apply Micha's patch, fixing everything?

Co-authored-by: Micha Reiser <micha@reiser.io>

crates/ruff_python_formatter/src/expression/expr_lambda.rs

@@ -1,14 +1,11 @@
-use ruff_formatter::{FormatRuleWithOptions, RemoveSoftLinesBuffer, write};
+use ruff_formatter::{FormatRuleWithOptions, RemoveSoftLinesBuffer, format_args, write};
 use ruff_python_ast::{AnyNodeRef, Expr, ExprLambda};
 use ruff_text_size::Ranged;
 
 use crate::builders::parenthesize_if_expands;
 use crate::comments::dangling_comments;
 use crate::expression::has_own_parentheses;
-use crate::expression::maybe_parenthesize_expression;
-use crate::expression::parentheses::{
-    NeedsParentheses, OptionalParentheses, Parenthesize, is_expression_parenthesized,
-};
+use crate::expression::parentheses::{NeedsParentheses, OptionalParentheses, Parentheses};
 use crate::other::parameters::ParametersParentheses;
 use crate::prelude::*;
 use crate::preview::is_force_single_line_lambda_parameters_enabled;
@@ -83,28 +80,32 @@ impl FormatNodeRule<ExprLambda> for FormatExprLambda {
             }
         }
 
-        // Avoid parenthesizing lists, dictionaries, etc. that have their own parentheses, but still
-        // wrap calls and subscripts, which can have long expressions before the parentheses:
-        // ```py
-        // lambda arg1, arg2, arg3, *args, **kwargs: a_loooooooooooong_call_expression.with_an_attr(inner, args)
-        // ```
-        let needs_parentheses = has_own_parentheses(body, f.context()).is_none()
-            || matches!(&**body, Expr::Call(_) | Expr::Subscript(_));
+        if is_parenthesize_lambda_bodies_enabled(f.context()) {
+            let fmt_body = format_with(|f| {
+                if matches!(&**body, Expr::Call(_) | Expr::Subscript(_)) {
+                    let body = body.format().with_options(Parentheses::Never).memoized();
 
-        if is_parenthesize_lambda_bodies_enabled(f.context())
-            && needs_parentheses
-            && !is_expression_parenthesized(body.into(), comments.ranges(), f.context().source())
-        {
-            match self.layout {
-                ExprLambdaLayout::Default => maybe_parenthesize_expression(
-                    body,
-                    item,
-                    Parenthesize::IfBreaksParenthesizedNested,
-                )
-                .fmt(f),
-                ExprLambdaLayout::Assignment => {
-                    fits_expanded(&parenthesize_if_expands(&body.format())).fmt(f)
+                    best_fitting![
+                        // body all flat
+                        body,
+                        // body expanded
+                        body,
+                        // parenthesized
+                        format_args![token("("), block_indent(&body), token(")")]
+                    ]
+                    .fmt(f)
+                } else if has_own_parentheses(body, f.context()).is_some() {
+                    // We probably need to be more careful here and preserve parentheses if there are comments?
+                    body.format().fmt(f)
+                } else {
+                    parenthesize_if_expands(&body.format().with_options(Parentheses::Never)).fmt(f)
                 }
+            });
+
+            match self.layout {
+                // Can we move the `fits_expanded` into the assignment formatting?
+                ExprLambdaLayout::Assignment => fits_expanded(&fmt_body).fmt(f),
+                ExprLambdaLayout::Default => fmt_body.fmt(f),
             }
         } else {
             body.format().fmt(f)

crates/ruff_python_formatter/tests/snapshots/black_compatibility@cases__preview_multiline_strings.py.snap

@@ -375,7 +375,7 @@ a = b if """
  # Another use case
  data = yaml.load("""\
  a: 1
-@@ -77,19 +106,23 @@
+@@ -77,10 +106,12 @@
  b: 2
  """,
  )
@@ -390,19 +390,7 @@ a = b if """
  
  MULTILINE = """
  foo
- """.replace("\n", "")
--generated_readme = lambda project_name: """
-+generated_readme = lambda project_name: (
-+    """
- {}
- 
- <Add content here!>
- """.strip().format(project_name)
-+)
- parser.usage += """
- Custom extra help summary.
- 
-@@ -156,16 +189,24 @@
+@@ -156,16 +187,24 @@
               10 LOAD_CONST               0 (None)
               12 RETURN_VALUE
  """ % (_C.__init__.__code__.co_firstlineno + 1,)
@@ -433,7 +421,7 @@ a = b if """
  [
      """cow
  moos""",
-@@ -206,7 +247,9 @@
+@@ -206,7 +245,9 @@
      "c"
  )
  
@@ -444,7 +432,7 @@ a = b if """
  
  assert some_var == expected_result, """
  test
-@@ -224,10 +267,8 @@
+@@ -224,10 +265,8 @@
                  """Sxxxxxxx xxxxxxxx, xxxxxxx xx xxxxxxxxx
                  xxxxxxxxxxxxx xxxxxxx xxxxxxxxx xxx-xxxxxxxxxx xxxxxx xx xxx-xxxxxx"""
              ),
@@ -457,7 +445,7 @@ a = b if """
          },
      }
  
-@@ -246,14 +287,12 @@
+@@ -246,14 +285,12 @@
  a
  a"""
      ),
@@ -597,13 +585,11 @@ data = yaml.load(
 MULTILINE = """
 foo
 """.replace("\n", "")
-generated_readme = lambda project_name: (
-    """
+generated_readme = lambda project_name: """
 {}
 
 <Add content here!>
 """.strip().format(project_name)
-)
 parser.usage += """
 Custom extra help summary.
 

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

@@ -913,7 +913,27 @@ if 1:
  ):
      pass
  
-@@ -218,71 +200,79 @@
+@@ -156,7 +138,8 @@
+     *x: x
+ )
+ 
+-lambda: (  # comment
++lambda: (
++    # comment
+     x
+ )
+ 
+@@ -184,7 +167,8 @@
+ 
+ (
+     lambda:  # comment
+-    (  # comment
++    (
++        # comment
+         x
+     )
+ )
+@@ -218,71 +202,79 @@
  
  # Leading
  lambda x: (
@@ -1052,7 +1072,7 @@ if 1:
  
  
  # Regression tests for https://github.com/astral-sh/ruff/issues/8179
-@@ -291,9 +281,9 @@
+@@ -291,9 +283,9 @@
          c,
          d,
          e,
@@ -1065,7 +1085,7 @@ if 1:
      )
  
  
-@@ -302,15 +292,9 @@
+@@ -302,15 +294,9 @@
          c,
          d,
          e,
@@ -1084,7 +1104,7 @@ if 1:
          g=10,
      )
  
-@@ -320,9 +304,9 @@
+@@ -320,9 +306,9 @@
          c,
          d,
          e,
@@ -1097,7 +1117,7 @@ if 1:
      )
  
  
-@@ -338,9 +322,9 @@
+@@ -338,9 +324,9 @@
  
  class C:
      function_dict: Dict[Text, Callable[[CRFToken], Any]] = {
@@ -1110,7 +1130,7 @@ if 1:
      }
  
  
-@@ -352,42 +336,40 @@
+@@ -352,42 +338,40 @@
  def foo():
      if True:
          if True:
@@ -1169,7 +1189,7 @@ if 1:
          CREATE TABLE {table} AS
          SELECT ROW_NUMBER() OVER () AS id, {var}
          FROM (
-@@ -408,12 +390,12 @@
+@@ -408,12 +392,12 @@
      # 6
  )
  
@@ -1186,7 +1206,7 @@ if 1:
  )
  
  very_long_variable_name_x, very_long_variable_name_y = (
-@@ -421,8 +403,8 @@
+@@ -421,8 +405,8 @@
      lambda b: b * another_very_long_expression_here,
  )
  
@@ -1197,19 +1217,4 @@ if 1:
          x, more_args, additional_parameters
      )
  )
-@@ -433,9 +415,11 @@
-         if 3:
-             if self.location in EVM_EVMLIKE_LOCATIONS and database is not None:
-                 exported_dict["notes"] = EVM_ADDRESS_REGEX.sub(
--                    repl=lambda matched_address: self._maybe_add_label_with_address(
--                        database=database,
--                        matched_address=matched_address,
-+                    repl=lambda matched_address: (
-+                        self._maybe_add_label_with_address(
-+                            database=database,
-+                            matched_address=matched_address,
-+                        )
-                     ),
-                     string=exported_dict["notes"],
-                 )
 ```

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

@@ -111,15 +111,16 @@ generated_readme = (
 ```diff
 --- Stable
 +++ Preview
-@@ -44,8 +44,8 @@
+@@ -44,10 +44,8 @@
  # this by changing `Lambda::needs_parentheses` to return `BestFit` but it causes
  # issues when the lambda has comments.
  # Let's keep this as a known deviation for now.
 -generated_readme = (
 -    lambda project_name: """
-+generated_readme = lambda project_name: (
-+    """
++generated_readme = lambda project_name: """
  {}
  
  <Add content here!>
+ """.strip().format(project_name)
+-)
 ```