[tests/python] test_finite_diff.py does not require Pinocchio, just use pytest.mark.skipif if not present

[python] Add helper function has_pinocchio_features()

Author: ManifoldFR

bindings/python/src/module.cpp

@@ -81,6 +81,19 @@ BOOST_PYTHON_MODULE(MODULE_NAME) {
   bp::import("warnings");
   bp::import("proxsuite_nlp");
 
+  bp::def(
+      "has_pinocchio_features",
+      +[]() constexpr -> bool {
+        return
+#ifdef ALIGATOR_WITH_PINOCCHIO
+            true;
+#else
+            false;
+#endif
+      },
+      "Whether Aligator (and its Python bindings) were compiled with support "
+      "for Pinocchio.");
+
   exposeContainers();
   exposeGAR();
   exposeEnums();

tests/python/CMakeLists.txt

@@ -16,7 +16,6 @@ if(NOT BUILD_WITH_PINOCCHIO_PYTHON_BINDINGS)
 endif()
 if(NOT PINOCCHIO_V3)
   list(REMOVE_ITEM PYTHON_TESTS test_constrained_dynamics.py)
-  list(REMOVE_ITEM PYTHON_TESTS test_finite_diff.py)
   list(REMOVE_ITEM PYTHON_TESTS test_frames.py)
 endif()
 make_directory(${CMAKE_CURRENT_BINARY_DIR})

tests/python/test_finite_diff.py

@@ -5,8 +5,19 @@
     ControlBoxFunction,
     StateErrorResidual,
     manifolds,
+    has_pinocchio_features,
 )
 import numpy as np
+import pytest
+
+# Attempt importing Pinocchio at least. Then, check if the Python module
+# has Pinocchio features.
+try:
+    import pinocchio as pin
+
+    HAS_PINOCCHIO = has_pinocchio_features()
+except ImportError:
+    HAS_PINOCCHIO = False
 
 
 def test_compute_jac_vs():
@@ -31,32 +42,28 @@ def test_compute_jac_vs():
         assert np.allclose(fdata1.Jy, fdata1b.Jy, 1e-2)
 
 
+@pytest.mark.skipif(not HAS_PINOCCHIO, reason="Pinocchio bindings not present.")
 def test_compute_jac_multibody():
-    try:
-        import pinocchio as pin
-
-        model = pin.buildSampleModelHumanoid()
-        space = manifolds.MultibodyConfiguration(model)
-        nu = 3
-        x_tar = space.neutral()
-        fun2 = StateErrorResidual(space, nu, x_tar)
-        fdata2 = fun2.createData()
-        fun2_fd = FiniteDifferenceHelper(space, fun2, 1e-6)
-        fdata2b = fun2_fd.createData()
-        for i in range(1000):
-            x0 = pin.randomConfiguration(model, -np.ones(model.nq), np.ones(model.nq))
-            u0 = 0.6 * np.ones(nu)
-            fun2.evaluate(x0, u0, x0, fdata2)
-            fun2_fd.evaluate(x0, u0, x0, fdata2b)
-            assert np.allclose(fdata2.value, fdata2b.value, 1e-2)
-            fun2.computeJacobians(x0, u0, x0, fdata2)
-            fun2_fd.computeJacobians(x0, u0, x0, fdata2b)
-            assert np.allclose(fdata2.Jx, fdata2b.Jx, 1e-2)
-            assert np.allclose(fdata2.Ju, fdata2b.Ju, 1e-2)
-            assert np.allclose(fdata2.Jy, fdata2b.Jy, 1e-2)
-        return
-    except ImportError:
-        pass
+    model = pin.buildSampleModelHumanoid()
+    space = manifolds.MultibodyConfiguration(model)
+    nu = 3
+    x_tar = space.neutral()
+    fun2 = StateErrorResidual(space, nu, x_tar)
+    fdata2 = fun2.createData()
+    fun2_fd = FiniteDifferenceHelper(space, fun2, 1e-6)
+    fdata2b = fun2_fd.createData()
+    for i in range(1000):
+        x0 = pin.randomConfiguration(model, -np.ones(model.nq), np.ones(model.nq))
+        u0 = 0.6 * np.ones(nu)
+        fun2.evaluate(x0, u0, x0, fdata2)
+        fun2_fd.evaluate(x0, u0, x0, fdata2b)
+        assert np.allclose(fdata2.value, fdata2b.value, 1e-2)
+        fun2.computeJacobians(x0, u0, x0, fdata2)
+        fun2_fd.computeJacobians(x0, u0, x0, fdata2b)
+        assert np.allclose(fdata2.Jx, fdata2b.Jx, 1e-2)
+        assert np.allclose(fdata2.Ju, fdata2b.Ju, 1e-2)
+        assert np.allclose(fdata2.Jy, fdata2b.Jy, 1e-2)
+    return
 
 
 def test_compute_cost_se3():