How the library is tested, and which test file covers what. The file table in section 2 is a count of the TEST, TEST_F and TEST_P macros per file of tests/*_Test.cpp, taken at version 3.1.4. It is not generated by a script: recount when test files are added or removed.

1. How the library is tested

The gtest binary test_fhsim_marine_elements (tests/CMakeLists.txt) builds the 80 *_Test.cpp files of tests/ plus RunTests.cpp. Shared helpers: tests/TestUtils.h (RunAndCompareRegressionXmlTiming, timing parsing), tests/JacobianTestUtils.h (ExpectJacobiansMatch, a wrapper around fhsim::test::CheckJacobians that fails if nothing was checked) and the *_TestSupport.h headers. tests/CMakeLists.txt also builds the test-only SimObject library fhsim_marine_elements_test_objects (tests/objects/: Test/ForceSource, Test/SignalSink, Test/FlowProbe, Test/NodeTow). It is not installed.

The ctest entries (tests/CMakeLists.txt):

Entry	Runs	Label
`fhsim_marine_elements`	every suite of `test_fhsim_marine_elements` (no `*_SLOW` suite today, so no `_slow` entry)	unit
`fhsim_marine_elements_datasets`	every suite of `test_fhsim_marine_elements_datasets` (`NetValidation_`, `OldVsNew`, `NetPanel`) except `_VALIDATION` and `*_DATAGEN`	regression
`fhsim_marine_elements_datasets_validation`	the `*_VALIDATION` suites of the datasets executable (the Zhan S6 Runge-Kutta case)	validation, slow
`fhsim_marine_elements_datasets_datagen`	the `_DATAGEN` suites (`WritesReport`, which write `tests/out/.txt`)	regression, datagen
`fhsim_marine_elements_perf`	`SimObjectPerf.*`, run with the disabled test	perf
`fhsim_marine_elements_TrawlCable_NoClumpWeight`	one regression test alone in its process	smoke
`fhsim_marine_elements_install_headers`	installs the `library` component into the build tree and compares the header list with `tests/install/installed_headers.txt`	unit

Run the default entry with ctest -R fhsim_marine_elements from the build directory, or call the built test_fhsim_marine_elements[_d] or test_fhsim_marine_elements_datasets[_d] binary with a working directory and a gtest filter (see tests/RunTests.cpp). The conan conf user.fhsim:test_tier decides which entries a conan build runs (see DEVELOPING.md).

Inputs live under tests/in/<SimObjectName>/ (for example tests/in/Disk/Disk_in.xml, Disk_ref.csv, Disk.ref). Auxiliary nets named by File= attributes are copied to the binary's working directory by tests/CMakeLists.txt.

There are 33 regression baselines: tests/in/*/<ID>.ref with <ID>_ref.csv, compared by RunAndCompareRegressionXmlTiming. The baselines, their plots and the owner approvals are in Regression baselines (doc/user/baselines/). The net SimObjects are validated against measurements in Net hydrodynamics: SimObject-level validation report (generated by tests/plot_validation.py).

The only disabled test is SimObjectPerf.DISABLED_NetStructureWithConstraints_RegressionThreads, a wall-clock guard (MARE-0380) that the fhsim_marine_elements_perf entry runs on its own; the fast tier runs the same case against its reference in SimObject.NetStructureWithConstraints_RegressionThreadsMatchesItsReference. See also Disabled tests. No Ogre or visualization-gated tests exist in this suite.

Auto-mode Jacobian checking

fhsim::test::TestSpec.jacobianMode defaults to Auto (fhsim/include/fhsim/testtools/TestSpec.h). A RunTest() call left at that default runs CheckJacobians on the whole scenario after the run, and fails the test on a mismatch, whenever any SimObject in the scenario reports HasJacobians()==true. A test that should not do this sets jacobianMode=No. Tests that call ExpectJacobiansMatch call CheckJacobians directly and bypass jacobianMode. The checker also samples states along the scenario's own integrator (trajectorySamples) and repeats each check with a neutral stateful object placed first (shiftStateOffsets), so every object sits at a non-zero state offset.

2. Test files

File	Tests	Suites
`BodyWake_Test.cpp`	12	`BodyWake`, `Disk`, `BodyWaves`
`CableAxialLaw_Pin_Test.cpp`	4	`CableAxialLawPin`
`CableBranched_FileLookup_Test.cpp`	1	`SimObject`
`CableBranched_FluidRho_Test.cpp`	1	`SimObject`
`CableBranched_Jacobian_Test.cpp`	6	`SimObject`
`CableBranched_PortStorage_Test.cpp`	2	`CableBranched`
`CableBranched_Test.cpp`	4	`SimObject`, `CableBranched`
`CableConnector_Test.cpp`	2	`SimObject`
`CableElBasicsDrag_Test.cpp`	7	`CableElBasicsDrag`, `SimObject`, `CableElBasicsDragJacobian`
`CableElDynStiff_FailedCheck_Test.cpp`	1	`SimObject`
`CableElDynStiff_MeanTension_Test.cpp`	2	`CableElDynStiff`
`CableJointMoment_Test.cpp`	6	`CableJointMoment`
`CableLengthBound_Test.cpp`	2	`CableJacobian`, `CableBranchedJacobian`
`CableMaxTension_Test.cpp`	2	`CableJacobian`, `CableBranchedJacobian`
`CableModelsHydrodynamics_Test.cpp`	6	`CableModelsHydrodynamics`
`CableNumericalDamping_Test.cpp`	4	`CableNumericalDamping`
`CableRMStart_Pin_Test.cpp`	3	`CableRMStartPins`
`CableSegment_Test.cpp`	11	`CableSegment`
`CableWakes_Test.cpp`	17	`CableWakes`
`CableWaves_Test.cpp`	17	`CableWaves`, `ElementWaterLoad`
`Cable_DefaultsMatchDocumentation_Test.cpp`	2	`SimObject`
`Cable_EvaluationOrder_Test.cpp`	5	`CableBranched`, `Cable`
`Cable_Test.cpp`	6	`SimObject`
`Cable_Threads_Test.cpp`	1	`Cable`
`Contracts_Test.cpp`	1	`Contracts`
`Disk_Test.cpp`	8	`SimObject`
`ElementStates_Pin_Test.cpp`	3	`SimObject`
`GaussPointDrag_Test.cpp`	10	`GaussPointDrag`, `SimObject`
`MaxAccelerationRemoved_Test.cpp`	4	`SimObject`
`NetCore_Pin_Test.cpp`	7	`NetCorePin`, `NetCoreCables`
`NetElement3NForces_Test.cpp`	7	`NetElement3NForces`
`NetFlowInteraction_Test.cpp`	5	`NetFlowInteraction`
`NetPanelSetup_Test.cpp`	1	`NetPanelSetup`
`NetSpec_Test.cpp`	45	`TrawlNetSpec`, `TrawlNetSpecReader`, `SNetSection`, `NetStructureSpec`, `NetStructure`, `LoadNet`, `SimObject`, `NetElementDef`
`NetStructureTestFamily_Test.cpp`	6	`NetStructureTestFamily`
`NetStructureWithConstraints_Regression_Test.cpp`	4	`SimObject`, `SimObjectPerf`
`NetStructureWithConstraints_Test.cpp`	17	`SimObject`
`NetStructureWithConstraints_Threads_Test.cpp`	1	`SimObject`
`NetStructureWithConstraints_Wake_Test.cpp`	5	`SimObject`
`NetStructure_BottomContact_Test.cpp`	12	`NetStructureBottomContact`
`NetStructure_CableClamp_Test.cpp`	3	`NetStructureJacobian`
`NetStructure_CableRho_Test.cpp`	6	`SimObject`
`NetStructure_DiskDrag_Test.cpp`	4	`SimObject`
`NetStructure_FileLookup_Test.cpp`	4	`SimObject`, `NetInput`
`NetStructure_FreeDrift_Test.cpp`	1	`SimObject`
`NetStructure_JacobianOptOut_Test.cpp`	8	`SimObject`, `NetStructureBdfTouchdown`
`NetStructure_Jacobian_Test.cpp`	6	`SimObject`, `NetStructurePanelJacobianPerLaw`
`NetStructure_MeanTension_Test.cpp`	1	`NetStructure`
`NetStructure_NanForce_Test.cpp`	1	`SimObject`
`NetStructure_PanelWeight_Test.cpp`	1	`SimObject`
`NetStructure_PortJacobian_Test.cpp`	5	`SimObject`
`NetStructure_PortThreads_Test.cpp`	2	`NetStructure`
`NetStructure_Regression_Test.cpp`	1	`SimObject`
`NetStructure_Solidity_Test.cpp`	12	`SimObject`
`NetStructure_Sparsity_Test.cpp`	3	`NetStructureSparsity`
`NetStructure_Threads_Test.cpp`	3	`SimObject`, `NetThreads`
`NetStructure_Wake_Test.cpp`	11	`SimObject`
`NetStructure_Waves_Test.cpp`	8	`NetStructureWaves`
`NetValidation_LaderCage_Test.cpp`	5	`NetValidation_LaderCage`, `NetValidation_LaderCage_FinalStates`, `NetValidation_LaderCage_DATAGEN`
`NetValidation_TowedPanel_Test.cpp`	6	`NetValidation_TowedPanel`, `NetValidation_TowedPanel_DATAGEN`
`NetValidation_Trawl_Test.cpp`	2	`NetValidation_Trawl`
`NetValidation_ZhanCylinder_Test.cpp`	9	`NetValidation_ZhanCylinder`, `NetValidation_ZhanCylinder_VALIDATION`, `NetValidation_ZhanCylinder_DATAGEN`
`NetWake_Test.cpp`	37	`NetWake`
`OdeJacobian_PortState_Test.cpp`	4	`Cable`, `CableBranched`, `Disk`, `TrawlBeam`
`OldVsNew_Validation_Test.cpp`	15	`OldVsNew`, `OldVsNew_CableRbAngleSweep`, `OldVsNew_CableRbReynoldsSweep`, `OldVsNew_ClumpMeTopTension`, `OldVsNew_NetSheetShape`, `NetPanel`
`OneThreadTwins_Test.cpp`	2	`OneThreadTwin`
`RbCable_Test.cpp`	39	`SimObject`, `CableRM`
`RigidBarCable_Test.cpp`	7	`SimObject`, `RBCEngine`
`SCableSectionData_Test.cpp`	4	`SCableSectionData`
`SeabedContact_Pin_Test.cpp`	9	`SeabedContactPin`
`Sphere_Test.cpp`	6	`SimObject`
`TestUtils_Test.cpp`	16	`TestUtils`
`TrawlBeam_Test.cpp`	4	`SimObject`
`TrawlCableCollisionManager_Test.cpp`	3	`TrawlCableCollisionManager`
`TrawlCableWakes_Test.cpp`	13	`TrawlCableWakes`
`TrawlCableWater_Test.cpp`	4	`TrawlCableWater`
`TrawlMooring_Test.cpp`	28	`SimObject`
`WaveHull_Test.cpp`	25	`WaveHull`
`WavePropulsionHull_Test.cpp`	14	`WavePropulsionHull`
`WetCylinderLaw_Pin_Test.cpp`	5	`WetCylinderLawPin`

Total: 597 tests in 80 files (a TEST_P counts once). The suite name is the first argument of the macro; a suite ending in _VALIDATION runs in the validation entry of the datasets executable, one ending in _DATAGEN in its datagen entry.

3. SimObjects with an analytic Jacobian

HasJacobians() or OdeJacobian is implemented in: Disk, Sphere, Cable (Cable/LumpedMass), CableBranched, CableConnector, NetStructure, TrawlBeam and WaveHull. The others use FhSim's finite-difference fallback. Notes:

Disk, Sphere: dense and hand-derived. Position-velocity identity block, the buoyancy z-gradient inside a smooth region, and the drag block on the velocity relative to the water. The step where the body crosses the surface is left out.
Cable (LumpedMass): the shared kernel InternalCable::ComputeStructuralJacobian (src/cable/subroutines/): position-velocity identity, a numerical-damping diagonal term, and the structural spring and damper blocks of each segment while the tension is inside its bounds.
CableBranched: the same InternalCable blocks plus the junction coupling.
CableConnector: the position-velocity identity block only; its forces are input ports.
NetStructure: cable blocks from the InternalCable kernel; panel blocks by forward-mode automatic differentiation (sfh::ad::Dual<12>) of the templated force core NetElement3NForces (src/net/JACOBIAN_RECIPE.md). HasJacobians() is false, and FhSim uses finite differences, while a mass or velocity adaptation is active, while a cable element carries a sphere or disk, and while a node is in bottom contact (MARE-0134). InputPortJacobian() and OutputPortJacobian() are tested in NetStructure_PortJacobian_Test.cpp with Test/ForceSource and Test/SignalSink. StrainEnergy has no port Jacobian.
TrawlBeam: dense, hand-derived branch by branch to follow the controller's three regimes (power-saturated, force-saturated, unsaturated).