Handle lambda Arguments dangling comments

crates/ruff_python_formatter/src/expression/expr_lambda.rs

@@ -1,11 +1,12 @@
+use crate::comments::dangling_comments;
 use crate::context::PyFormatContext;
 use crate::expression::parentheses::{NeedsParentheses, OptionalParentheses};
 use crate::other::arguments::ArgumentsParentheses;
 use crate::AsFormat;
 use crate::{FormatNodeRule, PyFormatter};
 use ruff_formatter::prelude::{space, text};
 use ruff_formatter::{write, Buffer, FormatResult};
-use ruff_python_ast::node::AnyNodeRef;
+use ruff_python_ast::node::{AnyNodeRef, AstNode};
 use rustpython_parser::ast::ExprLambda;
 
 #[derive(Default)]
@@ -19,7 +20,11 @@ impl FormatNodeRule<ExprLambda> for FormatExprLambda {
             body,
         } = item;
 
+        let comments = f.context().comments().clone();
+        let dangling = comments.dangling_comments(args.as_any_node_ref());
+
         write!(f, [text("lambda")])?;
+
         if !args.args.is_empty() {
             write!(
                 f,
@@ -30,7 +35,16 @@ impl FormatNodeRule<ExprLambda> for FormatExprLambda {
                 ]
             )?;
         }
-        write!(f, [text(":"), space(), body.format()])
+
+        write!(
+            f,
+            [
+                text(":"),
+                space(),
+                body.format(),
+                dangling_comments(dangling)
+            ]
+        )
     }
 }
 

crates/ruff_python_formatter/src/other/arguments.rs

@@ -191,10 +191,6 @@ impl FormatNodeRule<Arguments> for FormatArguments {
             + usize::from(kwarg.is_some());
 
         if self.parentheses == ArgumentsParentheses::SkipInsideLambda {
-            debug_assert!(
-                dangling.is_empty(),
-                "This node's parentheses cannot be skipped with dangling comments"
-            );
             group(&format_inner).fmt(f)?;
         } else if num_arguments == 0 {
             // No arguments, format any dangling comments between `()`

crates/ruff_python_formatter/tests/snapshots/format@expression__lambda.py.snap

@@ -127,7 +127,9 @@ lambda x: lambda y: lambda z: (
 # Trailing
 
 
-a = lambda: 1  # Dangling
+a = (
+    lambda: 1  # Dangling
+)
 ```