[Merged by Bors] - Extract the ast to a crate

Cargo.toml

@@ -2,6 +2,7 @@
 members = [
     "boa_cli",
     "boa_engine",
+    "boa_ast",
     "boa_gc",
     "boa_interner",
     "boa_profiler",
@@ -28,6 +29,7 @@ boa_gc = { version = "0.16.0", path = "boa_gc" }
 boa_profiler = { version = "0.16.0", path = "boa_profiler" }
 boa_unicode = { version = "0.16.0", path = "boa_unicode" }
 boa_macros = { version = "0.16.0", path = "boa_macros" }
+boa_ast = { version = "0.16.0", path = "boa_ast" }
 
 [workspace.metadata.workspaces]
 allow_branch = "main"

boa_ast/Cargo.toml

@@ -0,0 +1,22 @@
+[package]
+name = "boa_ast"
+description = "Abstract Syntax Tree definition for the Boa JavaScript engine."
+keywords = ["javascript", "js", "syntax", "ast"]
+categories = ["parser-implementations", "compilers"]
+version.workspace = true
+edition.workspace = true
+authors.workspace = true
+license.workspace = true
+repository.workspace = true
+rust-version.workspace = true
+
+[features]
+serde = ["boa_interner/serde", "dep:serde"]
+
+[dependencies]
+boa_interner.workspace = true
+boa_macros.workspace = true
+rustc-hash = "1.1.0"
+serde = { version = "1.0.147", features = ["derive"], optional = true }
+bitflags = "1.3.2"
+num-bigint = "0.4.3"

boa_engine/src/syntax/ast/declaration/mod.rs → boa_ast/src/declaration/mod.rs

@@ -21,17 +21,16 @@ use super::{
 };
 use boa_interner::{Interner, ToIndentedString, ToInternedString};
 use core::ops::ControlFlow;
-use tap::Tap;
 
 mod variable;
 
-use crate::syntax::ast::visitor::{VisitWith, Visitor, VisitorMut};
+use crate::visitor::{VisitWith, Visitor, VisitorMut};
 pub use variable::*;
 
 /// The `Declaration` Parse Node.
 ///
 /// See the [module level documentation][self] for more information.
-#[cfg_attr(feature = "deser", derive(serde::Serialize, serde::Deserialize))]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 #[derive(Clone, Debug, PartialEq)]
 pub enum Declaration {
     /// See [`Function`]
@@ -163,7 +162,11 @@ impl ToIndentedString for Declaration {
             Declaration::AsyncFunction(af) => af.to_indented_string(interner, indentation),
             Declaration::AsyncGenerator(ag) => ag.to_indented_string(interner, indentation),
             Declaration::Class(c) => c.to_indented_string(interner, indentation),
-            Declaration::Lexical(l) => l.to_interned_string(interner).tap_mut(|s| s.push(';')),
+            Declaration::Lexical(l) => {
+                let mut s = l.to_interned_string(interner);
+                s.push(';');
+                s
+            }
         }
     }
 }

boa_engine/src/syntax/ast/declaration/variable.rs → boa_ast/src/declaration/variable.rs

@@ -3,14 +3,14 @@
 use core::ops::ControlFlow;
 use std::convert::TryFrom;
 
-use crate::syntax::ast::visitor::{VisitWith, Visitor, VisitorMut};
-use crate::syntax::ast::{
+use crate::try_break;
+use crate::visitor::{VisitWith, Visitor, VisitorMut};
+use crate::{
     expression::{Expression, Identifier},
     join_nodes,
     pattern::Pattern,
     ContainsSymbol, Statement,
 };
-use crate::try_break;
 use boa_interner::{Interner, ToInternedString};
 
 use super::Declaration;
@@ -44,7 +44,7 @@ use super::Declaration;
 /// [var]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/var
 /// [varstmt]: https://tc39.es/ecma262/#prod-VariableStatement
 /// [hoisting]: https://developer.mozilla.org/en-US/docs/Glossary/Hoisting
-#[cfg_attr(feature = "deser", derive(serde::Serialize, serde::Deserialize))]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 #[derive(Clone, Debug, PartialEq)]
 pub struct VarDeclaration(pub VariableList);
 
@@ -91,7 +91,7 @@ impl VisitWith for VarDeclaration {
 /// the variable declaration.
 ///
 /// [lexical declaration]: https://tc39.es/ecma262/#sec-let-and-const-declarations
-#[cfg_attr(feature = "deser", derive(serde::Serialize, serde::Deserialize))]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 #[derive(Clone, Debug, PartialEq)]
 pub enum LexicalDeclaration {
     /// A <code>[const]</code> variable creates a constant whose scope can be either global or local
@@ -118,6 +118,7 @@ pub enum LexicalDeclaration {
 
 impl LexicalDeclaration {
     /// Gets the inner variable list of the `LexicalDeclaration`
+    #[must_use]
     pub fn variable_list(&self) -> &VariableList {
         match self {
             LexicalDeclaration::Const(list) | LexicalDeclaration::Let(list) => list,
@@ -185,14 +186,15 @@ impl VisitWith for LexicalDeclaration {
 }
 
 /// List of variables in a variable declaration.
-#[cfg_attr(feature = "deser", derive(serde::Serialize, serde::Deserialize))]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 #[derive(Clone, Debug, PartialEq)]
 pub struct VariableList {
     list: Box<[Variable]>,
 }
 
 impl VariableList {
     /// Creates a variable list if the provided list of [`Variable`] is not empty.
+    #[must_use]
     pub fn new(list: Box<[Variable]>) -> Option<Self> {
         if list.is_empty() {
             return None;
@@ -274,7 +276,7 @@ impl TryFrom<Vec<Variable>> for VariableList {
 /// [spec1]: https://tc39.es/ecma262/#prod-LexicalBinding
 /// [spec2]: https://tc39.es/ecma262/#prod-VariableDeclaration
 /// [spec3]:  https://tc39.es/ecma262/#sec-declarations-and-the-variable-statement
-#[cfg_attr(feature = "deser", derive(serde::Serialize, serde::Deserialize))]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 #[derive(Clone, Debug, PartialEq)]
 pub struct Variable {
     binding: Binding,
@@ -295,7 +297,8 @@ impl ToInternedString for Variable {
 impl Variable {
     /// Creates a new variable declaration from a `BindingIdentifier`.
     #[inline]
-    pub(in crate::syntax) fn from_identifier(ident: Identifier, init: Option<Expression>) -> Self {
+    #[must_use]
+    pub fn from_identifier(ident: Identifier, init: Option<Expression>) -> Self {
         Self {
             binding: Binding::Identifier(ident),
             init,
@@ -304,23 +307,32 @@ impl Variable {
 
     /// Creates a new variable declaration from a `Pattern`.
     #[inline]
-    pub(in crate::syntax) fn from_pattern(pattern: Pattern, init: Option<Expression>) -> Self {
+    #[must_use]
+    pub fn from_pattern(pattern: Pattern, init: Option<Expression>) -> Self {
         Self {
             binding: Binding::Pattern(pattern),
             init,
         }
     }
     /// Gets the variable declaration binding.
-    pub(crate) fn binding(&self) -> &Binding {
+    #[must_use]
+    pub fn binding(&self) -> &Binding {
         &self.binding
     }
 
     /// Gets the initialization expression for the variable declaration, if any.
     #[inline]
-    pub(crate) fn init(&self) -> Option<&Expression> {
+    #[must_use]
+    pub fn init(&self) -> Option<&Expression> {
         self.init.as_ref()
     }
 
+    /// Gets the list of declared identifiers.
+    #[must_use]
+    pub fn idents(&self) -> Vec<Identifier> {
+        self.binding.idents()
+    }
+
     #[inline]
     pub(crate) fn contains_arguments(&self) -> bool {
         if let Some(ref node) = self.init {
@@ -338,19 +350,15 @@ impl Variable {
     ///
     /// [spec]: https://tc39.es/ecma262/#sec-static-semantics-contains
     #[inline]
-    pub(crate) fn contains(&self, symbol: ContainsSymbol) -> bool {
+    #[must_use]
+    pub fn contains(&self, symbol: ContainsSymbol) -> bool {
         if let Some(ref node) = self.init {
             if node.contains(symbol) {
                 return true;
             }
         }
         self.binding.contains(symbol)
     }
-
-    /// Gets the list of declared identifiers.
-    pub(crate) fn idents(&self) -> Vec<Identifier> {
-        self.binding.idents()
-    }
 }
 
 impl VisitWith for Variable {
@@ -383,7 +391,7 @@ impl VisitWith for Variable {
 ///  - [ECMAScript reference: 14.3 Declarations and the Variable Statement][spec]
 ///
 /// [spec]:  https://tc39.es/ecma262/#sec-declarations-and-the-variable-statement
-#[cfg_attr(feature = "deser", derive(serde::Serialize, serde::Deserialize))]
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 #[derive(Clone, Debug, PartialEq)]
 pub enum Binding {
     /// A single identifier binding.
@@ -458,47 +466,3 @@ impl VisitWith for Binding {
         }
     }
 }
-
-#[cfg(test)]
-mod tests {
-    #[test]
-    fn fmt_binding_pattern() {
-        crate::syntax::ast::test_formatting(
-            r#"
-        var { } = {
-            o: "1",
-        };
-        var { o_v1 } = {
-            o_v1: "1",
-        };
-        var { o_v2 = "1" } = {
-            o_v2: "2",
-        };
-        var { a : o_v3 = "1" } = {
-            a: "2",
-        };
-        var { ... o_rest_v1 } = {
-            a: "2",
-        };
-        var { o_v4, o_v5, o_v6 = "1", a : o_v7 = "1", ... o_rest_v2 } = {
-            o_v4: "1",
-            o_v5: "1",
-        };
-        var [] = [];
-        var [ , ] = [];
-        var [ a_v1 ] = [1, 2, 3];
-        var [ a_v2, a_v3 ] = [1, 2, 3];
-        var [ a_v2, , a_v3 ] = [1, 2, 3];
-        var [ ... a_rest_v1 ] = [1, 2, 3];
-        var [ a_v4, , ... a_rest_v2 ] = [1, 2, 3];
-        var [ { a_v5 } ] = [{
-            a_v5: 1,
-        }, {
-            a_v5: 2,
-        }, {
-            a_v5: 3,
-        }];
-        "#,
-        );
-    }
-}