Added some async function expr parsing tests

boa/src/syntax/parser/expression/primary/async_function_expression/mod.rs

@@ -6,6 +6,10 @@
 //!
 //! [mdn]:
 //! [spec]:
+
+#[cfg(test)]
+mod tests;
+
 use crate::{
     syntax::{
         ast::{node::AsyncFunctionExpr, Keyword, Punctuator},

boa/src/syntax/parser/expression/primary/async_function_expression/tests.rs

@@ -0,0 +1,66 @@
+use crate::syntax::{
+    ast::{
+        node::{AsyncFunctionExpr, ConstDecl, ConstDeclList, Return, StatementList},
+        Const,
+    },
+    parser::tests::check_parser,
+};
+
+/// Checks async expression parsing.
+#[test]
+fn check_async_expression() {
+    check_parser(
+        "const add = async function() {
+            return 1; 
+        };
+        ",
+        vec![ConstDeclList::from(vec![ConstDecl::new(
+            "add",
+            Some(
+                AsyncFunctionExpr::new::<Option<Box<str>>, _, StatementList>(
+                    None,
+                    [],
+                    vec![Return::new::<_, _, Option<Box<str>>>(Const::from(1), None).into()].into(),
+                ),
+            ),
+        )])
+        .into()],
+    );
+}
+
+/// Checks async expression parsing.
+#[test]
+fn check_nested_async_expression() {
+    check_parser(
+        "const a = async function() {
+            const b = async function() {
+                return 1; 
+            };
+        };
+        ",
+        vec![ConstDeclList::from(vec![ConstDecl::new(
+            "a",
+            Some(
+                AsyncFunctionExpr::new::<Option<Box<str>>, _, StatementList>(
+                    None,
+                    [],
+                    vec![ConstDeclList::from(vec![ConstDecl::new(
+                        "b",
+                        Some(
+                            AsyncFunctionExpr::new::<Option<Box<str>>, _, StatementList>(
+                                None,
+                                [],
+                                vec![Return::new::<_, _, Option<Box<str>>>(Const::from(1), None)
+                                    .into()]
+                                .into(),
+                            ),
+                        ),
+                    )])
+                    .into()]
+                    .into(),
+                ),
+            ),
+        )])
+        .into()],
+    );
+}