LibJS: Allow parenthesized dynamic import under new

Parenthesized import calls are valid callees for new expressions. The
unparenthesized form remains a syntax error, but the grouped expression
must parse and then fail at runtime if the produced Promise is not a
constructor.

Add syntax coverage for both forms.

Libraries/LibJS/Rust/src/parser/expressions.rs

@@ -1189,6 +1189,7 @@ impl Parser<'_> {
             return self.expression(start, ExpressionKind::MetaProperty(MetaPropertyType::NewTarget));
         }
 
+        let callee_starts_with_grouping_paren = self.match_token(TokenType::ParenOpen);
         let callee = if self.match_token(TokenType::New) {
             self.parse_new_expression()
         } else {
@@ -1196,7 +1197,7 @@ impl Parser<'_> {
             self.parse_expression(PRECEDENCE_MEMBER, Associativity::Right, forbidden)
         };
 
-        if matches!(callee.inner, ExpressionKind::ImportCall(_)) {
+        if matches!(callee.inner, ExpressionKind::ImportCall(_)) && !callee_starts_with_grouping_paren {
             self.syntax_error("Cannot call new on dynamic import");
         }
 

Tests/LibJS/Runtime/syntax/dynamic-import-usage.js

@@ -5,6 +5,11 @@ describe("parsing", () => {
         expect("import('a', {options: true})").toEval();
     });
 
+    test("parenthesized import call can be used as a new callee", () => {
+        expect("new import('a')").not.toEval();
+        expect("new (import('a'), function() {})").toEval();
+    });
+
     test("does not crash on unexpected tokens after import", () => {
         expect("f = import('a')").toEval();