rust-analyzer

diff --git a/crates/ide/src/inlay_hints.rs b/crates/ide/src/inlay_hints.rs
index d7d3171664..cc44ae8fc8 100644
--- a/crates/ide/src/inlay_hints.rs
+++ b/crates/ide/src/inlay_hints.rs

@@ -306,6 +306,7 @@ pub struct InlayHintsConfig {

pub generic_parameter_hints: GenericParameterHints,

pub chaining_hints: bool,

pub adjustment_hints: AdjustmentHints,

+ pub adjustment_hints_disable_reborrows: bool,

pub adjustment_hints_mode: AdjustmentHintsMode,

pub adjustment_hints_hide_outside_unsafe: bool,

pub closure_return_type_hints: ClosureReturnTypeHints,

@@ -430,7 +431,7 @@ pub enum LifetimeElisionHints {

#[derive(Clone, Debug, PartialEq, Eq)]

pub enum AdjustmentHints {

Always,

- ReborrowOnly,

+ BorrowsOnly,

Never,

}

@@ -886,6 +887,7 @@ mod tests {

closure_return_type_hints: ClosureReturnTypeHints::Never,

closure_capture_hints: false,

adjustment_hints: AdjustmentHints::Never,

+ adjustment_hints_disable_reborrows: false,

adjustment_hints_mode: AdjustmentHintsMode::Prefix,

adjustment_hints_hide_outside_unsafe: false,

binding_mode_hints: false,

diff --git a/crates/ide/src/inlay_hints/adjustment.rs b/crates/ide/src/inlay_hints/adjustment.rs
index e39a5f8889..0fd587a728 100644
--- a/crates/ide/src/inlay_hints/adjustment.rs
+++ b/crates/ide/src/inlay_hints/adjustment.rs

@@ -47,7 +47,22 @@ pub(super) fn hints(

let descended = sema.descend_node_into_attributes(expr.clone()).pop();

let desc_expr = descended.as_ref().unwrap_or(expr);

- let adjustments = sema.expr_adjustments(desc_expr).filter(|it| !it.is_empty())?;

+ let mut adjustments = sema.expr_adjustments(desc_expr).filter(|it| !it.is_empty())?;

+ if config.adjustment_hints_disable_reborrows {

+ // Remove consecutive deref-ref, i.e. reborrows.

+ let mut i = 0;

+ while i < adjustments.len().saturating_sub(1) {

+ let [current, next, ..] = &adjustments[i..] else { unreachable!() };

+ if matches!(current.kind, Adjust::Deref(None))

+ && matches!(next.kind, Adjust::Borrow(AutoBorrow::Ref(_)))

+ {

+ adjustments.splice(i..i + 2, []);

+ } else {

+ i += 1;

+ }

if let ast::Expr::BlockExpr(_) | ast::Expr::IfExpr(_) | ast::Expr::MatchExpr(_) = desc_expr {

// Don't show unnecessary reborrows for these, they will just repeat the inner ones again

@@ -719,4 +734,36 @@ fn hello(it: &&[impl T]) {

"#,

);

}

+ #[test]

+ fn disable_reborrows() {

+ check_with_config(

+ InlayHintsConfig {

+ adjustment_hints: AdjustmentHints::Always,

+ adjustment_hints_disable_reborrows: true,

+ ..DISABLED_CONFIG

+ },

+ r#"

+#![rustc_coherence_is_core]

+trait ToOwned {

+ type Owned;

+ fn to_owned(&self) -> Self::Owned;

+struct String;

+impl ToOwned for str {

+ type Owned = String;

+ fn to_owned(&self) -> Self::Owned { String }

+fn a(s: &String) {}

+fn main() {

+ let s = "".to_owned();

+ a(&s)

+"#,

+ );

+ }

}

diff --git a/crates/ide/src/static_index.rs b/crates/ide/src/static_index.rs
index 14b6529c61..8c3275df1b 100644
--- a/crates/ide/src/static_index.rs
+++ b/crates/ide/src/static_index.rs

@@ -169,6 +169,7 @@ impl StaticIndex<'_> {

closure_return_type_hints: crate::ClosureReturnTypeHints::WithBlock,

lifetime_elision_hints: crate::LifetimeElisionHints::Never,

adjustment_hints: crate::AdjustmentHints::Never,

+ adjustment_hints_disable_reborrows: true,

adjustment_hints_mode: AdjustmentHintsMode::Prefix,

adjustment_hints_hide_outside_unsafe: false,

implicit_drop_hints: false,

diff --git a/crates/rust-analyzer/src/cli/analysis_stats.rs b/crates/rust-analyzer/src/cli/analysis_stats.rs
index 6c0aa19f57..b17186f8d7 100644
--- a/crates/rust-analyzer/src/cli/analysis_stats.rs
+++ b/crates/rust-analyzer/src/cli/analysis_stats.rs

@@ -1137,6 +1137,7 @@ impl flags::AnalysisStats {

chaining_hints: true,

adjustment_hints: ide::AdjustmentHints::Always,

+ adjustment_hints_disable_reborrows: true,

adjustment_hints_mode: ide::AdjustmentHintsMode::Postfix,

adjustment_hints_hide_outside_unsafe: false,

closure_return_type_hints: ide::ClosureReturnTypeHints::Always,

diff --git a/crates/rust-analyzer/src/config.rs b/crates/rust-analyzer/src/config.rs
index d4cd56dc55..c2252185a3 100644
--- a/crates/rust-analyzer/src/config.rs
+++ b/crates/rust-analyzer/src/config.rs

@@ -226,6 +226,14 @@ config_data! {

inlayHints_discriminantHints_enable: DiscriminantHintsDef =

DiscriminantHintsDef::Never,

+ /// Disable reborrows in expression adjustments inlay hints.

+ ///

+ /// Reborrows are a pair of a builtin deref then borrow, i.e. `&*`. They are inserted by the compiler but are mostly useless to the programmer.

+ ///

+ /// Note: if the deref is not builtin (an overloaded deref), or the borrow is `&raw const`/`&raw mut`, they are not removed.

+ inlayHints_expressionAdjustmentHints_disableReborrows: bool =

+ true,

/// Show inlay hints for type adjustments.

inlayHints_expressionAdjustmentHints_enable: AdjustmentHintsDef =

AdjustmentHintsDef::Never,

@@ -1888,12 +1896,14 @@ impl Config {

AdjustmentHintsDef::Always => ide::AdjustmentHints::Always,

AdjustmentHintsDef::Never => match self.inlayHints_reborrowHints_enable() {

ReborrowHintsDef::Always | ReborrowHintsDef::Mutable => {

- ide::AdjustmentHints::ReborrowOnly

+ ide::AdjustmentHints::BorrowsOnly

}

ReborrowHintsDef::Never => ide::AdjustmentHints::Never,

- AdjustmentHintsDef::Reborrow => ide::AdjustmentHints::ReborrowOnly,

+ AdjustmentHintsDef::Borrows => ide::AdjustmentHints::BorrowsOnly,

+ adjustment_hints_disable_reborrows: *self

+ .inlayHints_expressionAdjustmentHints_disableReborrows(),

adjustment_hints_mode: match self.inlayHints_expressionAdjustmentHints_mode() {

AdjustmentHintsModeDef::Prefix => ide::AdjustmentHintsMode::Prefix,

AdjustmentHintsModeDef::Postfix => ide::AdjustmentHintsMode::Postfix,

@@ -2822,7 +2832,8 @@ enum ReborrowHintsDef {

#[derive(Serialize, Deserialize, Debug, Clone)]

#[serde(rename_all = "snake_case")]

enum AdjustmentHintsDef {

- Reborrow,

+ #[serde(alias = "Reborrow")]

+ Borrows,

#[serde(with = "true_or_always")]

#[serde(untagged)]

Always,

diff --git a/docs/book/src/configuration_generated.md b/docs/book/src/configuration_generated.md
index 6ee956fe0d..9a51212462 100644
--- a/docs/book/src/configuration_generated.md
+++ b/docs/book/src/configuration_generated.md

@@ -959,6 +959,17 @@ Default: `"never"`

Show enum variant discriminant hints.

+## rust-analyzer.inlayHints.expressionAdjustmentHints.disableReborrows {#inlayHints.expressionAdjustmentHints.disableReborrows}

+Default: `true`

+Disable reborrows in expression adjustments inlay hints.

+Reborrows are a pair of a builtin deref then borrow, i.e. `&*`. They are inserted by the compiler but are mostly useless to the programmer.

+Note: if the deref is not builtin (an overloaded deref), or the borrow is `&raw const`/`&raw mut`, they are not removed.

## rust-analyzer.inlayHints.expressionAdjustmentHints.enable {#inlayHints.expressionAdjustmentHints.enable}

Default: `"never"`

diff --git a/editors/code/package.json b/editors/code/package.json
index 4975ca8586..2b2e25e11c 100644
--- a/editors/code/package.json
+++ b/editors/code/package.json

@@ -2212,6 +2212,16 @@

{

"title": "Inlay Hints",

"properties": {

+ "rust-analyzer.inlayHints.expressionAdjustmentHints.disableReborrows": {

+ "markdownDescription": "Disable reborrows in expression adjustments inlay hints.\n\nReborrows are a pair of a builtin deref then borrow, i.e. `&*`. They are inserted by the compiler but are mostly useless to the programmer.\n\nNote: if the deref is not builtin (an overloaded deref), or the borrow is `&raw const`/`&raw mut`, they are not removed.",

+ "default": true,

+ "type": "boolean"

+ }

+ },

+ {

+ "title": "Inlay Hints",

+ "properties": {

"rust-analyzer.inlayHints.expressionAdjustmentHints.enable": {

"markdownDescription": "Show inlay hints for type adjustments.",

"default": "never",