added nb::hash wrapper

docs/api_core.rst

@@ -2744,6 +2744,12 @@ Miscellaneous
 
    Return the ``globals()`` dictionary.
 
+.. cpp:function:: Py_hash_t hash(handle h)
+
+   Hash the given argument like ``hash()`` in pure Python. The type of the
+   return value (``Py_hash_t``) is an implementation-specific signed integer
+   type.
+
 .. cpp:function:: template <typename Source, typename Target> void implicitly_convertible()
 
    Indicate that the type `Source` is implicitly convertible into `Target`

include/nanobind/nb_misc.h

@@ -46,6 +46,13 @@ inline dict globals() {
     return borrow<dict>(p);
 }
 
+inline Py_hash_t hash(handle h) {
+    Py_hash_t rv = PyObject_Hash(h.ptr());
+    if (rv == -1 && PyErr_Occurred())
+        nanobind::raise_python_error();
+    return rv;
+}
+
 inline bool is_alive() noexcept {
     return detail::is_alive();
 }

tests/test_functions.cpp

@@ -359,4 +359,6 @@ NB_MODULE(test_functions_ext, m) {
 
         return b;
     });
+
+    m.def("hash_it", [](nb::handle h) { return nb::hash(h); });
 }

tests/test_functions.py

@@ -591,3 +591,7 @@ def test43_wrappers_dict():
 
 def test43_wrappers_set():
     assert t.test_wrappers_set()
+
+def test44_hash():
+    value = (1, 2, 3)
+    assert t.hash_it(value) == hash(value);

tests/test_functions_ext.pyi.ref

@@ -5,6 +5,8 @@ from typing import Annotated, Any, overload
 
 def call_guard_value() -> int: ...
 
+def hash_it(arg: object, /) -> int: ...
+
 def identity_i16(arg: int, /) -> int: ...
 
 def identity_i32(arg: int, /) -> int: ...