg{Any}})
+            end
+        end
     end
 end
 

test/suite/reexport/test_ctflows.jl

@@ -27,6 +27,9 @@ function test_ctmodels()
             Test.@test isdefined(OptimalControl, :plot)
             Test.@test isdefined(CurrentModule, :plot)
             Test.@test plot isa Function
+            Test.@test isdefined(OptimalControl, :plot!)
+            Test.@test isdefined(CurrentModule, :plot!)
+            Test.@test plot! isa Function
         end
 
         Test.@testset "Initial Guess Types" begin
@@ -184,6 +187,25 @@ function test_ctmodels()
                 end
             end
         end
+
+        Test.@testset "Type Hierarchy" begin
+            Test.@test OptimalControl.Model <: OptimalControl.AbstractModel
+            Test.@test OptimalControl.Solution <: OptimalControl.AbstractSolution
+            Test.@test OptimalControl.InitialGuess <: OptimalControl.AbstractInitialGuess
+        end
+
+        Test.@testset "Method Signatures" begin
+            Test.@testset "export_ocp_solution" begin
+                Test.@test hasmethod(
+                    export_ocp_solution, Tuple{OptimalControl.AbstractSolution}
+                )
+            end
+            Test.@testset "import_ocp_solution" begin
+                Test.@test hasmethod(
+                    import_ocp_solution, Tuple{OptimalControl.AbstractModel}
+                )
+            end
+        end
     end
 end
 

test/suite/reexport/test_ctmodels.jl

@@ -10,6 +10,7 @@ module TestCtsolvers
 using Test: Test
 using CTSolvers: CTSolvers
 using OptimalControl # using is mandatory since we test exported symbols
+import SolverCore # needed for ocp_solution signature check
 
 const VERBOSE = isdefined(Main, :TestOptions) ? Main.TestOptions.VERBOSE : true
 const SHOWTIMING = isdefined(Main, :TestOptions) ? Main.TestOptions.SHOWTIMING : true
@@ -155,6 +156,52 @@ function test_ctsolvers()
             Test.@test !isdefined(OptimalControl, :get_parameter_type)
             Test.@test !isdefined(OptimalControl, :available_parameters)
         end
+
+        Test.@testset "Type Hierarchy" begin
+            Test.@testset "Modelers" begin
+                Test.@test OptimalControl.ADNLP <: OptimalControl.AbstractNLPModeler
+                Test.@test OptimalControl.Exa <: OptimalControl.AbstractNLPModeler
+            end
+            Test.@testset "Solvers" begin
+                Test.@test OptimalControl.Ipopt <: OptimalControl.AbstractNLPSolver
+                Test.@test OptimalControl.MadNLP <: OptimalControl.AbstractNLPSolver
+                Test.@test OptimalControl.MadNCL <: OptimalControl.AbstractNLPSolver
+                Test.@test OptimalControl.Knitro <: OptimalControl.AbstractNLPSolver
+            end
+            Test.@testset "Parameters" begin
+                Test.@test OptimalControl.CPU <: CTSolvers.AbstractStrategyParameter
+                Test.@test OptimalControl.GPU <: CTSolvers.AbstractStrategyParameter
+            end
+        end
+
+        Test.@testset "Method Signatures" begin
+            Test.@testset "ocp_model" begin
+                Test.@test hasmethod(ocp_model, Tuple{OptimalControl.DiscretizedModel})
+            end
+            Test.@testset "nlp_model" begin
+                Test.@test hasmethod(
+                    nlp_model,
+                    Tuple{
+                        OptimalControl.DiscretizedModel,
+                        Any,
+                        OptimalControl.AbstractNLPModeler,
+                    },
+                )
+            end
+            Test.@testset "ocp_solution" begin
+                Test.@test hasmethod(
+                    ocp_solution,
+                    Tuple{
+                        OptimalControl.DiscretizedModel,
+                        SolverCore.AbstractExecutionStats,
+                        OptimalControl.AbstractNLPModeler,
+                    },
+                )
+            end
+            Test.@testset "describe" begin
+                Test.@test hasmethod(describe, Tuple{Symbol})
+            end
+        end
     end
 end