Fix formatter with-statement after-as own line comment instability (#6033)

**Summary** Fix an instability in with statement formatter when there is
an own line comment as the `as`
```python
with (
    a as
    # bad comment
    b):
```

**Test Plan** Added the comment to the test cases.

crates/ruff_python_formatter/resources/test/fixtures/ruff/statement/with.py

@@ -25,6 +25,7 @@ with (
 with (
         a  # a
         as  # as
+        # own line
         b  # b
         ,  # comma
         c  # c
@@ -32,6 +33,13 @@ with (
     ...  # body
     # body trailing own
 
+with (
+        a  # a
+        as  # as
+        # own line
+        bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb  # b
+): pass
+
 
 with (a,):  # magic trailing comma
     ...

crates/ruff_python_formatter/src/comments/placement.rs

@@ -1370,15 +1370,15 @@ fn handle_with_item_comment<'a>(
         SimpleTokenKind::As,
     );
 
-    // If before the `as` keyword, then it must be a trailing comment of the context expression.
     if comment.end() < as_token.start() {
+        // If before the `as` keyword, then it must be a trailing comment of the context expression.
         CommentPlacement::trailing(context_expr, comment)
     }
     // Trailing end of line comment coming after the `as` keyword`.
     else if comment.line_position().is_end_of_line() {
         CommentPlacement::dangling(comment.enclosing_node(), comment)
     } else {
-        CommentPlacement::Default(comment)
+        CommentPlacement::leading(optional_vars, comment)
     }
 }
 

crates/ruff_python_formatter/src/other/with_item.rs

@@ -2,7 +2,7 @@ use rustpython_parser::ast::WithItem;
 
 use ruff_formatter::{write, Buffer, FormatResult};
 
-use crate::comments::trailing_comments;
+use crate::comments::{leading_comments, trailing_comments};
 use crate::expression::maybe_parenthesize_expression;
 use crate::expression::parentheses::Parenthesize;
 use crate::prelude::*;
@@ -27,14 +27,22 @@ impl FormatNodeRule<WithItem> for FormatWithItem {
         if let Some(optional_vars) = optional_vars {
             write!(
                 f,
-                [
+                [space(), text("as"), trailing_comments(trailing_as_comments)]
-                    space(),
-                    text("as"),
-                    trailing_comments(trailing_as_comments),
-                    space(),
-                    optional_vars.format(),
-                ]
             )?;
+            let leading_var_comments = comments.leading_comments(optional_vars.as_ref());
+            if leading_var_comments.is_empty() {
+                write!(f, [space(), optional_vars.format()])?;
+            } else {
+                write!(
+                    f,
+                    [
+                        // Otherwise the comment would end up on the same line as the `as`
+                        hard_line_break(),
+                        leading_comments(leading_var_comments),
+                        optional_vars.format()
+                    ]
+                )?;
+            }
         }
         Ok(())
     }

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

@@ -31,6 +31,7 @@ with (
 with (
         a  # a
         as  # as
+        # own line
         b  # b
         ,  # comma
         c  # c
@@ -38,6 +39,13 @@ with (
     ...  # body
     # body trailing own
 
+with (
+        a  # a
+        as  # as
+        # own line
+        bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb  # b
+): pass
+
 
 with (a,):  # magic trailing comma
     ...
@@ -142,12 +150,21 @@ with (
 
 
 with (
-    a as b,  # a  # as  # b  # comma
+    a as  # a  # as
+    # own line
+    b,  # b  # comma
     c,  # c
 ):  # colon
     ...  # body
     # body trailing own
 
+with (
+    a as  # a  # as
+    # own line
+    bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb  # b
+):
+    pass
+
 
 with (
     a,