fix: support graalpy

Signed-off-by: Henry Schreiner <[email protected]>

Author: henryiii

src/scikit_build_core/builder/_load_provider.py

@@ -125,7 +125,8 @@ def __iter__(self) -> Iterator[str]:
         yield from self.project
 
         # Iterate over the keys of the dynamic metadata providers
-        yield from self.providers
+        # GraalPy needs it to be a copy
+        yield from list(self.providers)
 
     def __len__(self) -> int:
         return len(self.project) + len(self.providers)

tests/test_setuptools_abi3.py

@@ -20,6 +20,9 @@
 @pytest.mark.skipif(
     sys.implementation.name == "pypy", reason="pypy does not support abi3"
 )
+@pytest.mark.skipif(
+    sys.implementation.name == "graalpy", reason="graalpy does not support abi3"
+)
 @pytest.mark.skipif(
     sysconfig.get_config_var("Py_GIL_DISABLED"),
     reason="Free-threaded Python does not support abi3",