rust-analyzer

diff --git a/crates/hir-def/src/body/lower.rs b/crates/hir-def/src/body/lower.rs
index 152c02743f..c8d1ca4fa7 100644
--- a/crates/hir-def/src/body/lower.rs
+++ b/crates/hir-def/src/body/lower.rs

@@ -314,11 +314,18 @@ impl ExprCollector<'_> {

self.alloc_expr(Expr::Loop { body, label }, syntax_ptr)

}

ast::Expr::WhileExpr(e) => {

+ // Desugar `while <cond> { <body> }` to

+ // `loop { if <cond> { <body> } else { break } }`

let label = e.label().map(|label| self.collect_label(label));

let body = self.collect_labelled_block_opt(label, e.loop_body());

let condition = self.collect_expr_opt(e.condition());

- self.alloc_expr(Expr::While { condition, body, label }, syntax_ptr)

+ let break_expr =

+ self.alloc_expr(Expr::Break { expr: None, label: None }, syntax_ptr.clone());

+ let if_expr = self.alloc_expr(

+ Expr::If { condition, then_branch: body, else_branch: Some(break_expr) },

+ syntax_ptr.clone(),

+ );

+ self.alloc_expr(Expr::Loop { body: if_expr, label }, syntax_ptr)

}

ast::Expr::ForExpr(e) => self.collect_for_loop(syntax_ptr, e),

ast::Expr::CallExpr(e) => {

diff --git a/crates/hir-def/src/body/pretty.rs b/crates/hir-def/src/body/pretty.rs
index eeaed87164..5d71abe37c 100644
--- a/crates/hir-def/src/body/pretty.rs
+++ b/crates/hir-def/src/body/pretty.rs

@@ -178,14 +178,6 @@ impl Printer<'_> {

w!(self, "loop ");

self.print_expr(*body);

}

- Expr::While { condition, body, label } => {

- if let Some(lbl) = label {

- w!(self, "{}: ", self.body[*lbl].name.display(self.db));

- }

- w!(self, "while ");

- self.print_expr(*condition);

- self.print_expr(*body);

- }

Expr::Call { callee, args, is_assignee_expr: _ } => {

self.print_expr(*callee);

w!(self, "(");

diff --git a/crates/hir-def/src/body/scope.rs b/crates/hir-def/src/body/scope.rs
index 69741c445f..2a90a09f25 100644
--- a/crates/hir-def/src/body/scope.rs
+++ b/crates/hir-def/src/body/scope.rs

@@ -228,11 +228,6 @@ fn compute_expr_scopes(expr: ExprId, body: &Body, scopes: &mut ExprScopes, scope

scopes.set_scope(expr, scope);

compute_block_scopes(statements, *tail, body, scopes, &mut scope);

}

- Expr::While { condition, body: body_expr, label } => {

- let mut scope = scopes.new_labeled_scope(*scope, make_label(label));

- compute_expr_scopes(*condition, body, scopes, &mut scope);

- compute_expr_scopes(*body_expr, body, scopes, &mut scope);

- }

Expr::Loop { body: body_expr, label } => {

let mut scope = scopes.new_labeled_scope(*scope, make_label(label));

compute_expr_scopes(*body_expr, body, scopes, &mut scope);

diff --git a/crates/hir-def/src/hir.rs b/crates/hir-def/src/hir.rs
index 8a140a1ec1..6591c92ac6 100644
--- a/crates/hir-def/src/hir.rs
+++ b/crates/hir-def/src/hir.rs

@@ -191,11 +191,6 @@ pub enum Expr {

body: ExprId,

label: Option<LabelId>,

- While {

- condition: ExprId,

- body: ExprId,

- label: Option<LabelId>,

- },

Call {

callee: ExprId,

args: Box<[ExprId]>,

@@ -379,10 +374,6 @@ impl Expr {

}

Expr::Loop { body, .. } => f(*body),

- Expr::While { condition, body, .. } => {

- f(*condition);

- f(*body);

- }

Expr::Call { callee, args, .. } => {

f(*callee);

args.iter().copied().for_each(f);

diff --git a/crates/hir-ty/src/infer/closure.rs b/crates/hir-ty/src/infer/closure.rs
index 972e5321a4..1781f6c58f 100644
--- a/crates/hir-ty/src/infer/closure.rs
+++ b/crates/hir-ty/src/infer/closure.rs

@@ -488,10 +488,6 @@ impl InferenceContext<'_> {

self.consume_expr(*tail);

}

- Expr::While { condition, body, label: _ } => {

- self.consume_expr(*condition);

- self.consume_expr(*body);

- }

Expr::Call { callee, args, is_assignee_expr: _ } => {

self.consume_expr(*callee);

self.consume_exprs(args.iter().copied());

diff --git a/crates/hir-ty/src/infer/expr.rs b/crates/hir-ty/src/infer/expr.rs
index 501c0b4bd7..8cbdae6252 100644
--- a/crates/hir-ty/src/infer/expr.rs
+++ b/crates/hir-ty/src/infer/expr.rs

@@ -198,19 +198,6 @@ impl InferenceContext<'_> {

None => self.result.standard_types.never.clone(),

}

- &Expr::While { condition, body, label } => {

- self.with_breakable_ctx(BreakableKind::Loop, None, label, |this| {

- this.infer_expr(

- condition,

- &Expectation::HasType(this.result.standard_types.bool_.clone()),

- );

- this.infer_expr(body, &Expectation::HasType(TyBuilder::unit()));

- });

- // the body may not run, so it diverging doesn't mean we diverge

- self.diverges = Diverges::Maybe;

- TyBuilder::unit()

- }

Expr::Closure { body, args, ret_type, arg_types, closure_kind, capture_by: _ } => {

assert_eq!(args.len(), arg_types.len());

diff --git a/crates/hir-ty/src/infer/mutability.rs b/crates/hir-ty/src/infer/mutability.rs
index f517bc2c09..396ca0044f 100644
--- a/crates/hir-ty/src/infer/mutability.rs
+++ b/crates/hir-ty/src/infer/mutability.rs

@@ -69,10 +69,6 @@ impl InferenceContext<'_> {

self.infer_mut_expr(*tail, Mutability::Not);

}

- &Expr::While { condition: c, body, label: _ } => {

- self.infer_mut_expr(c, Mutability::Not);

- self.infer_mut_expr(body, Mutability::Not);

- }

Expr::MethodCall { receiver: it, method_name: _, args, generic_args: _ }

| Expr::Call { callee: it, args, is_assignee_expr: _ } => {

self.infer_mut_not_expr_iter(args.iter().copied().chain(Some(*it)));

diff --git a/crates/hir-ty/src/mir/lower.rs b/crates/hir-ty/src/mir/lower.rs
index e5e8909481..718df8331e 100644
--- a/crates/hir-ty/src/mir/lower.rs
+++ b/crates/hir-ty/src/mir/lower.rs

@@ -582,36 +582,6 @@ impl<'ctx> MirLowerCtx<'ctx> {

Ok(())

})

}

- Expr::While { condition, body, label } => {

- self.lower_loop(current, place, *label, expr_id.into(), |this, begin| {

- let scope = this.push_drop_scope();

- let Some((discr, to_switch)) =

- this.lower_expr_to_some_operand(*condition, begin)?

- else {

- return Ok(());

- };

- let fail_cond = this.new_basic_block();

- let after_cond = this.new_basic_block();

- this.set_terminator(

- to_switch,

- TerminatorKind::SwitchInt {

- discr,

- targets: SwitchTargets::static_if(1, after_cond, fail_cond),

- },

- expr_id.into(),

- );

- let fail_cond = this.drop_until_scope(this.drop_scopes.len() - 1, fail_cond);

- let end = this.current_loop_end()?;

- this.set_goto(fail_cond, end, expr_id.into());

- if let Some((_, block)) = this.lower_expr_as_place(after_cond, *body, true)? {

- let block = scope.pop_and_drop(this, block);

- this.set_goto(block, begin, expr_id.into());

- } else {

- scope.pop_assume_dropped(this);

- }

- Ok(())

- })

- }

Expr::Call { callee, args, .. } => {

if let Some((func_id, generic_args)) = self.infer.method_resolution(expr_id) {

let ty = chalk_ir::TyKind::FnDef(

diff --git a/crates/hir-ty/src/tests/macros.rs b/crates/hir-ty/src/tests/macros.rs
index b71c457f01..1e6e946a13 100644
--- a/crates/hir-ty/src/tests/macros.rs
+++ b/crates/hir-ty/src/tests/macros.rs

@@ -209,6 +209,8 @@ fn expr_macro_def_expanded_in_various_places() {

104..105 '_': IntoIterator::Item<isize>

117..119 '{}': ()

124..134 '|| spam!()': impl Fn() -> isize

+ 140..156 'while ...!() {}': !

+ 140..156 'while ...!() {}': ()

140..156 'while ...!() {}': ()

154..156 '{}': ()

161..174 'break spam!()': !

@@ -300,6 +302,8 @@ fn expr_macro_rules_expanded_in_various_places() {

118..119 '_': IntoIterator::Item<isize>

131..133 '{}': ()

138..148 '|| spam!()': impl Fn() -> isize

+ 154..170 'while ...!() {}': !

+ 154..170 'while ...!() {}': ()

154..170 'while ...!() {}': ()

168..170 '{}': ()

175..188 'break spam!()': !

diff --git a/crates/hir-ty/src/tests/never_type.rs b/crates/hir-ty/src/tests/never_type.rs
index 59046c0435..5d809b8239 100644
--- a/crates/hir-ty/src/tests/never_type.rs
+++ b/crates/hir-ty/src/tests/never_type.rs

@@ -412,17 +412,23 @@ fn diverging_expression_3_break() {

355..654 '{ ...; }; }': ()

398..399 'x': u32

407..433 '{ whil...; }; }': u32

+ 409..430 'while ...eak; }': !

+ 409..430 'while ...eak; }': ()

409..430 'while ...eak; }': ()

415..419 'true': bool

420..430 '{ break; }': ()

422..427 'break': !

537..538 'x': u32

546..564 '{ whil... {}; }': u32

+ 548..561 'while true {}': !

+ 548..561 'while true {}': ()

548..561 'while true {}': ()

554..558 'true': bool

559..561 '{}': ()

615..616 'x': u32

624..651 '{ whil...; }; }': u32

+ 626..648 'while ...urn; }': !

+ 626..648 'while ...urn; }': ()

626..648 'while ...urn; }': ()

632..636 'true': bool

637..648 '{ return; }': ()

diff --git a/crates/hir-ty/src/tests/regression.rs b/crates/hir-ty/src/tests/regression.rs
index 375014d6c7..6ea059065e 100644
--- a/crates/hir-ty/src/tests/regression.rs
+++ b/crates/hir-ty/src/tests/regression.rs

@@ -1267,6 +1267,8 @@ fn test() {

"#,

expect![[r#"

10..59 '{ ... } }': ()

+ 16..57 'while ... }': !

+ 16..57 'while ... }': ()

16..57 'while ... }': ()

22..30 '{ true }': bool

24..28 'true': bool