Improve typing of inference functions (#2166)

Co-authored-by: Daniël van Noord <13665637+DanielNoord@users.noreply.github.com>

1 files changed, 18 insertions, 3 deletions

diff --git a/astroid/nodes/node_ng.py b/astroid/nodes/node_ng.py
index de5dec77..31c842ee 100644
--- a/astroid/nodes/node_ng.py
+++ b/astroid/nodes/node_ng.py
@@ -5,6 +5,7 @@
 from __future__ import annotations
 
 import pprint
+import sys
 import warnings
 from collections.abc import Generator, Iterator
 from functools import cached_property
@@ -37,6 +38,12 @@ from astroid.nodes.const import OP_PRECEDENCE
 from astroid.nodes.utils import Position
 from astroid.typing import InferenceErrorInfo, InferenceResult, InferFn
 
+if sys.version_info >= (3, 11):
+    from typing import Self
+else:
+    from typing_extensions import Self
+
+
 if TYPE_CHECKING:
     from astroid import nodes
 
@@ -80,7 +87,7 @@ class NodeNG:
     _other_other_fields: ClassVar[tuple[str, ...]] = ()
     """Attributes that contain AST-dependent fields."""
     # instance specific inference function infer(node, context)
-    _explicit_inference: InferFn | None = None
+    _explicit_inference: InferFn[Self] | None = None
 
     def __init__(
         self,
@@ -137,9 +144,17 @@ class NodeNG:
             # explicit_inference is not bound, give it self explicitly
             try:
                 if context is None:
-                    yield from self._explicit_inference(self, context, **kwargs)
+                    yield from self._explicit_inference(
+                        self,  # type: ignore[arg-type]
+                        context,
+                        **kwargs,
+                    )
                     return
-                for result in self._explicit_inference(self, context, **kwargs):
+                for result in self._explicit_inference(
+                    self,  # type: ignore[arg-type]
+                    context,
+                    **kwargs,
+                ):
                     context.nodes_inferred += 1
                     yield result
                 return