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var BUGNUMBER = 1185106;
var summary = "async/await syntax";
print(BUGNUMBER + ": " + summary);
if (typeof Reflect !== "undefined" && Reflect.parse) {
assertEq(Reflect.parse("function a() {}").body[0].async, false);
assertEq(Reflect.parse("function* a() {}").body[0].async, false);
assertEq(Reflect.parse("async function a() {}").body[0].async, true);
assertEq(Reflect.parse("() => {}").body[0].async, undefined);
// No line terminator after async
assertEq(Reflect.parse("async\nfunction a(){}").body[0].expression.name, "async");
// Async function expressions
assertEq(Reflect.parse("(async function() {})()").body[0].expression.callee.async, true);
assertEq(Reflect.parse("var k = async function() {}").body[0].declarations[0].init.async, true);
assertEq(Reflect.parse("var nmd = async function named() {}").body[0].declarations[0].init.id.name, "named");
// `await` handling for function declaration name inherits.
assertEq(Reflect.parse("async function await() {}").body[0].id.name, "await");
assertThrowsInstanceOf(() => Reflect.parse("async function f() { async function await() {} }"), SyntaxError);
// `await` is not allowed in function expression name.
assertThrowsInstanceOf(() => Reflect.parse("(async function await() {})"), SyntaxError);
// Awaiting not directly inside an async function is not allowed
assertThrowsInstanceOf(() => Reflect.parse("await 4;"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("function a() { await 4; }"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("function* a() { await 4; }"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("async function k() { function a() { await 4; } }"), SyntaxError);
// Await is not allowed as a default expr.
assertThrowsInstanceOf(() => Reflect.parse("async function a(k = await 3) {}"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("async function a() { async function b(k = await 3) {} }"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("async function a() { async function b(k = [await 3]) {} }"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("async function a() { async function b([k = await 3]) {} }"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("async function a() { async function b([k = [await 3]]) {} }"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("async function a() { async function b({k = await 3}) {} }"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("async function a() { async function b({k = [await 3]}) {} }"), SyntaxError);
// Await is not legal as an identifier in an async function.
assertThrowsInstanceOf(() => Reflect.parse("async function a() { var await = 4; }"), SyntaxError);
assertThrowsInstanceOf(() => Reflect.parse("async function a() { return await; }"), SyntaxError);
// Await is still available as an identifier name in strict mode code.
Reflect.parse("function a() { 'use strict'; var await = 3; }");
Reflect.parse("'use strict'; var await = 3;");
// Await is treated differently depending on context. Various cases.
Reflect.parse("var await = 3; async function a() { await 4; }");
Reflect.parse("async function a() { await 4; } var await = 5");
Reflect.parse("async function a() { function b() { return await; } }");
Reflect.parse("async function a() { var k = { async: 4 } }");
Reflect.parse("function a() { await: 4 }");
assertEq(Reflect.parse("async function a() { await 4; }")
.body[0].body.body[0].expression.operator, "await");
assertEq(Reflect.parse("async function a() { async function b() { await 4; } }")
.body[0].body.body[0].body.body[0].expression.operator, "await");
// operator priority test
assertEq(Reflect.parse("async function a() { await 2 + 3; }")
.body[0].body.body[0].expression.left.argument.value, 2);
assertEq(Reflect.parse("async function a() { await 2 + 3; }")
.body[0].body.body[0].expression.left.operator, "await");
assertEq(Reflect.parse("async function a() { await 2 + 3; }")
.body[0].body.body[0].expression.right.value, 3);
// blocks and other constructions
assertEq(Reflect.parse("{ async function a() { return 2; } }")
.body[0].body[0].async, true);
// Async function expression is primary expression.
Reflect.parse("(async function a() {}.constructor)");
}
if (typeof reportCompare === "function")
reportCompare(true, true);