Mandatory fields for Comprehension (#2099)

2 files changed, 22 insertions, 38 deletions

diff --git a/astroid/nodes/node_classes.py b/astroid/nodes/node_classes.py
index 56921d2d..7b7f532e 100644
--- a/astroid/nodes/node_classes.py
+++ b/astroid/nodes/node_classes.py
@@ -1494,52 +1494,28 @@ class Comprehension(NodeNG):
     optional_assign = True
     """Whether this node optionally assigns a variable."""
 
-    lineno: None
-    col_offset: None
-    end_lineno: None
-    end_col_offset: None
-
-    def __init__(self, parent: NodeNG | None = None) -> None:
-        """
-        :param parent: The parent node in the syntax tree.
-        """
-        self.target: NodeNG | None = None
-        """What is assigned to by the comprehension."""
-
-        self.iter: NodeNG | None = None
-        """What is iterated over by the comprehension."""
+    target: NodeNG
+    """What is assigned to by the comprehension."""
 
-        self.ifs: list[NodeNG] = []
-        """The contents of any if statements that filter the comprehension."""
+    iter: NodeNG
+    """What is iterated over by the comprehension."""
 
-        self.is_async: bool | None = None
-        """Whether this is an asynchronous comprehension or not."""
+    ifs: list[NodeNG]
+    """The contents of any if statements that filter the comprehension."""
 
-        super().__init__(parent=parent)
+    is_async: bool
+    """Whether this is an asynchronous comprehension or not."""
 
-    # pylint: disable=redefined-builtin; same name as builtin ast module.
     def postinit(
         self,
-        target: NodeNG | None = None,
-        iter: NodeNG | None = None,
-        ifs: list[NodeNG] | None = None,
-        is_async: bool | None = None,
+        target: NodeNG,
+        iter: NodeNG,  # pylint: disable = redefined-builtin
+        ifs: list[NodeNG],
+        is_async: bool,
     ) -> None:
-        """Do some setup after initialisation.
-
-        :param target: What is assigned to by the comprehension.
-
-        :param iter: What is iterated over by the comprehension.
-
-        :param ifs: The contents of any if statements that filter
-            the comprehension.
-
-        :param is_async: Whether this is an asynchronous comprehension or not.
-        """
         self.target = target
         self.iter = iter
-        if ifs is not None:
-            self.ifs = ifs
+        self.ifs = ifs
         self.is_async = is_async
 
     assigned_stmts: ClassVar[AssignedStmtsCall[Comprehension]]
diff --git a/astroid/rebuilder.py b/astroid/rebuilder.py
index 5252ac8f..61fbf444 100644
--- a/astroid/rebuilder.py
+++ b/astroid/rebuilder.py
@@ -1009,7 +1009,15 @@ class TreeRebuilder:
         self, node: ast.comprehension, parent: NodeNG
     ) -> nodes.Comprehension:
         """Visit a Comprehension node by returning a fresh instance of it."""
-        newnode = nodes.Comprehension(parent)
+        newnode = nodes.Comprehension(
+            parent=parent,
+            # Comprehension nodes don't have these attributes
+            # see https://docs.python.org/3/library/ast.html#abstract-grammar
+            lineno=None,
+            col_offset=None,
+            end_lineno=None,
+            end_col_offset=None,
+        )
         newnode.postinit(
             self.visit(node.target, newnode),
             self.visit(node.iter, newnode),