Skip GC-dependent tests on GraalPy (#5401)

Author: msimacek

tests/test_class_sh_property.py

@@ -11,7 +11,9 @@
     pytest.skip("smart_holder not available.", allow_module_level=True)
 
 
-@pytest.mark.xfail("env.PYPY", reason="gc after `del field` is apparently deferred")
+@pytest.mark.skipif(
+    "env.PYPY or env.GRAALPY", reason="gc after `del field` is apparently deferred"
+)
 @pytest.mark.parametrize("m_attr", ["m_valu_readonly", "m_valu_readwrite"])
 def test_valu_getter(m_attr):
     # Reduced from PyCLIF test:

tests/test_class_sh_trampoline_shared_from_this.py

@@ -212,10 +212,10 @@ def test_multiple_registered_instances_for_same_pointee_recursive():
             del obj_next
             assert obj.history == "PySft"
         del obj0
-        if not env.PYPY:
+        if not env.PYPY and not env.GRAALPY:
             assert obj0_wr() is not None
         del obj  # This releases the chain recursively.
-        if not env.PYPY:
+        if not env.PYPY and not env.GRAALPY:
             assert obj0_wr() is None
         break  # Comment out for manual leak checking (use `top` command).
 

tests/test_class_sh_trampoline_shared_ptr_cpp_arg.py

@@ -2,12 +2,14 @@
 
 import pytest
 
+import env  # noqa: F401
 import pybind11_tests.class_sh_trampoline_shared_ptr_cpp_arg as m
 
 if not m.defined_PYBIND11_SMART_HOLDER_ENABLED:
     pytest.skip("smart_holder not available.", allow_module_level=True)
 
 
+@pytest.mark.skipif("env.GRAALPY", reason="Cannot reliably trigger GC")
 def test_shared_ptr_cpp_arg():
     import weakref
 
@@ -32,6 +34,7 @@ def is_base_used(self):
     assert tester.get_object() is objref()
 
 
+@pytest.mark.skipif("env.GRAALPY", reason="Cannot reliably trigger GC")
 def test_shared_ptr_cpp_prop():
     class PyChild(m.SpBase):
         def is_base_used(self):
@@ -50,6 +53,7 @@ def is_base_used(self):
     assert tester.obj.has_python_instance() is True
 
 
+@pytest.mark.skipif("env.GRAALPY", reason="Cannot reliably trigger GC")
 def test_shared_ptr_arg_identity():
     import weakref
 
@@ -68,6 +72,7 @@ def test_shared_ptr_arg_identity():
     assert tester.has_python_instance() is False
 
 
+@pytest.mark.skipif("env.GRAALPY", reason="Cannot reliably trigger GC")
 def test_shared_ptr_alias_nonpython():
     tester = m.SpBaseTester()
 
@@ -110,6 +115,7 @@ def test_shared_ptr_alias_nonpython():
     assert new_tester.has_python_instance() is False
 
 
+@pytest.mark.skipif("env.GRAALPY", reason="Cannot reliably trigger GC")
 def test_shared_ptr_goaway():
     import weakref