preview-gate both changes

Author: ntBre

crates/ruff_python_formatter/src/context.rs

@@ -112,10 +112,6 @@ impl<'a> PyFormatContext<'a> {
     pub(crate) const fn is_preview(&self) -> bool {
         self.options.preview().is_enabled()
     }
-
-    pub(crate) const fn is_stable(&self) -> bool {
-        !self.is_preview()
-    }
 }
 
 impl FormatContext for PyFormatContext<'_> {

crates/ruff_python_formatter/src/expression/expr_lambda.rs

@@ -8,6 +8,8 @@ use crate::expression::parentheses::{NeedsParentheses, OptionalParentheses, Pare
 use crate::expression::{has_own_parentheses, maybe_parenthesize_expression};
 use crate::other::parameters::ParametersParentheses;
 use crate::prelude::*;
+use crate::preview::is_indent_lambda_parameters_enabled;
+use crate::preview::is_parenthesize_lambda_bodies_enabled;
 
 #[derive(Default)]
 pub struct FormatExprLambda;
@@ -32,44 +34,67 @@ impl FormatNodeRule<ExprLambda> for FormatExprLambda {
             let (dangling_before_parameters, dangling_after_parameters) = dangling
                 .split_at(dangling.partition_point(|comment| comment.end() < parameters.start()));
 
-            if dangling_before_parameters.is_empty() {
-                write!(f, [space()])?;
-            }
+            if is_indent_lambda_parameters_enabled(f.context()) {
+                if dangling_before_parameters.is_empty() {
+                    write!(f, [space()])?;
+                }
 
-            group(&format_with(|f: &mut PyFormatter| {
-                if f.context().node_level().is_parenthesized()
-                    && (parameters.len() > 1 || !dangling_before_parameters.is_empty())
-                {
-                    let end_of_line_start = dangling_before_parameters
-                        .partition_point(|comment| comment.line_position().is_end_of_line());
-                    let (same_line_comments, own_line_comments) =
-                        dangling_before_parameters.split_at(end_of_line_start);
+                group(&format_with(|f: &mut PyFormatter| {
+                    if f.context().node_level().is_parenthesized()
+                        && (parameters.len() > 1 || !dangling_before_parameters.is_empty())
+                    {
+                        let end_of_line_start = dangling_before_parameters
+                            .partition_point(|comment| comment.line_position().is_end_of_line());
+                        let (same_line_comments, own_line_comments) =
+                            dangling_before_parameters.split_at(end_of_line_start);
 
-                    dangling_comments(same_line_comments).fmt(f)?;
+                        dangling_comments(same_line_comments).fmt(f)?;
 
-                    soft_block_indent(&format_args![
-                        leading_comments(own_line_comments),
+                        soft_block_indent(&format_args![
+                            leading_comments(own_line_comments),
+                            parameters
+                                .format()
+                                .with_options(ParametersParentheses::Never),
+                        ])
+                        .fmt(f)
+                    } else {
                         parameters
                             .format()
-                            .with_options(ParametersParentheses::Never),
-                    ])
-                    .fmt(f)
+                            .with_options(ParametersParentheses::Never)
+                            .fmt(f)
+                    }?;
+
+                    token(":").fmt(f)?;
+
+                    if dangling_after_parameters.is_empty() {
+                        space().fmt(f)
+                    } else {
+                        dangling_comments(dangling_after_parameters).fmt(f)
+                    }
+                }))
+                .fmt(f)?;
+            } else {
+                if dangling_before_parameters.is_empty() {
+                    write!(f, [space()])?;
                 } else {
-                    parameters
+                    write!(f, [dangling_comments(dangling_before_parameters)])?;
+                }
+
+                write!(
+                    f,
+                    [parameters
                         .format()
-                        .with_options(ParametersParentheses::Never)
-                        .fmt(f)
-                }?;
+                        .with_options(ParametersParentheses::Never)]
+                )?;
 
-                token(":").fmt(f)?;
+                write!(f, [token(":")])?;
 
                 if dangling_after_parameters.is_empty() {
-                    space().fmt(f)
+                    write!(f, [space()])?;
                 } else {
-                    dangling_comments(dangling_after_parameters).fmt(f)
+                    write!(f, [dangling_comments(dangling_after_parameters)])?;
                 }
-            }))
-            .fmt(f)?;
+            }
         } else {
             write!(f, [token(":")])?;
 
@@ -82,11 +107,13 @@ impl FormatNodeRule<ExprLambda> for FormatExprLambda {
         }
 
         // Avoid parenthesizing lists, dictionaries, etc.
-        if f.context().is_stable() || has_own_parentheses(body, f.context()).is_some() {
-            body.format().fmt(f)
-        } else {
+        if is_parenthesize_lambda_bodies_enabled(f.context())
+            && has_own_parentheses(body, f.context()).is_none()
+        {
             maybe_parenthesize_expression(body, item, Parenthesize::IfBreaksParenthesizedNested)
                 .fmt(f)
+        } else {
+            body.format().fmt(f)
         }
     }
 }

crates/ruff_python_formatter/src/preview.rs

@@ -52,3 +52,16 @@ pub(crate) const fn is_avoid_parens_for_long_as_captures_enabled(
 ) -> bool {
     context.is_preview()
 }
+
+/// Returns `true` if the [`indent_lambda_parameters`](https://github.com/astral-sh/ruff/pull/21385)
+/// preview style is enabled.
+pub(crate) const fn is_indent_lambda_parameters_enabled(context: &PyFormatContext) -> bool {
+    context.is_preview()
+}
+
+/// Returns `true` if the
+/// [`parenthesize_lambda_bodies`](https://github.com/astral-sh/ruff/pull/21385) preview style is
+/// enabled.
+pub(crate) const fn is_parenthesize_lambda_bodies_enabled(context: &PyFormatContext) -> bool {
+    context.is_preview()
+}