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// Verify bytecode emitter accepts all valid optional chain first expressions.
const expressions = [
"this",
"ident",
"null",
"true",
"false",
"123",
"123n",
"'str'",
"[]",
"{}",
"function(){}",
"class{}",
"function*(){}",
"async function(){}",
"async function*(){}",
"/a/",
"`str`",
"(a + b)",
"a[b]",
"a.b",
"a``",
"super[a]",
"super.a",
"new.target",
"import.meta",
"new C()",
"new C",
"f()",
"super()",
"a?.b",
"a?.[b]",
"a?.()",
"a?.``",
];
function tryParse(s, f = Function) {
try { f(s); } catch {}
}
function tryRun(s, f = Function) {
try { f(s)(); } catch {}
}
for (let expr of expressions) {
// Evaluate in an expression context.
tryRun(`void (${expr}?.());`);
tryRun(`void (${expr}?.p());`);
// Also try parenthesized.
tryRun(`void ((${expr})?.());`);
tryRun(`void ((${expr})?.p());`);
}
function inClassConstructor(s) {
return `class C { constructor() { ${s} } }`;
}
for (let expr of ["super[a]", "super.a", "super()"]) {
// Evaluate in an expression context.
tryRun(inClassConstructor(`void (${expr}?.());`));
tryRun(inClassConstructor(`void (${expr}?.p());`));
// Also try parenthesized.
tryRun(inClassConstructor(`void ((${expr})?.());`));
tryRun(inClassConstructor(`void ((${expr})?.p());`));
}
if (typeof parseModule === "function") {
const expressions = [
"import.meta",
"import('')",
];
for (let expr of expressions) {
// Evaluate in an expression context.
tryParse(`void (${expr}?.());`, parseModule);
tryParse(`void (${expr}?.p());`, parseModule);
// Also try parenthesized.
tryParse(`void ((${expr})?.());`, parseModule);
tryParse(`void ((${expr})?.p());`, parseModule);
}
}
if (typeof reportCompare === "function")
reportCompare(true, true);