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var BUGNUMBER = 1185106;
var summary = "async arrow function syntax";
print(BUGNUMBER + ": " + summary);
if (typeof Reflect !== "undefined" && Reflect.parse) {
// Parameters.
Reflect.parse("async () => 1");
Reflect.parse("async a => 1");
Reflect.parse("async (a) => 1");
Reflect.parse("async async => 1");
Reflect.parse("async (async) => 1");
Reflect.parse("async ([a]) => 1");
Reflect.parse("async ([a, b]) => 1");
Reflect.parse("async ({a}) => 1");
Reflect.parse("async ({a, b}) => 1");
assertThrowsInstanceOf(() => Reflect.parse("async await => 1"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("async (await) => 1"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("async ([await]) => 1"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("async ({await}) => 1"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("async (a=await) => 1"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("async ([a=await]) => 1"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("async ({a=await}) => 1"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("async (a=await 1) => 1"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("async ([a=await 1]) => 1"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("async ({a=await 1}) => 1"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("async [a] => 1"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("async [a, b] => 1"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("async {a} => 1"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("async {a: b} => 1"), SyntaxError);
// Expression body.
Reflect.parse("async a => a == b");
// Expression body with nested async function.
Reflect.parse("async a => async");
Reflect.parse("async a => async b => c");
Reflect.parse("async a => async function() {}");
Reflect.parse("async a => async function b() {}");
assertThrowsInstanceOf(() => Reflect.parse("async a => async b"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("async a => async function"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("async a => async function()"), SyntaxError);
// Expression body with `await`.
Reflect.parse("async a => await 1");
Reflect.parse("async a => await await 1");
Reflect.parse("async a => await await await 1");
assertThrowsInstanceOf(() => Reflect.parse("async a => await"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("async a => await await"), SyntaxError);
// `await` is Unary Expression and it cannot have `async` function as an
// operand.
assertThrowsInstanceOf(() => Reflect.parse("async a => await async X => Y"), SyntaxError);
Reflect.parse("async a => await (async X => Y)");
// But it can have `async` identifier as an operand.
Reflect.parse("async async => await async");
// Block body.
Reflect.parse("async X => {yield}");
// `yield` handling.
Reflect.parse("async X => yield");
Reflect.parse("async yield => X");
Reflect.parse("async yield => yield");
Reflect.parse("async X => {yield}");
Reflect.parse("async X => {yield}");
Reflect.parse("async yield => {X}");
Reflect.parse("async yield => {yield}");
Reflect.parse("function* g() { async X => yield }");
assertThrowsInstanceOf(() => Reflect.parse("'use strict'; async yield => X"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("'use strict'; async (yield) => X"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("'use strict'; async X => yield"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("'use strict'; async X => {yield}"), SyntaxError);
assertThrows(() => Reflect.parse("function* g() { async yield => X }"));
assertThrows(() => Reflect.parse("function* g() { async (yield) => X }"));
assertThrows(() => Reflect.parse("function* g() { async ([yield]) => X }"));
assertThrows(() => Reflect.parse("function* g() { async ({yield}) => X }"));
// Not async functions.
Reflect.parse("async ()");
Reflect.parse("async (a)");
Reflect.parse("async (async)");
Reflect.parse("async ([a])");
Reflect.parse("async ([a, b])");
Reflect.parse("async ({a})");
Reflect.parse("async ({a, b})");
// Async arrow function is assignment expression.
Reflect.parse("a ? async () => {1} : b");
Reflect.parse("a ? b : async () => {1}");
assertThrowsInstanceOf(() => Reflect.parse("async () => {1} ? a : b"), SyntaxError);
}
if (typeof reportCompare === "function")
reportCompare(true, true);