Parse static async private methods in classes (#2315)

This Pull Request changes the following:

- Adjust `AsyncMethod` parsing to parse private identifiers.

boa_engine/src/syntax/parser/expression/primary/object_initializer/mod.rs

@@ -215,9 +215,20 @@ where
                         property_name,
                     ));
                 }
-                let (property_name, method) =
+                let (class_element_name, method) =
                     AsyncMethod::new(self.allow_yield, self.allow_await).parse(cursor, interner)?;
 
+                let property_name = if let object::ClassElementName::PropertyName(property_name) =
+                    class_element_name
+                {
+                    property_name
+                } else {
+                    return Err(ParseError::general(
+                        "private identifiers not allowed in object literal",
+                        position,
+                    ));
+                };
+
                 // It is a Syntax Error if HasDirectSuper of MethodDefinition is true.
                 if has_direct_super(method.body(), method.parameters()) {
                     return Err(ParseError::general("invalid super usage", position));
@@ -888,7 +899,7 @@ impl<R> TokenParser<R> for AsyncMethod
 where
     R: Read,
 {
-    type Output = (object::PropertyName, MethodDefinition);
+    type Output = (object::ClassElementName, MethodDefinition);
 
     fn parse(
         self,
@@ -897,8 +908,8 @@ where
     ) -> Result<Self::Output, ParseError> {
         let _timer = Profiler::global().start_event("AsyncMethod", "Parsing");
 
-        let property_name =
-            PropertyName::new(self.allow_yield, self.allow_await).parse(cursor, interner)?;
+        let class_element_name =
+            ClassElementName::new(self.allow_yield, self.allow_await).parse(cursor, interner)?;
 
         let params = UniqueFormalParameters::new(false, true).parse(cursor, interner)?;
 
@@ -941,7 +952,7 @@ where
         }
 
         Ok((
-            property_name,
+            class_element_name,
             MethodDefinition::Async(AsyncFunctionExpr::new(None, params, body)),
         ))
     }

boa_engine/src/syntax/parser/statement/declaration/hoistable/class_decl/mod.rs

@@ -793,23 +793,37 @@ where
                         let name_position = token.span().start();
                         let strict = cursor.strict_mode();
                         cursor.set_strict_mode(true);
-                        let (property_name, method) =
+                        let (class_element_name, method) =
                             AsyncMethod::new(self.allow_yield, self.allow_await)
                                 .parse(cursor, interner)?;
                         cursor.set_strict_mode(strict);
-                        if r#static {
-                            if let Some(name) = property_name.prop_name() {
-                                if name == Sym::PROTOTYPE {
+
+                        match class_element_name {
+                            ClassElementName::PropertyName(property_name) if r#static => {
+                                if let Some(Sym::PROTOTYPE) = property_name.prop_name() {
                                     return Err(ParseError::general(
                                             "class may not have static method definitions named 'prototype'",
                                             name_position,
                                         ));
                                 }
-                            }
                                 ClassElementNode::StaticMethodDefinition(property_name, method)
-                        } else {
+                            }
+                            ClassElementName::PropertyName(property_name) => {
                                 ClassElementNode::MethodDefinition(property_name, method)
                             }
+                            ClassElementName::PrivateIdentifier(Sym::CONSTRUCTOR) if r#static => {
+                                return Err(ParseError::general(
+                                    "class constructor may not be a private method",
+                                    name_position,
+                                ))
+                            }
+                            ClassElementName::PrivateIdentifier(identifier) if r#static => {
+                                ClassElementNode::PrivateStaticMethodDefinition(identifier, method)
+                            }
+                            ClassElementName::PrivateIdentifier(identifier) => {
+                                ClassElementNode::PrivateMethodDefinition(identifier, method)
+                            }
+                        }
                     }
                 }
             }