8 files changed, 95 insertions, 27 deletions

diff --git a/crates/assists/src/handlers/inline_local_variable.rs b/crates/assists/src/handlers/inline_local_variable.rs
index dc798daaa..0e63a60e8 100644
--- a/crates/assists/src/handlers/inline_local_variable.rs
+++ b/crates/assists/src/handlers/inline_local_variable.rs
@@ -79,29 +79,30 @@ pub(crate) fn inline_local_variable(acc: &mut Assists, ctx: &AssistContext) -> O
                 None => return Ok(false),
             };
 
-            Ok(!matches!((&initializer_expr, usage_parent),
+            Ok(!matches!(
+                (&initializer_expr, usage_parent),
                 (ast::Expr::CallExpr(_), _)
-                | (ast::Expr::IndexExpr(_), _)
-                | (ast::Expr::MethodCallExpr(_), _)
-                | (ast::Expr::FieldExpr(_), _)
-                | (ast::Expr::TryExpr(_), _)
-                | (ast::Expr::RefExpr(_), _)
-                | (ast::Expr::Literal(_), _)
-                | (ast::Expr::TupleExpr(_), _)
-                | (ast::Expr::ArrayExpr(_), _)
-                | (ast::Expr::ParenExpr(_), _)
-                | (ast::Expr::PathExpr(_), _)
-                | (ast::Expr::BlockExpr(_), _)
-                | (ast::Expr::EffectExpr(_), _)
-                | (_, ast::Expr::CallExpr(_))
-                | (_, ast::Expr::TupleExpr(_))
-                | (_, ast::Expr::ArrayExpr(_))
-                | (_, ast::Expr::ParenExpr(_))
-                | (_, ast::Expr::ForExpr(_))
-                | (_, ast::Expr::WhileExpr(_))
-                | (_, ast::Expr::BreakExpr(_))
-                | (_, ast::Expr::ReturnExpr(_))
-                | (_, ast::Expr::MatchExpr(_))
+                    | (ast::Expr::IndexExpr(_), _)
+                    | (ast::Expr::MethodCallExpr(_), _)
+                    | (ast::Expr::FieldExpr(_), _)
+                    | (ast::Expr::TryExpr(_), _)
+                    | (ast::Expr::RefExpr(_), _)
+                    | (ast::Expr::Literal(_), _)
+                    | (ast::Expr::TupleExpr(_), _)
+                    | (ast::Expr::ArrayExpr(_), _)
+                    | (ast::Expr::ParenExpr(_), _)
+                    | (ast::Expr::PathExpr(_), _)
+                    | (ast::Expr::BlockExpr(_), _)
+                    | (ast::Expr::EffectExpr(_), _)
+                    | (_, ast::Expr::CallExpr(_))
+                    | (_, ast::Expr::TupleExpr(_))
+                    | (_, ast::Expr::ArrayExpr(_))
+                    | (_, ast::Expr::ParenExpr(_))
+                    | (_, ast::Expr::ForExpr(_))
+                    | (_, ast::Expr::WhileExpr(_))
+                    | (_, ast::Expr::BreakExpr(_))
+                    | (_, ast::Expr::ReturnExpr(_))
+                    | (_, ast::Expr::MatchExpr(_))
             ))
         })
         .collect::<Result<Vec<_>, _>>()?;
diff --git a/crates/hir_def/src/body/lower.rs b/crates/hir_def/src/body/lower.rs
index 27575c537..4ce5e5b72 100644
--- a/crates/hir_def/src/body/lower.rs
+++ b/crates/hir_def/src/body/lower.rs
@@ -386,6 +386,10 @@ impl ExprCollector<'_> {
                 let expr = e.expr().map(|e| self.collect_expr(e));
                 self.alloc_expr(Expr::Return { expr }, syntax_ptr)
             }
+            ast::Expr::YieldExpr(e) => {
+                let expr = e.expr().map(|e| self.collect_expr(e));
+                self.alloc_expr(Expr::Yield { expr }, syntax_ptr)
+            }
             ast::Expr::RecordExpr(e) => {
                 let path = e.path().and_then(|path| self.expander.parse_path(path));
                 let mut field_ptrs = Vec::new();
diff --git a/crates/hir_def/src/expr.rs b/crates/hir_def/src/expr.rs
index af01d32dc..a293df9f1 100644
--- a/crates/hir_def/src/expr.rs
+++ b/crates/hir_def/src/expr.rs
@@ -99,6 +99,9 @@ pub enum Expr {
     Return {
         expr: Option<ExprId>,
     },
+    Yield {
+        expr: Option<ExprId>,
+    },
     RecordLit {
         path: Option<Path>,
         fields: Vec<RecordLitField>,
@@ -294,7 +297,7 @@ impl Expr {
                 }
             }
             Expr::Continue { .. } => {}
-            Expr::Break { expr, .. } | Expr::Return { expr } => {
+            Expr::Break { expr, .. } | Expr::Return { expr } | Expr::Yield { expr } => {
                 if let Some(expr) = expr {
                     f(*expr);
                 }
diff --git a/crates/hir_ty/src/infer/expr.rs b/crates/hir_ty/src/infer/expr.rs
index f2fc69b2f..9bf3b51b0 100644
--- a/crates/hir_ty/src/infer/expr.rs
+++ b/crates/hir_ty/src/infer/expr.rs
@@ -367,6 +367,13 @@ impl<'a> InferenceContext<'a> {
                 }
                 Ty::simple(TypeCtor::Never)
             }
+            Expr::Yield { expr } => {
+                // FIXME: track yield type for coercion
+                if let Some(expr) = expr {
+                    self.infer_expr(*expr, &Expectation::none());
+                }
+                Ty::simple(TypeCtor::Never)
+            }
             Expr::RecordLit { path, fields, spread } => {
                 let (ty, def_id) = self.resolve_variant(path.as_ref());
                 if let Some(variant) = def_id {
diff --git a/crates/parser/src/grammar/expressions/atom.rs b/crates/parser/src/grammar/expressions/atom.rs
index d61950b96..093a9890d 100644
--- a/crates/parser/src/grammar/expressions/atom.rs
+++ b/crates/parser/src/grammar/expressions/atom.rs
@@ -50,6 +50,7 @@ pub(super) const ATOM_EXPR_FIRST: TokenSet =
         T![match],
         T![unsafe],
         T![return],
+        T![yield],
         T![break],
         T![continue],
         T![async],
@@ -142,6 +143,7 @@ pub(super) fn atom_expr(p: &mut Parser, r: Restrictions) -> Option<(CompletedMar
             block_expr_unchecked(p)
         }
         T![return] => return_expr(p),
+        T![yield] => yield_expr(p),
         T![continue] => continue_expr(p),
         T![break] => break_expr(p, r),
         _ => {
@@ -508,6 +510,20 @@ fn return_expr(p: &mut Parser) -> CompletedMarker {
     }
     m.complete(p, RETURN_EXPR)
 }
+// test yield_expr
+// fn foo() {
+//     yield;
+//     yield 1;
+// }
+fn yield_expr(p: &mut Parser) -> CompletedMarker {
+    assert!(p.at(T![yield]));
+    let m = p.start();
+    p.bump(T![yield]);
+    if p.at_ts(EXPR_FIRST) {
+        expr(p);
+    }
+    m.complete(p, YIELD_EXPR)
+}
 
 // test continue_expr
 // fn foo() {
diff --git a/crates/parser/src/syntax_kind/generated.rs b/crates/parser/src/syntax_kind/generated.rs
index f69e71bdb..7d53cc4cd 100644
--- a/crates/parser/src/syntax_kind/generated.rs
+++ b/crates/parser/src/syntax_kind/generated.rs
@@ -101,6 +101,7 @@ pub enum SyntaxKind {
     USE_KW,
     WHERE_KW,
     WHILE_KW,
+    YIELD_KW,
     AUTO_KW,
     DEFAULT_KW,
     EXISTENTIAL_KW,
@@ -186,6 +187,7 @@ pub enum SyntaxKind {
     LABEL,
     BLOCK_EXPR,
     RETURN_EXPR,
+    YIELD_EXPR,
     MATCH_EXPR,
     MATCH_ARM_LIST,
     MATCH_ARM,
@@ -263,7 +265,8 @@ impl SyntaxKind {
             | IMPL_KW | IN_KW | LET_KW | LOOP_KW | MACRO_KW | MATCH_KW | MOD_KW | MOVE_KW
             | MUT_KW | PUB_KW | REF_KW | RETURN_KW | SELF_KW | STATIC_KW | STRUCT_KW | SUPER_KW
             | TRAIT_KW | TRUE_KW | TRY_KW | TYPE_KW | UNSAFE_KW | USE_KW | WHERE_KW | WHILE_KW
-            | AUTO_KW | DEFAULT_KW | EXISTENTIAL_KW | UNION_KW | RAW_KW | MACRO_RULES_KW => true,
+            | YIELD_KW | AUTO_KW | DEFAULT_KW | EXISTENTIAL_KW | UNION_KW | RAW_KW
+            | MACRO_RULES_KW => true,
             _ => false,
         }
     }
@@ -326,6 +329,7 @@ impl SyntaxKind {
             "use" => USE_KW,
             "where" => WHERE_KW,
             "while" => WHILE_KW,
+            "yield" => YIELD_KW,
             _ => return None,
         };
         Some(kw)
@@ -366,4 +370,4 @@ impl SyntaxKind {
     }
 }
 #[macro_export]
-macro_rules ! T { [;] => { $ crate :: SyntaxKind :: SEMICOLON } ; [,] => { $ crate :: SyntaxKind :: COMMA } ; ['('] => { $ crate :: SyntaxKind :: L_PAREN } ; [')'] => { $ crate :: SyntaxKind :: R_PAREN } ; ['{'] => { $ crate :: SyntaxKind :: L_CURLY } ; ['}'] => { $ crate :: SyntaxKind :: R_CURLY } ; ['['] => { $ crate :: SyntaxKind :: L_BRACK } ; [']'] => { $ crate :: SyntaxKind :: R_BRACK } ; [<] => { $ crate :: SyntaxKind :: L_ANGLE } ; [>] => { $ crate :: SyntaxKind :: R_ANGLE } ; [@] => { $ crate :: SyntaxKind :: AT } ; [#] => { $ crate :: SyntaxKind :: POUND } ; [~] => { $ crate :: SyntaxKind :: TILDE } ; [?] => { $ crate :: SyntaxKind :: QUESTION } ; [$] => { $ crate :: SyntaxKind :: DOLLAR } ; [&] => { $ crate :: SyntaxKind :: AMP } ; [|] => { $ crate :: SyntaxKind :: PIPE } ; [+] => { $ crate :: SyntaxKind :: PLUS } ; [*] => { $ crate :: SyntaxKind :: STAR } ; [/] => { $ crate :: SyntaxKind :: SLASH } ; [^] => { $ crate :: SyntaxKind :: CARET } ; [%] => { $ crate :: SyntaxKind :: PERCENT } ; [_] => { $ crate :: SyntaxKind :: UNDERSCORE } ; [.] => { $ crate :: SyntaxKind :: DOT } ; [..] => { $ crate :: SyntaxKind :: DOT2 } ; [...] => { $ crate :: SyntaxKind :: DOT3 } ; [..=] => { $ crate :: SyntaxKind :: DOT2EQ } ; [:] => { $ crate :: SyntaxKind :: COLON } ; [::] => { $ crate :: SyntaxKind :: COLON2 } ; [=] => { $ crate :: SyntaxKind :: EQ } ; [==] => { $ crate :: SyntaxKind :: EQ2 } ; [=>] => { $ crate :: SyntaxKind :: FAT_ARROW } ; [!] => { $ crate :: SyntaxKind :: BANG } ; [!=] => { $ crate :: SyntaxKind :: NEQ } ; [-] => { $ crate :: SyntaxKind :: MINUS } ; [->] => { $ crate :: SyntaxKind :: THIN_ARROW } ; [<=] => { $ crate :: SyntaxKind :: LTEQ } ; [>=] => { $ crate :: SyntaxKind :: GTEQ } ; [+=] => { $ crate :: SyntaxKind :: PLUSEQ } ; [-=] => { $ crate :: SyntaxKind :: MINUSEQ } ; [|=] => { $ crate :: SyntaxKind :: PIPEEQ } ; [&=] => { $ crate :: SyntaxKind :: AMPEQ } ; [^=] => { $ crate :: SyntaxKind :: CARETEQ } ; [/=] => { $ crate :: SyntaxKind :: SLASHEQ } ; [*=] => { $ crate :: SyntaxKind :: STAREQ } ; [%=] => { $ crate :: SyntaxKind :: PERCENTEQ } ; [&&] => { $ crate :: SyntaxKind :: AMP2 } ; [||] => { $ crate :: SyntaxKind :: PIPE2 } ; [<<] => { $ crate :: SyntaxKind :: SHL } ; [>>] => { $ crate :: SyntaxKind :: SHR } ; [<<=] => { $ crate :: SyntaxKind :: SHLEQ } ; [>>=] => { $ crate :: SyntaxKind :: SHREQ } ; [as] => { $ crate :: SyntaxKind :: AS_KW } ; [async] => { $ crate :: SyntaxKind :: ASYNC_KW } ; [await] => { $ crate :: SyntaxKind :: AWAIT_KW } ; [box] => { $ crate :: SyntaxKind :: BOX_KW } ; [break] => { $ crate :: SyntaxKind :: BREAK_KW } ; [const] => { $ crate :: SyntaxKind :: CONST_KW } ; [continue] => { $ crate :: SyntaxKind :: CONTINUE_KW } ; [crate] => { $ crate :: SyntaxKind :: CRATE_KW } ; [dyn] => { $ crate :: SyntaxKind :: DYN_KW } ; [else] => { $ crate :: SyntaxKind :: ELSE_KW } ; [enum] => { $ crate :: SyntaxKind :: ENUM_KW } ; [extern] => { $ crate :: SyntaxKind :: EXTERN_KW } ; [false] => { $ crate :: SyntaxKind :: FALSE_KW } ; [fn] => { $ crate :: SyntaxKind :: FN_KW } ; [for] => { $ crate :: SyntaxKind :: FOR_KW } ; [if] => { $ crate :: SyntaxKind :: IF_KW } ; [impl] => { $ crate :: SyntaxKind :: IMPL_KW } ; [in] => { $ crate :: SyntaxKind :: IN_KW } ; [let] => { $ crate :: SyntaxKind :: LET_KW } ; [loop] => { $ crate :: SyntaxKind :: LOOP_KW } ; [macro] => { $ crate :: SyntaxKind :: MACRO_KW } ; [match] => { $ crate :: SyntaxKind :: MATCH_KW } ; [mod] => { $ crate :: SyntaxKind :: MOD_KW } ; [move] => { $ crate :: SyntaxKind :: MOVE_KW } ; [mut] => { $ crate :: SyntaxKind :: MUT_KW } ; [pub] => { $ crate :: SyntaxKind :: PUB_KW } ; [ref] => { $ crate :: SyntaxKind :: REF_KW } ; [return] => { $ crate :: SyntaxKind :: RETURN_KW } ; [self] => { $ crate :: SyntaxKind :: SELF_KW } ; [static] => { $ crate :: SyntaxKind :: STATIC_KW } ; [struct] => { $ crate :: SyntaxKind :: STRUCT_KW } ; [super] => { $ crate :: SyntaxKind :: SUPER_KW } ; [trait] => { $ crate :: SyntaxKind :: TRAIT_KW } ; [true] => { $ crate :: SyntaxKind :: TRUE_KW } ; [try] => { $ crate :: SyntaxKind :: TRY_KW } ; [type] => { $ crate :: SyntaxKind :: TYPE_KW } ; [unsafe] => { $ crate :: SyntaxKind :: UNSAFE_KW } ; [use] => { $ crate :: SyntaxKind :: USE_KW } ; [where] => { $ crate :: SyntaxKind :: WHERE_KW } ; [while] => { $ crate :: SyntaxKind :: WHILE_KW } ; [auto] => { $ crate :: SyntaxKind :: AUTO_KW } ; [default] => { $ crate :: SyntaxKind :: DEFAULT_KW } ; [existential] => { $ crate :: SyntaxKind :: EXISTENTIAL_KW } ; [union] => { $ crate :: SyntaxKind :: UNION_KW } ; [raw] => { $ crate :: SyntaxKind :: RAW_KW } ; [macro_rules] => { $ crate :: SyntaxKind :: MACRO_RULES_KW } ; [lifetime_ident] => { $ crate :: SyntaxKind :: LIFETIME_IDENT } ; [ident] => { $ crate :: SyntaxKind :: IDENT } ; [shebang] => { $ crate :: SyntaxKind :: SHEBANG } ; }
+macro_rules ! T { [;] => { $ crate :: SyntaxKind :: SEMICOLON } ; [,] => { $ crate :: SyntaxKind :: COMMA } ; ['('] => { $ crate :: SyntaxKind :: L_PAREN } ; [')'] => { $ crate :: SyntaxKind :: R_PAREN } ; ['{'] => { $ crate :: SyntaxKind :: L_CURLY } ; ['}'] => { $ crate :: SyntaxKind :: R_CURLY } ; ['['] => { $ crate :: SyntaxKind :: L_BRACK } ; [']'] => { $ crate :: SyntaxKind :: R_BRACK } ; [<] => { $ crate :: SyntaxKind :: L_ANGLE } ; [>] => { $ crate :: SyntaxKind :: R_ANGLE } ; [@] => { $ crate :: SyntaxKind :: AT } ; [#] => { $ crate :: SyntaxKind :: POUND } ; [~] => { $ crate :: SyntaxKind :: TILDE } ; [?] => { $ crate :: SyntaxKind :: QUESTION } ; [$] => { $ crate :: SyntaxKind :: DOLLAR } ; [&] => { $ crate :: SyntaxKind :: AMP } ; [|] => { $ crate :: SyntaxKind :: PIPE } ; [+] => { $ crate :: SyntaxKind :: PLUS } ; [*] => { $ crate :: SyntaxKind :: STAR } ; [/] => { $ crate :: SyntaxKind :: SLASH } ; [^] => { $ crate :: SyntaxKind :: CARET } ; [%] => { $ crate :: SyntaxKind :: PERCENT } ; [_] => { $ crate :: SyntaxKind :: UNDERSCORE } ; [.] => { $ crate :: SyntaxKind :: DOT } ; [..] => { $ crate :: SyntaxKind :: DOT2 } ; [...] => { $ crate :: SyntaxKind :: DOT3 } ; [..=] => { $ crate :: SyntaxKind :: DOT2EQ } ; [:] => { $ crate :: SyntaxKind :: COLON } ; [::] => { $ crate :: SyntaxKind :: COLON2 } ; [=] => { $ crate :: SyntaxKind :: EQ } ; [==] => { $ crate :: SyntaxKind :: EQ2 } ; [=>] => { $ crate :: SyntaxKind :: FAT_ARROW } ; [!] => { $ crate :: SyntaxKind :: BANG } ; [!=] => { $ crate :: SyntaxKind :: NEQ } ; [-] => { $ crate :: SyntaxKind :: MINUS } ; [->] => { $ crate :: SyntaxKind :: THIN_ARROW } ; [<=] => { $ crate :: SyntaxKind :: LTEQ } ; [>=] => { $ crate :: SyntaxKind :: GTEQ } ; [+=] => { $ crate :: SyntaxKind :: PLUSEQ } ; [-=] => { $ crate :: SyntaxKind :: MINUSEQ } ; [|=] => { $ crate :: SyntaxKind :: PIPEEQ } ; [&=] => { $ crate :: SyntaxKind :: AMPEQ } ; [^=] => { $ crate :: SyntaxKind :: CARETEQ } ; [/=] => { $ crate :: SyntaxKind :: SLASHEQ } ; [*=] => { $ crate :: SyntaxKind :: STAREQ } ; [%=] => { $ crate :: SyntaxKind :: PERCENTEQ } ; [&&] => { $ crate :: SyntaxKind :: AMP2 } ; [||] => { $ crate :: SyntaxKind :: PIPE2 } ; [<<] => { $ crate :: SyntaxKind :: SHL } ; [>>] => { $ crate :: SyntaxKind :: SHR } ; [<<=] => { $ crate :: SyntaxKind :: SHLEQ } ; [>>=] => { $ crate :: SyntaxKind :: SHREQ } ; [as] => { $ crate :: SyntaxKind :: AS_KW } ; [async] => { $ crate :: SyntaxKind :: ASYNC_KW } ; [await] => { $ crate :: SyntaxKind :: AWAIT_KW } ; [box] => { $ crate :: SyntaxKind :: BOX_KW } ; [break] => { $ crate :: SyntaxKind :: BREAK_KW } ; [const] => { $ crate :: SyntaxKind :: CONST_KW } ; [continue] => { $ crate :: SyntaxKind :: CONTINUE_KW } ; [crate] => { $ crate :: SyntaxKind :: CRATE_KW } ; [dyn] => { $ crate :: SyntaxKind :: DYN_KW } ; [else] => { $ crate :: SyntaxKind :: ELSE_KW } ; [enum] => { $ crate :: SyntaxKind :: ENUM_KW } ; [extern] => { $ crate :: SyntaxKind :: EXTERN_KW } ; [false] => { $ crate :: SyntaxKind :: FALSE_KW } ; [fn] => { $ crate :: SyntaxKind :: FN_KW } ; [for] => { $ crate :: SyntaxKind :: FOR_KW } ; [if] => { $ crate :: SyntaxKind :: IF_KW } ; [impl] => { $ crate :: SyntaxKind :: IMPL_KW } ; [in] => { $ crate :: SyntaxKind :: IN_KW } ; [let] => { $ crate :: SyntaxKind :: LET_KW } ; [loop] => { $ crate :: SyntaxKind :: LOOP_KW } ; [macro] => { $ crate :: SyntaxKind :: MACRO_KW } ; [match] => { $ crate :: SyntaxKind :: MATCH_KW } ; [mod] => { $ crate :: SyntaxKind :: MOD_KW } ; [move] => { $ crate :: SyntaxKind :: MOVE_KW } ; [mut] => { $ crate :: SyntaxKind :: MUT_KW } ; [pub] => { $ crate :: SyntaxKind :: PUB_KW } ; [ref] => { $ crate :: SyntaxKind :: REF_KW } ; [return] => { $ crate :: SyntaxKind :: RETURN_KW } ; [self] => { $ crate :: SyntaxKind :: SELF_KW } ; [static] => { $ crate :: SyntaxKind :: STATIC_KW } ; [struct] => { $ crate :: SyntaxKind :: STRUCT_KW } ; [super] => { $ crate :: SyntaxKind :: SUPER_KW } ; [trait] => { $ crate :: SyntaxKind :: TRAIT_KW } ; [true] => { $ crate :: SyntaxKind :: TRUE_KW } ; [try] => { $ crate :: SyntaxKind :: TRY_KW } ; [type] => { $ crate :: SyntaxKind :: TYPE_KW } ; [unsafe] => { $ crate :: SyntaxKind :: UNSAFE_KW } ; [use] => { $ crate :: SyntaxKind :: USE_KW } ; [where] => { $ crate :: SyntaxKind :: WHERE_KW } ; [while] => { $ crate :: SyntaxKind :: WHILE_KW } ; [yield] => { $ crate :: SyntaxKind :: YIELD_KW } ; [auto] => { $ crate :: SyntaxKind :: AUTO_KW } ; [default] => { $ crate :: SyntaxKind :: DEFAULT_KW } ; [existential] => { $ crate :: SyntaxKind :: EXISTENTIAL_KW } ; [union] => { $ crate :: SyntaxKind :: UNION_KW } ; [raw] => { $ crate :: SyntaxKind :: RAW_KW } ; [macro_rules] => { $ crate :: SyntaxKind :: MACRO_RULES_KW } ; [lifetime_ident] => { $ crate :: SyntaxKind :: LIFETIME_IDENT } ; [ident] => { $ crate :: SyntaxKind :: IDENT } ; [shebang] => { $ crate :: SyntaxKind :: SHEBANG } ; }
diff --git a/crates/syntax/src/ast/generated/nodes.rs b/crates/syntax/src/ast/generated/nodes.rs
index 92ed2ee9d..9c96d3d07 100644
--- a/crates/syntax/src/ast/generated/nodes.rs
+++ b/crates/syntax/src/ast/generated/nodes.rs
@@ -931,6 +931,15 @@ impl WhileExpr {
     pub fn condition(&self) -> Option<Condition> { support::child(&self.syntax) }
 }
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct YieldExpr {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ast::AttrsOwner for YieldExpr {}
+impl YieldExpr {
+    pub fn yield_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![yield]) }
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+}
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct Label {
     pub(crate) syntax: SyntaxNode,
 }
@@ -1334,6 +1343,7 @@ pub enum Expr {
     TryExpr(TryExpr),
     TupleExpr(TupleExpr),
     WhileExpr(WhileExpr),
+    YieldExpr(YieldExpr),
 }
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub enum Item {
@@ -2386,6 +2396,17 @@ impl AstNode for WhileExpr {
     }
     fn syntax(&self) -> &SyntaxNode { &self.syntax }
 }
+impl AstNode for YieldExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == YIELD_EXPR }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
 impl AstNode for Label {
     fn can_cast(kind: SyntaxKind) -> bool { kind == LABEL }
     fn cast(syntax: SyntaxNode) -> Option<Self> {
@@ -3028,6 +3049,9 @@ impl From<TupleExpr> for Expr {
 impl From<WhileExpr> for Expr {
     fn from(node: WhileExpr) -> Expr { Expr::WhileExpr(node) }
 }
+impl From<YieldExpr> for Expr {
+    fn from(node: YieldExpr) -> Expr { Expr::YieldExpr(node) }
+}
 impl AstNode for Expr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -3035,7 +3059,8 @@ impl AstNode for Expr {
             | CAST_EXPR | CLOSURE_EXPR | CONTINUE_EXPR | EFFECT_EXPR | FIELD_EXPR | FOR_EXPR
             | IF_EXPR | INDEX_EXPR | LITERAL | LOOP_EXPR | MACRO_CALL | MATCH_EXPR
             | METHOD_CALL_EXPR | PAREN_EXPR | PATH_EXPR | PREFIX_EXPR | RANGE_EXPR
-            | RECORD_EXPR | REF_EXPR | RETURN_EXPR | TRY_EXPR | TUPLE_EXPR | WHILE_EXPR => true,
+            | RECORD_EXPR | REF_EXPR | RETURN_EXPR | TRY_EXPR | TUPLE_EXPR | WHILE_EXPR
+            | YIELD_EXPR => true,
             _ => false,
         }
     }
@@ -3071,6 +3096,7 @@ impl AstNode for Expr {
             TRY_EXPR => Expr::TryExpr(TryExpr { syntax }),
             TUPLE_EXPR => Expr::TupleExpr(TupleExpr { syntax }),
             WHILE_EXPR => Expr::WhileExpr(WhileExpr { syntax }),
+            YIELD_EXPR => Expr::YieldExpr(YieldExpr { syntax }),
             _ => return None,
         };
         Some(res)
@@ -3107,6 +3133,7 @@ impl AstNode for Expr {
             Expr::TryExpr(it) => &it.syntax,
             Expr::TupleExpr(it) => &it.syntax,
             Expr::WhileExpr(it) => &it.syntax,
+            Expr::YieldExpr(it) => &it.syntax,
         }
     }
 }
@@ -3983,6 +4010,11 @@ impl std::fmt::Display for WhileExpr {
         std::fmt::Display::fmt(self.syntax(), f)
     }
 }
+impl std::fmt::Display for YieldExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl std::fmt::Display for Label {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         std::fmt::Display::fmt(self.syntax(), f)
diff --git a/xtask/src/ast_src.rs b/xtask/src/ast_src.rs
index 2b8012bdd..046d68f52 100644
--- a/xtask/src/ast_src.rs
+++ b/xtask/src/ast_src.rs
@@ -68,7 +68,7 @@ pub(crate) const KINDS_SRC: KindsSrc = KindsSrc {
         "as", "async", "await", "box", "break", "const", "continue", "crate", "dyn", "else",
         "enum", "extern", "false", "fn", "for", "if", "impl", "in", "let", "loop", "macro",
         "match", "mod", "move", "mut", "pub", "ref", "return", "self", "static", "struct", "super",
-        "trait", "true", "try", "type", "unsafe", "use", "where", "while",
+        "trait", "true", "try", "type", "unsafe", "use", "where", "while", "yield",
     ],
     contextual_keywords: &["auto", "default", "existential", "union", "raw", "macro_rules"],
     literals: &["INT_NUMBER", "FLOAT_NUMBER", "CHAR", "BYTE", "STRING", "BYTE_STRING"],
@@ -149,6 +149,7 @@ pub(crate) const KINDS_SRC: KindsSrc = KindsSrc {
         "LABEL",
         "BLOCK_EXPR",
         "RETURN_EXPR",
+        "YIELD_EXPR",
         "MATCH_EXPR",
         "MATCH_ARM_LIST",
         "MATCH_ARM",