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// Named class definitions should create an immutable inner binding.
// Since all code in classes is in strict mode, attempts to mutate it
// should throw.
class Foof { constructor() { }; tryBreak() { Foof = 4; } }
for (let result of [Foof, class Bar { constructor() { }; tryBreak() { Bar = 4; } }])
assertThrowsInstanceOf(() => new result().tryBreak(), TypeError);
{
class foo { constructor() { }; tryBreak() { foo = 4; } }
for (let result of [foo, class Bar { constructor() { }; tryBreak() { Bar = 4 } }])
assertThrowsInstanceOf(() => new result().tryBreak(), TypeError);
}
// TDZ applies to inner bindings
assertThrowsInstanceOf(()=>eval(`class Bar {
constructor() { };
[Bar] () { };
}`), ReferenceError);
assertThrowsInstanceOf(()=>eval(`(class Bar {
constructor() { };
[Bar] () { };
})`), ReferenceError);
// There's no magic "inner binding" global
{
class Foo {
constructor() { };
test() {
class Bar {
constructor() { }
test() { return Foo === Bar }
}
return new Bar().test();
}
}
assertEq(new Foo().test(), false);
assertEq(new class foo {
constructor() { };
test() {
return new class bar {
constructor() { }
test() { return foo === bar }
}().test();
}
}().test(), false);
}
// Inner bindings are shadowable
{
class Foo {
constructor() { }
test(Foo) { return Foo; }
}
assertEq(new Foo().test(4), 4);
assertEq(new class foo {
constructor() { };
test(foo) { return foo }
}().test(4), 4);
}
// Inner bindings in expressions should shadow even existing names.
class Foo { constructor() { } static method() { throw new Error("NO!"); } }
assertEq(new class Foo {
constructor() { };
static method() { return 4; };
test() { return Foo.method(); }
}().test(), 4);
// The outer binding is distinct from the inner one
{
let orig_X;
class X {
constructor() { }
f() { assertEq(X, orig_X); }
}
orig_X = X;
X = 13;
assertEq(X, 13);
new orig_X().f();
}
if (typeof reportCompare === "function")
reportCompare(0, 0, "OK");