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// Test assignment to const and function name bindings. The latter is kind of a
// const binding, but only throws in strict mode.
function notEvaluated() {
throw new Error("should not be evaluated");
}
// AndAssignExpr with const lexical binding.
{
const a = false;
a &&= notEvaluated();
assertEq(a, false);
const b = true;
assertThrowsInstanceOf(() => { b &&= 1; }, TypeError);
assertEq(b, true);
}
// AndAssignExpr with function name binding.
{
let f = function fn() {
fn &&= true;
assertEq(fn, f);
};
f();
let g = function fn() {
"use strict";
assertThrowsInstanceOf(() => { fn &&= 1; }, TypeError);
assertEq(fn, g);
};
g();
}
// OrAssignExpr with const lexical binding.
{
const a = true;
a ||= notEvaluated();
assertEq(a, true);
const b = false;
assertThrowsInstanceOf(() => { b ||= 0; }, TypeError);
assertEq(b, false);
}
// OrAssignExpr with function name binding.
{
let f = function fn() {
fn ||= notEvaluated();
assertEq(fn, f);
};
f();
let g = function fn() {
"use strict";
fn ||= notEvaluated();
assertEq(fn, g);
};
g();
}
// CoalesceAssignExpr with const lexical binding.
{
const a = true;
a ??= notEvaluated();
assertEq(a, true);
const b = null;
assertThrowsInstanceOf(() => { b ??= 0; }, TypeError);
assertEq(b, null);
}
// CoalesceAssignExpr with function name binding.
{
let f = function fn() {
fn ??= notEvaluated();
assertEq(fn, f);
};
f();
let g = function fn() {
"use strict";
fn ??= notEvaluated();
assertEq(fn, g);
};
g();
}
if (typeof reportCompare === "function")
reportCompare(0, 0);