Move to nanobind 3.1 and release 8.0.1.3

The handle caster follows nanobind 3's renamed detail API (keep_alive_cb,
NB_CALL(nb_type_put), uint32_t caster flags). Bound surface unchanged per
sigdiff; list iteration ~4x faster.

pyproject.toml

@@ -1,5 +1,5 @@
 [build-system]
-requires = ["scikit-build-core>=0.11", "nanobind>=2.7,<3"]
+requires = ["scikit-build-core>=0.11", "nanobind>=3.1,<4"]
 build-backend = "scikit_build_core.build"
 
 [project]
@@ -9,7 +9,7 @@ name = "n3xd-ocp"
 # .devN suffix: the registry never allows republishing a version, and its
 # cleanup rule collects only the dev ones.  CMake asserts the prefix matches
 # the OCCT it found.
-version = "8.0.1.2"
+version = "8.0.1.3"
 description = "nanobind bindings for the OpenCASCADE geometry kernel (drop-in OCP)"
 readme = "README.md"
 requires-python = ">=3.12"

scripts/_env.sh

@@ -24,10 +24,10 @@ if [ ! -x "$VENV/bin/python" ]; then
     "$VENV/bin/pip" install -q --upgrade pip
     # numpy is a test dependency only: the n3xd_ocp bulk APIs hand back
     # ndarrays, so their tests need it to check the results.
-    # nanobind 3 reworked the type-caster and rv_policy interfaces
-    # occt_handle.h builds on, so moving to it is a deliberate bump, not
-    # something a fresh cache picks up.
-    "$VENV/bin/pip" install -q build "nanobind<3" scikit-build-core pytest numpy
+    # occt_handle.h builds on nanobind's detail API, which moves between
+    # majors, so the next one is a deliberate bump, not something a fresh
+    # cache picks up.
+    "$VENV/bin/pip" install -q build "nanobind>=3.1,<4" scikit-build-core pytest numpy
 fi
 PY="$VENV/bin/python"
 export PY VENV CACHE

src/common/occt_handle.h

@@ -44,7 +44,7 @@ NAMESPACE_BEGIN(detail)
 inline NB_NOINLINE void
 occt_handle_keep_alive(opencascade::handle<Standard_Transient> &&h,
                        PyObject *o) noexcept {
-    keep_alive(o, new opencascade::handle<Standard_Transient>(std::move(h)),
+    keep_alive_cb(o, new opencascade::handle<Standard_Transient>(std::move(h)),
                   [](void *p) noexcept {
                       delete (opencascade::handle<Standard_Transient> *) p;
                   });
@@ -64,7 +64,7 @@ struct type_caster<
                   "Conversion of opencascade::handle<T> requires that T is "
                   "bound through nanobind's regular class mechanism.");
 
-    bool from_python(handle src, uint8_t flags,
+    bool from_python(handle src, uint32_t flags,
                      cleanup_list *cleanup) noexcept {
         // A null handle is OCCT's absent value and maps to None in both
         // directions; several APIs (BRep_Tool::Surface on a degenerate edge,
@@ -74,7 +74,7 @@ struct type_caster<
             return true;
         }
 
-        flags &= ~((uint8_t) cast_flags::convert);
+        flags &= ~cast_flags::convert;
 
         Caster caster;
         if (!caster.from_python(src, flags, cleanup))
@@ -106,7 +106,8 @@ struct type_caster<
         // dynamic type: BRep_Tool::Surface returning a Geom_Surface handle to
         // a plane arrives in Python as Geom_Plane when that class is bound.
         bool is_new = false;
-        handle result = nb_type_put_p(&typeid(Td), &typeid(*ptr), (void *) ptr,
+        handle result = NB_CALL(nb_type_put)(
+            NB_CTX_C(cleanup), &typeid(Td), &typeid(*ptr), (void *) ptr,
             rv_policy::reference, cleanup, &is_new);
 
         // Only a freshly created wrapper takes a reference.  Attaching one per