Use new IR to format expressions

crates/ruff_python_formatter/src/builders.rs

@@ -21,12 +21,28 @@ pub(crate) struct OptionalParentheses<'a, 'ast> {
 
 impl<'ast> Format<PyFormatContext<'ast>> for OptionalParentheses<'_, 'ast> {
     fn fmt(&self, f: &mut Formatter<PyFormatContext<'ast>>) -> FormatResult<()> {
-        group(&format_args![
+        let saved_level = f.context().node_level();
+
+        let parens_id = f.group_id("optional_parentheses");
+
+        f.context_mut()
+            .set_node_level(NodeLevel::Expression(Some(parens_id)));
+
+        let result = group(&format_args![
             if_group_breaks(&text("(")),
-            soft_block_indent(&Arguments::from(&self.inner)),
+            indent_if_group_breaks(
+                &format_args![soft_line_break(), Arguments::from(&self.inner)],
+                parens_id
+            ),
+            soft_line_break(),
             if_group_breaks(&text(")"))
         ])
-        .fmt(f)
+        .with_group_id(Some(parens_id))
+        .fmt(f);
+
+        f.context_mut().set_node_level(saved_level);
+
+        result
     }
 }
 
@@ -113,7 +129,9 @@ impl<'fmt, 'ast, 'buf> JoinNodesBuilder<'fmt, 'ast, 'buf> {
                         0 | 1 => hard_line_break().fmt(self.fmt),
                         _ => empty_line().fmt(self.fmt),
                     },
-                    NodeLevel::Expression => hard_line_break().fmt(self.fmt),
+                    NodeLevel::Expression(_) | NodeLevel::ParenthesizedExpression => {
+                        hard_line_break().fmt(self.fmt)
+                    }
                 }?;
             }
 
@@ -353,7 +371,7 @@ no_leading_newline = 30"#
     // Removes all empty lines
     #[test]
     fn ranged_builder_parenthesized_level() {
-        let printed = format_ranged(NodeLevel::Expression);
+        let printed = format_ranged(NodeLevel::Expression(None));
 
         assert_eq!(
             &printed,

crates/ruff_python_formatter/src/comments/format.rs

@@ -318,7 +318,9 @@ impl Format<PyFormatContext<'_>> for FormatEmptyLines {
             },
 
             // Remove all whitespace in parenthesized expressions
-            NodeLevel::Expression => write!(f, [hard_line_break()]),
+            NodeLevel::Expression(_) | NodeLevel::ParenthesizedExpression => {
+                write!(f, [hard_line_break()])
+            }
         }
     }
 }

crates/ruff_python_formatter/src/context.rs

@@ -1,6 +1,6 @@
 use crate::comments::Comments;
 use crate::PyFormatOptions;
-use ruff_formatter::{FormatContext, SourceCode};
+use ruff_formatter::{FormatContext, GroupId, SourceCode};
 use ruff_python_ast::source_code::Locator;
 use std::fmt::{Debug, Formatter};
 
@@ -78,6 +78,9 @@ pub(crate) enum NodeLevel {
     /// (`if`, `while`, `match`, etc.).
     CompoundStatement,
 
-    /// Formatting nodes that are enclosed in a parenthesized expression.
-    Expression,
+    /// The root or any sub-expression.
+    Expression(Option<GroupId>),
+
+    /// Formatting nodes that are enclosed by a parenthesized (any `[]`, `{}` or `()`) expression.
+    ParenthesizedExpression,
 }