Add ParamSpec node

Author: jacobtylerwalls

astroid/nodes/__init__.py

@@ -71,6 +71,7 @@
     NamedExpr,
     NodeNG,
     Nonlocal,
+    ParamSpec,
     Pass,
     Pattern,
     Raise,
@@ -182,6 +183,7 @@
     NamedExpr,
     NodeNG,
     Nonlocal,
+    ParamSpec,
     Pass,
     Pattern,
     Raise,
@@ -275,6 +277,7 @@
     "NamedExpr",
     "NodeNG",
     "Nonlocal",
+    "ParamSpec",
     "Pass",
     "Position",
     "Raise",

astroid/nodes/as_string.py

@@ -433,6 +433,10 @@ def visit_nonlocal(self, node) -> str:
         """return an astroid.Nonlocal node as string"""
         return f"nonlocal {', '.join(node.names)}"
 
+    def visit_paramspec(self, node: nodes.ParamSpec) -> str:
+        """return an astroid.ParamSpec node as string"""
+        return node.name
+
     def visit_pass(self, node) -> str:
         """return an astroid.Pass node as string"""
         return "pass"

astroid/nodes/node_classes.py

@@ -2695,6 +2695,52 @@ def _infer_name(self, frame, name):
         return name
 
 
+class ParamSpec(_base_nodes.AssignTypeNode):
+    """Class representing a :class:`ast.ParamSpec` node.
+
+    >>> import astroid
+    >>> node = astroid.extract_node('type Alias[**P] = Callable[P, int]')
+    >>> node.type_params[0]
+    <ParamSpec l.1 at 0x7f23b2e4e198>
+    """
+
+    def __init__(
+        self,
+        lineno: int | None = None,
+        col_offset: int | None = None,
+        parent: NodeNG | None = None,
+        *,
+        end_lineno: int | None = None,
+        end_col_offset: int | None = None,
+    ) -> None:
+        self.name: str
+        super().__init__(
+            lineno=lineno,
+            col_offset=col_offset,
+            end_lineno=end_lineno,
+            end_col_offset=end_col_offset,
+            parent=parent,
+        )
+
+    def postinit(self, name: str) -> None:
+        self.name = name
+
+    assigned_stmts: ClassVar[
+        Callable[
+            [
+                ParamSpec,
+                AssignName,
+                InferenceContext | None,
+                None,
+            ],
+            Generator[NodeNG, None, None],
+        ]
+    ]
+    """Returns the assigned statement (non inferred) according to the assignment type.
+    See astroid/protocols.py for actual implementation.
+    """
+
+
 class Pass(_base_nodes.NoChildrenNode, _base_nodes.Statement):
     """Class representing an :class:`ast.Pass` node.
 
@@ -3329,7 +3375,7 @@ def __init__(
         end_lineno: int | None = None,
         end_col_offset: int | None = None,
     ) -> None:
-        self.type_params: list[TypeVar]
+        self.type_params: list[TypeVar, ParamSpec]
         self.value: NodeNG
         super().__init__(
             lineno=lineno,
@@ -3342,7 +3388,7 @@ def __init__(
     def postinit(
         self,
         *,
-        type_params: list[TypeVar],
+        type_params: list[TypeVar, ParamSpec],
         value: NodeNG,
     ) -> None:
         self.type_params = type_params

astroid/rebuilder.py

@@ -384,6 +384,12 @@ def visit(self, node: ast.Nonlocal, parent: NodeNG) -> nodes.Nonlocal:
         def visit(self, node: ast.Constant, parent: NodeNG) -> nodes.Const:
             ...
 
+        if sys.version_info >= (3, 12):
+
+            @overload
+            def visit(self, node: ast.ParamSpec, parent: NodeNG) -> nodes.ParamSpec:
+                ...
+
         @overload
         def visit(self, node: ast.Pass, parent: NodeNG) -> nodes.Pass:
             ...
@@ -1493,6 +1499,18 @@ def visit_constant(self, node: ast.Constant, parent: NodeNG) -> nodes.Const:
             parent=parent,
         )
 
+    def visit_paramspec(self, node: ast.ParamSpec, parent: NodeNG) -> nodes.ParamSpec:
+        """Visit a ParamSpec node by returning a fresh instance of it."""
+        newnode = nodes.ParamSpec(
+            lineno=node.lineno,
+            col_offset=node.col_offset,
+            end_lineno=node.end_lineno,
+            end_col_offset=node.end_col_offset,
+            parent=parent,
+        )
+        newnode.postinit(node.name)
+        return newnode
+
     def visit_pass(self, node: ast.Pass, parent: NodeNG) -> nodes.Pass:
         """Visit a Pass node by returning a fresh instance of it."""
         return nodes.Pass(

doc/api/astroid.nodes.rst

@@ -67,6 +67,7 @@ Nodes
    astroid.nodes.Module
    astroid.nodes.Name
    astroid.nodes.Nonlocal
+   astroid.nodes.ParamSpec
    astroid.nodes.Pass
    astroid.nodes.Raise
    astroid.nodes.Return
@@ -204,6 +205,8 @@ Nodes
 
 .. autoclass:: astroid.nodes.Nonlocal
 
+.. autoclass:: astroid.nodes.ParamSpec
+
 .. autoclass:: astroid.nodes.Pass
 
 .. autoclass:: astroid.nodes.Raise

tests/test_type_params.py

@@ -6,7 +6,7 @@
 
 from astroid import extract_node
 from astroid.const import PY312_PLUS
-from astroid.nodes import Subscript, TypeAlias, TypeVar
+from astroid.nodes import ParamSpec, Subscript, TypeAlias, TypeVar
 
 
 @pytest.mark.skipif(not PY312_PLUS, reason="Requires Python 3.12 or higher")
@@ -23,6 +23,14 @@ def test_type_alias() -> None:
     assert all(elt.name == "float" for elt in node.value.slice.elts)
 
 
+@pytest.mark.skipif(not PY312_PLUS, reason="Requires Python 3.12 or higher")
+def test_type_param_spec() -> None:
+    node = extract_node("type Alias[**P] = Callable[P, int]")
+    params = node.type_params[0]
+    assert isinstance(params, ParamSpec)
+    assert params.name == "P"
+    
+
 @pytest.mark.skipif(not PY312_PLUS, reason="Requires Python 3.12 or higher")
 def test_type_param() -> None:
     func_node = extract_node("def func[T]() -> T: ...")