unsafe expr parsing

Author: Grant Wuerker

crates/hir/src/hir_def/expr.rs

@@ -40,6 +40,8 @@ pub enum Expr {
     /// The first `ExprId` is the scrutinee, the second is the arms.
     Match(ExprId, Partial<Vec<MatchArm>>),
 
+    Unsafe(ExprId),
+
     /// The `Assign` Expression. The first `ExprId` is the destination of the assignment,
     /// and the second `ExprId` is the rhs value of the binding.
     Assign(ExprId, ExprId),

crates/hir/src/lower/expr.rs

@@ -172,6 +172,11 @@ impl Expr {
                 Self::Match(scrutinee, arm)
             }
 
+            ast::ExprKind::Unsafe(unsafe_expr) => {
+                let inner = Self::push_to_body_opt(ctxt, unsafe_expr.inner_expr());
+                Self::Unsafe(inner)
+            }
+
             ast::ExprKind::Paren(paren) => {
                 return Self::push_to_body_opt(ctxt, paren.expr());
             }

crates/hir/src/span/expr.rs

@@ -199,6 +199,14 @@ define_lazy_span_node!(
 
 define_lazy_span_node!(LazyMatchArmSpan);
 
+define_lazy_span_node!(
+    LazyUnsafeExprSpan,
+    ast::UnsafeExpr,
+    @token {
+        (unsafe_kw, unsafe_kw),
+    }
+);
+
 #[derive(Clone, Copy, PartialEq, Eq, Hash, Debug)]
 pub(crate) struct ExprRoot {
     expr: ExprId,

crates/hir/src/visitor.rs

@@ -1087,6 +1087,10 @@ where
             }
         }
 
+        Expr::Unsafe(expr_id) => {
+            visit_node_in_body!(visitor, ctxt, expr_id, expr);
+        }
+
         Expr::Assign(left_expr_id, right_expr_id) => {
             visit_node_in_body!(visitor, ctxt, left_expr_id, expr);
             visit_node_in_body!(visitor, ctxt, right_expr_id, expr);

crates/parser2/src/ast/expr.rs

@@ -22,6 +22,7 @@ ast_node! {
     | SK::LitExpr
     | SK::IfExpr
     | SK::MatchExpr
+    | SK::UnsafeExpr
     | SK::ParenExpr
     | SK::AssignExpr
     | SK::AugAssignExpr,
@@ -50,6 +51,7 @@ impl Expr {
             SK::LitExpr => ExprKind::Lit(AstNode::cast(self.syntax().clone()).unwrap()),
             SK::IfExpr => ExprKind::If(AstNode::cast(self.syntax().clone()).unwrap()),
             SK::MatchExpr => ExprKind::Match(AstNode::cast(self.syntax().clone()).unwrap()),
+            SK::UnsafeExpr => ExprKind::Unsafe(AstNode::cast(self.syntax().clone()).unwrap()),
             SK::ParenExpr => ExprKind::Paren(AstNode::cast(self.syntax().clone()).unwrap()),
             SK::AssignExpr => ExprKind::Assign(AstNode::cast(self.syntax().clone()).unwrap()),
             SK::AugAssignExpr => ExprKind::AugAssign(AstNode::cast(self.syntax().clone()).unwrap()),
@@ -326,6 +328,21 @@ impl MatchExpr {
     }
 }
 
+ast_node! {
+    /// `unsafe expr`
+    pub struct UnsafeExpr,
+    SK::UnsafeExpr
+}
+impl UnsafeExpr {
+    pub fn unsafe_kw(&self) -> Option<SyntaxToken> {
+        support::token(self.syntax(), SK::UnsafeKw)
+    }
+
+    pub fn inner_expr(&self) -> Option<Expr> {
+        support::child(self.syntax())
+    }
+}
+
 ast_node! {
     /// `(expr)`
     pub struct ParenExpr,
@@ -398,6 +415,7 @@ pub enum ExprKind {
     ArrayRep(ArrayRepExpr),
     If(IfExpr),
     Match(MatchExpr),
+    Unsafe(UnsafeExpr),
     Paren(ParenExpr),
     Assign(AssignExpr),
     AugAssign(AugAssignExpr),

crates/parser2/src/parser/expr_atom.rs

@@ -22,7 +22,7 @@ use super::{
 pub(super) fn is_expr_atom_head(kind: SyntaxKind) -> bool {
     use SyntaxKind::*;
     match kind {
-        IfKw | MatchKw | LBrace | LParen | LBracket => true,
+        IfKw | MatchKw | LBrace | LParen | LBracket | UnsafeKw => true,
         kind if lit::is_lit(kind) => true,
         kind if path::is_path_segment(kind) => true,
         _ => false,
@@ -38,6 +38,7 @@ pub(super) fn parse_expr_atom<S: TokenStream>(
     match parser.current_kind() {
         Some(IfKw) => parser.parse_cp(IfExprScope::default(), None),
         Some(MatchKw) => parser.parse_cp(MatchExprScope::default(), None),
+        Some(UnsafeKw) => parser.parse_cp(UnsafeExprScope::default(), None),
         Some(LBrace) => parser.parse_cp(BlockExprScope::default(), None),
         Some(LParen) => parser.parse_cp(ParenScope::default(), None),
         Some(LBracket) => parser.parse_cp(ArrayScope::default(), None),
@@ -83,8 +84,22 @@ impl super::Parse for BlockExprScope {
                 .map(SyntaxKind::is_item_head)
                 .unwrap_or_default()
             {
-                parser.parse(ItemScope::default())?;
-                continue;
+                let is_item = parser.dry_run(|parser| {
+                    if parser.bump_if(SyntaxKind::UnsafeKw) {
+                        parser
+                            .current_kind()
+                            .map(SyntaxKind::is_item_head)
+                            .unwrap_or_default()
+                            && !parser.bump_if(SyntaxKind::UnsafeKw)
+                    } else {
+                        true
+                    }
+                });
+
+                if is_item {
+                    parser.parse(ItemScope::default())?;
+                    continue;
+                }
             }
 
             parse_stmt(parser)?;
@@ -131,6 +146,17 @@ impl super::Parse for IfExprScope {
     }
 }
 
+define_scope! { UnsafeExprScope, UnsafeExpr }
+impl super::Parse for UnsafeExprScope {
+    type Error = Recovery<ErrProof>;
+
+    fn parse<S: TokenStream>(&mut self, parser: &mut Parser<S>) -> Result<(), Self::Error> {
+        parser.bump_expected(SyntaxKind::UnsafeKw);
+
+        parse_expr(parser)
+    }
+}
+
 define_scope! { MatchExprScope, MatchExpr }
 impl super::Parse for MatchExprScope {
     type Error = Recovery<ErrProof>;

crates/parser2/src/syntax_kind.rs

@@ -282,6 +282,8 @@ pub enum SyntaxKind {
     LitExpr,
     /// `if x { 1 } else { 2 }`
     IfExpr,
+    /// `unsafe foo(x)`
+    UnsafeExpr,
     /// `match x { pat => { .. } }`
     MatchExpr,
     /// `(1 + 2)`
@@ -571,6 +573,7 @@ impl SyntaxKind {
             SyntaxKind::ConstKw => "`const`",
             SyntaxKind::IfKw => "`if`",
             SyntaxKind::ElseKw => "`else`",
+            SyntaxKind::UnsafeKw => "`unsafe`",
             SyntaxKind::MatchKw => "`match`",
             SyntaxKind::ForKw => "`for`",
             SyntaxKind::InKw => "`in`",
@@ -589,7 +592,6 @@ impl SyntaxKind {
             SyntaxKind::MutKw => "`mut`",
             SyntaxKind::UseKw => "`use`",
             SyntaxKind::ExternKw => "`extern`",
-            SyntaxKind::UnsafeKw => "`unsafe`",
             SyntaxKind::IngotKw => "`ingot`",
             SyntaxKind::SuperKw => "`super`",
             SyntaxKind::LShift => "`<<`",
@@ -632,6 +634,7 @@ impl SyntaxKind {
             SyntaxKind::ArrayRepExpr => "array expression",
             SyntaxKind::LitExpr => "literal expression",
             SyntaxKind::IfExpr => "`if` expression",
+            SyntaxKind::UnsafeExpr => "`unsafe` expression",
             SyntaxKind::MatchExpr => "`match` expression",
             SyntaxKind::ParenExpr => "parenthesized expression",
             SyntaxKind::AssignExpr => "assignment expression",

crates/parser2/test_files/syntax_node/exprs/unsafe.fe

@@ -0,0 +1,11 @@
+unsafe { foo() }
+
+unsafe {
+    let a = 42
+    std::evm::mstore(offset: 0, value: a)
+    return
+}
+
+unsafe 1 + 1
+
+unsafe bar()

crates/parser2/test_files/syntax_node/exprs/unsafe.snap

@@ -0,0 +1,112 @@
+---
+source: crates/parser2/tests/syntax_node.rs
+expression: node
+input_file: crates/parser2/test_files/syntax_node/exprs/unsafe.fe
+---
+Root@0..125
+  UnsafeExpr@0..16
+    UnsafeKw@0..6 "unsafe"
+    WhiteSpace@6..7 " "
+    BlockExpr@7..16
+      LBrace@7..8 "{"
+      WhiteSpace@8..9 " "
+      ExprStmt@9..14
+        CallExpr@9..14
+          PathExpr@9..12
+            Path@9..12
+              PathSegment@9..12
+                Ident@9..12 "foo"
+          CallArgList@12..14
+            LParen@12..13 "("
+            RParen@13..14 ")"
+      WhiteSpace@14..15 " "
+      RBrace@15..16 "}"
+  Newline@16..18 "\n\n"
+  UnsafeExpr@18..96
+    UnsafeKw@18..24 "unsafe"
+    WhiteSpace@24..25 " "
+    BlockExpr@25..96
+      LBrace@25..26 "{"
+      Newline@26..27 "\n"
+      WhiteSpace@27..31 "    "
+      LetStmt@31..41
+        LetKw@31..34 "let"
+        WhiteSpace@34..35 " "
+        PathPat@35..36
+          Path@35..36
+            PathSegment@35..36
+              Ident@35..36 "a"
+        WhiteSpace@36..37 " "
+        Eq@37..38 "="
+        WhiteSpace@38..39 " "
+        LitExpr@39..41
+          Lit@39..41
+            Int@39..41 "42"
+      Newline@41..42 "\n"
+      WhiteSpace@42..46 "    "
+      ExprStmt@46..83
+        CallExpr@46..83
+          PathExpr@46..62
+            Path@46..62
+              PathSegment@46..49
+                Ident@46..49 "std"
+              Colon2@49..51 "::"
+              PathSegment@51..54
+                Ident@51..54 "evm"
+              Colon2@54..56 "::"
+              PathSegment@56..62
+                Ident@56..62 "mstore"
+          CallArgList@62..83
+            LParen@62..63 "("
+            CallArg@63..72
+              Ident@63..69 "offset"
+              Colon@69..70 ":"
+              WhiteSpace@70..71 " "
+              LitExpr@71..72
+                Lit@71..72
+                  Int@71..72 "0"
+            Comma@72..73 ","
+            WhiteSpace@73..74 " "
+            CallArg@74..82
+              Ident@74..79 "value"
+              Colon@79..80 ":"
+              WhiteSpace@80..81 " "
+              PathExpr@81..82
+                Path@81..82
+                  PathSegment@81..82
+                    Ident@81..82 "a"
+            RParen@82..83 ")"
+      Newline@83..84 "\n"
+      WhiteSpace@84..88 "    "
+      ReturnStmt@88..94
+        ReturnKw@88..94 "return"
+      Newline@94..95 "\n"
+      RBrace@95..96 "}"
+  Newline@96..98 "\n\n"
+  UnsafeExpr@98..110
+    UnsafeKw@98..104 "unsafe"
+    WhiteSpace@104..105 " "
+    BinExpr@105..110
+      LitExpr@105..106
+        Lit@105..106
+          Int@105..106 "1"
+      WhiteSpace@106..107 " "
+      Plus@107..108 "+"
+      WhiteSpace@108..109 " "
+      LitExpr@109..110
+        Lit@109..110
+          Int@109..110 "1"
+  Newline@110..112 "\n\n"
+  UnsafeExpr@112..124
+    UnsafeKw@112..118 "unsafe"
+    WhiteSpace@118..119 " "
+    CallExpr@119..124
+      PathExpr@119..122
+        Path@119..122
+          PathSegment@119..122
+            Ident@119..122 "bar"
+      CallArgList@122..124
+        LParen@122..123 "("
+        RParen@123..124 ")"
+  Newline@124..125 "\n"
+

crates/parser2/test_files/syntax_node/stmts/let.fe

@@ -20,4 +20,6 @@ let x = if b {
 let x = match b {
     MyEnum::A(x) | MyEnum::B(x) => x
     _ => 0
-}
+}
+
+let x = unsafe bar()

crates/parser2/test_files/syntax_node/stmts/let.snap

@@ -3,7 +3,7 @@ source: crates/parser2/tests/syntax_node.rs
 expression: node
 input_file: crates/parser2/test_files/syntax_node/stmts/let.fe
 ---
-Root@0..231
+Root@0..253
   LetStmt@0..5
     LetKw@0..3 "let"
     WhiteSpace@3..4 " "
@@ -298,4 +298,26 @@ Root@0..231
               Int@228..229 "0"
         Newline@229..230 "\n"
         RBrace@230..231 "}"
+  Newline@231..233 "\n\n"
+  LetStmt@233..253
+    LetKw@233..236 "let"
+    WhiteSpace@236..237 " "
+    PathPat@237..238
+      Path@237..238
+        PathSegment@237..238
+          Ident@237..238 "x"
+    WhiteSpace@238..239 " "
+    Eq@239..240 "="
+    WhiteSpace@240..241 " "
+    UnsafeExpr@241..253
+      UnsafeKw@241..247 "unsafe"
+      WhiteSpace@247..248 " "
+      CallExpr@248..253
+        PathExpr@248..251
+          Path@248..251
+            PathSegment@248..251
+              Ident@248..251 "bar"
+        CallArgList@251..253
+          LParen@251..252 "("
+          RParen@252..253 ")"