Merge pull request #19249 from Veykril/push-noosrywrsuvn

Fix prefix adjustment hints unnecessarily introducing parens

Author: Veykril

src/tools/rust-analyzer/crates/ide/src/inlay_hints/adjustment.rs

@@ -260,7 +260,7 @@ fn needs_parens_for_adjustment_hints(expr: &ast::Expr, postfix: bool) -> (bool,
 if postfix {
 // postfix ops have higher precedence than any other operator, so we need to wrap
 // any inner expression that is below (except for jumps if they don't have a value)
-let needs_inner_parens = prec < ExprPrecedence::Unambiguous && {
+let needs_inner_parens = prec < ExprPrecedence::Postfix && {
  prec != ExprPrecedence::Jump || !expr.is_ret_like_with_no_value()
 };
 // given we are the higher precedence, no parent expression will have stronger requirements
@@ -276,9 +276,12 @@ fn needs_parens_for_adjustment_hints(expr: &ast::Expr, postfix: bool) -> (bool,
 // if we are already wrapped, great, no need to wrap again
 .filter(|it| !matches!(it, ast::Expr::ParenExpr(_)))
 .map(|it| it.precedence());
+
 // if we have no parent, we don't need outer parens to disambiguate
 // otherwise anything with higher precedence than what we insert needs to wrap us
-let needs_outer_parens = parent.is_some_and(|prec| prec > ExprPrecedence::Prefix);
+// that means only postfix ops
+let needs_outer_parens =
+ parent.is_some_and(|parent_prec| parent_prec == ExprPrecedence::Postfix);
 (needs_outer_parens, needs_inner_parens)
 }
 }
@@ -291,7 +294,7 @@ mod tests {
 };
 
 #[test]
-fnadjustment_hints(){
+fnadjustment_hints_prefix(){
 check_with_config(
 InlayHintsConfig{adjustment_hints:AdjustmentHints::Always, ..DISABLED_CONFIG},
 r#"
@@ -381,6 +384,8 @@ fn main() {
  &mut Struct[0];
  //^^^^^^(&mut $
  //^^^^^^)
+ let _: (&mut (),) = (&mut (),);
+ //^^^^^^^&mut *
 }
 
 #[derive(Copy, Clone)]
@@ -472,6 +477,9 @@ fn main() {
  //^^^^^^.&
  &mut Struct[0];
  //^^^^^^.&mut
+ let _: (&mut (),) = (&mut (),);
+ //^^^^^^^(
+ //^^^^^^^).*.&mut
 }
 
 #[derive(Copy, Clone)]

src/tools/rust-analyzer/crates/syntax/src/ast/prec.rs

@@ -35,7 +35,9 @@ pub enum ExprPrecedence {
 Cast,
 // unary - * ! & &mut
 Prefix,
-// paths, loops, function calls, array indexing, field expressions, method calls
+// function calls, array indexing, field expressions, method calls
+Postfix,
+// paths, loops,
 Unambiguous,
 }
 
@@ -57,6 +59,7 @@ pub fn precedence(expr: &ast::Expr) -> ExprPrecedence {
 },
 
 Expr::BreakExpr(_)
+ | Expr::BecomeExpr(_)
  | Expr::ContinueExpr(_)
  | Expr::ReturnExpr(_)
  | Expr::YeetExpr(_)
@@ -89,27 +92,27 @@ pub fn precedence(expr: &ast::Expr) -> ExprPrecedence {
 
 Expr::LetExpr(_) | Expr::PrefixExpr(_) | Expr::RefExpr(_) => ExprPrecedence::Prefix,
 
+Expr::AwaitExpr(_)
+ | Expr::CallExpr(_)
+ | Expr::FieldExpr(_)
+ | Expr::IndexExpr(_)
+ | Expr::MethodCallExpr(_)
+ | Expr::TryExpr(_) => ExprPrecedence::Postfix,
+
 Expr::ArrayExpr(_)
  | Expr::AsmExpr(_)
- | Expr::AwaitExpr(_)
- | Expr::BecomeExpr(_)
  | Expr::BlockExpr(_)
- | Expr::CallExpr(_)
- | Expr::FieldExpr(_)
  | Expr::ForExpr(_)
  | Expr::FormatArgsExpr(_)
  | Expr::IfExpr(_)
- | Expr::IndexExpr(_)
  | Expr::Literal(_)
  | Expr::LoopExpr(_)
  | Expr::MacroExpr(_)
  | Expr::MatchExpr(_)
- | Expr::MethodCallExpr(_)
  | Expr::OffsetOfExpr(_)
  | Expr::ParenExpr(_)
  | Expr::PathExpr(_)
  | Expr::RecordExpr(_)
- | Expr::TryExpr(_)
  | Expr::TupleExpr(_)
  | Expr::UnderscoreExpr(_)
  | Expr::WhileExpr(_) => ExprPrecedence::Unambiguous,