support optional dynamic property access

y21 · Dec 25, 2024 · d848f71 · d848f71
1 parent 49a3cb4
commit d848f71
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Showing 5 changed files with 30 additions and 4 deletions.
diff --git a/crates/dash_compiler/src/lib.rs b/crates/dash_compiler/src/lib.rs
@@ -1546,6 +1546,10 @@ impl Visitor<Result<(), Error>> for FunctionCompiler<'_> {
                     ib.build_static_prop_access(ident, false)
                         .map_err(|_| Error::ConstantPoolLimitExceeded(span))?;
                 }
+                OptionalChainingComponent::Dyn(expr) => {
+                    ib.accept_expr(expr)?;
+                    ib.build_dynamic_prop_access(false);
+                }
             }
         }
         ib.build_jmp(Label::IfEnd, true);

diff --git a/crates/dash_lexer/src/lib.rs b/crates/dash_lexer/src/lib.rs
@@ -574,7 +574,7 @@ impl<'a, 'interner> Lexer<'a, 'interner> {
             b'~' => self.token(TokenType::BitwiseNot),
             b'?' => self.conditional_token(TokenType::Conditional, &[
                 ("?=", TokenType::LogicalNullishAssignment),
-                (".[", TokenType::OptionalBracket),
+                (".[", TokenType::OptionalSquareBrace),
                 (".(", TokenType::OptionalCall),
                 ("?", TokenType::NullishCoalescing),
                 (".", TokenType::OptionalDot),

diff --git a/crates/dash_middle/src/lexer/token.rs b/crates/dash_middle/src/lexer/token.rs
@@ -281,7 +281,7 @@ pub enum TokenType {
     OptionalDot,
 
     #[display(fmt = "?.[")]
-    OptionalBracket,
+    OptionalSquareBrace,
 
     #[display(fmt = "?.(")]
     OptionalCall,

diff --git a/crates/dash_middle/src/parser/expr.rs b/crates/dash_middle/src/parser/expr.rs
@@ -77,6 +77,7 @@ impl fmt::Display for OptionalChainingExpression {
         for component in &self.components {
             match component {
                 OptionalChainingComponent::Ident(symbol) => write!(f, ".{symbol}")?,
+                OptionalChainingComponent::Dyn(expr) => write!(f, "[{expr}]")?,
             }
         }
         Ok(())
@@ -85,7 +86,10 @@ impl fmt::Display for OptionalChainingExpression {
 
 #[derive(Debug, Clone)]
 pub enum OptionalChainingComponent {
+    /// ?.x
     Ident(Symbol),
+    /// ?.[expr]
+    Dyn(Expr),
 }
 
 #[derive(Debug, Clone, Display)]

diff --git a/crates/dash_parser/src/expr.rs b/crates/dash_parser/src/expr.rs
@@ -338,6 +338,7 @@ impl Parser<'_, '_> {
                     TokenType::Dot,
                     TokenType::LeftSquareBrace,
                     TokenType::OptionalDot,
+                    TokenType::OptionalSquareBrace,
                 ]),
                 false,
             )
@@ -411,9 +412,26 @@ impl Parser<'_, '_> {
                 TokenType::LeftSquareBrace => {
                     let property = self.parse_expression()?;
                     self.eat(TokenType::RightSquareBrace, true)?;
+                    if let ExprKind::Chaining(c) = &mut expr.kind {
+                        c.components.push(OptionalChainingComponent::Dyn(property));
+                        expr.span = expr.span.to(self.previous()?.span);
+                    } else {
+                        expr = Expr {
+                            span: expr.span.to(self.previous()?.span),
+                            kind: ExprKind::property_access(true, expr, property),
+                        };
+                    }
+                }
+                TokenType::OptionalSquareBrace => {
+                    let property = self.parse_expression()?;
+                    self.eat(TokenType::RightSquareBrace, true)?;
+                    let span = expr.span.to(self.previous()?.span);
                     expr = Expr {
-                        span: expr.span.to(property.span),
-                        kind: ExprKind::property_access(true, expr, property),
+                        span,
+                        kind: ExprKind::Chaining(OptionalChainingExpression {
+                            base: Box::new(expr),
+                            components: vec![OptionalChainingComponent::Dyn(property)],
+                        }),
                     };
                 }
                 _ => unreachable!(),