fix(codegen): missing parenthesis for PrivateInExpression (#4865)

crates/oxc_codegen/src/gen.rs

@@ -1054,7 +1054,7 @@ impl<'a, const MINIFY: bool> GenExpr<MINIFY> for Expression<'a> {
             Self::UpdateExpression(expr) => expr.gen_expr(p, precedence, ctx),
             Self::UnaryExpression(expr) => expr.gen_expr(p, precedence, ctx),
             Self::BinaryExpression(expr) => expr.gen_expr(p, precedence, ctx),
-            Self::PrivateInExpression(expr) => expr.gen(p, ctx),
+            Self::PrivateInExpression(expr) => expr.gen_expr(p, precedence, ctx),
             Self::LogicalExpression(expr) => expr.gen_expr(p, precedence, ctx),
             Self::ConditionalExpression(expr) => expr.gen_expr(p, precedence, ctx),
             Self::AssignmentExpression(expr) => expr.gen_expr(p, precedence, ctx),
@@ -1778,11 +1778,13 @@ impl<const MINIFY: bool> Gen<MINIFY> for BinaryOperator {
     }
 }
 
-impl<'a, const MINIFY: bool> Gen<MINIFY> for PrivateInExpression<'a> {
-    fn gen(&self, p: &mut Codegen<{ MINIFY }>, ctx: Context) {
-        self.left.gen(p, ctx);
-        p.print_str(" in ");
-        self.right.gen_expr(p, Precedence::Shift, Context::empty());
+impl<'a, const MINIFY: bool> GenExpr<MINIFY> for PrivateInExpression<'a> {
+    fn gen_expr(&self, p: &mut Codegen<{ MINIFY }>, precedence: Precedence, ctx: Context) {
+        p.wrap(precedence >= Precedence::Compare, |p| {
+            self.left.gen(p, ctx);
+            p.print_str(" in ");
+            self.right.gen_expr(p, Precedence::Equals, Context::empty());
+        });
     }
 }
 

crates/oxc_codegen/tests/integration/unit.rs

@@ -9,8 +9,14 @@ fn module_decl() {
 }
 
 #[test]
-fn new_expr() {
+fn expr() {
     test("new (foo()).bar();", "new (foo()).bar();\n");
+    test(
+        "class Foo { #test
+          bar() { if (!(#test in Foo)) { } }
+        }",
+        "class Foo {\n\t#test;\n\tbar() {\n\t\tif (!(#test in Foo)) {}\n\t}\n}\n",
+    );
 }
 
 #[test]