Fix GraphDef test race condition; correct handle property annotations

- Chain GraphDef kernel launches sequentially (n.launch instead of
  g.launch) to avoid concurrent writes to the same memory location
- Update GraphDef.handle and GraphNode.handle annotations to reflect
  that as_py returns driver types (CUgraph, CUgraphNode), not int

Made-with: Cursor

Author: Andy-Jost

cuda_core/cuda/core/_graph/_graphdef.pyx

@@ -529,8 +529,8 @@ cdef class GraphDef:
         )
 
     @property
-    def handle(self) -> int:
-        """Return the underlying CUgraph handle."""
+    def handle(self):
+        """Return the underlying driver CUgraph handle."""
         return as_py(self._h_graph)
 
 
@@ -624,8 +624,8 @@ cdef class GraphNode:
         return GraphDef._from_handle(graph_node_get_graph(self._h_node))
 
     @property
-    def handle(self) -> int | None:
-        """Return the underlying CUgraphNode handle as an int.
+    def handle(self):
+        """Return the underlying driver CUgraphNode handle.
 
         Returns None for the entry node.
         """

cuda_core/tests/graph/test_graph_update.py

@@ -38,8 +38,8 @@ def build(ptr):
 
         def build(ptr):
             g = GraphDef()
-            g.launch(LaunchConfig(grid=1, block=1), add_one, ptr)
-            g.launch(LaunchConfig(grid=1, block=1), add_one, ptr)
+            n = g.launch(LaunchConfig(grid=1, block=1), add_one, ptr)
+            n.launch(LaunchConfig(grid=1, block=1), add_one, ptr)
             return g.instantiate(), g
 
     graph, _ = build(arr[0:].ctypes.data)