chore: import upstream snapshot with attribution

python/ray/dag/function_node.py

@@ -0,0 +1,59 @@
+from typing import Any, Dict, List
+
+import ray
+from ray.dag.dag_node import DAGNode
+from ray.dag.format_utils import get_dag_node_str
+from ray.util.annotations import DeveloperAPI
+
+
+@DeveloperAPI
+class FunctionNode(DAGNode):
+    """Represents a bound task node in a Ray task DAG."""
+
+    def __init__(
+        self,
+        func_body,
+        func_args,
+        func_kwargs,
+        func_options,
+        other_args_to_resolve=None,
+    ):
+        self._body = func_body
+        super().__init__(
+            func_args,
+            func_kwargs,
+            func_options,
+            other_args_to_resolve=other_args_to_resolve,
+        )
+
+    def _copy_impl(
+        self,
+        new_args: List[Any],
+        new_kwargs: Dict[str, Any],
+        new_options: Dict[str, Any],
+        new_other_args_to_resolve: Dict[str, Any],
+    ):
+        return FunctionNode(
+            self._body,
+            new_args,
+            new_kwargs,
+            new_options,
+            other_args_to_resolve=new_other_args_to_resolve,
+        )
+
+    def _execute_impl(self, *args, **kwargs):
+        """Executor of FunctionNode by ray.remote().
+
+        Args and kwargs are to match base class signature, but not in the
+        implementation. All args and kwargs should be resolved and replaced
+        with value in bound_args and bound_kwargs via bottom-up recursion when
+        current node is executed.
+        """
+        return (
+            ray.remote(self._body)
+            .options(**self._bound_options)
+            .remote(*self._bound_args, **self._bound_kwargs)
+        )
+
+    def __str__(self) -> str:
+        return get_dag_node_str(self, str(self._body))