//@ if isFTLEnabled then runFTLNoCJIT else skip end function shouldBe(actual, expected) { if (actual !== expected) throw new Error('bad value: ' + actual); } var didFTLCompile = false; var ftlTrue = $vm.ftlTrue; function test1(array) { didFTLCompile = ftlTrue(); return 2 in array; } noInline(test1); var object = { a: 10 }; Object.defineProperties(object, { "0": { get: function() { return this.a; }, set: function(x) { this.a = x; }, }, }); var array = [1, 2, 3, 4]; array.__proto__ = object; ensureArrayStorage(array); didFTLCompile = false; for (var i = 0; i < 1e5; ++i) shouldBe(test1(array), true); shouldBe(didFTLCompile, true); var array = [1, 2, , 4]; array.__proto__ = object; ensureArrayStorage(array); shouldBe(test1(array), false); var array = []; array.__proto__ = object; ensureArrayStorage(array); shouldBe(test1(array), false); function test2(array) { didFTLCompile = ftlTrue(); return 9 in array; } noInline(test2); var array1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]; array1.__proto__ = object; ensureArrayStorage(array1); var array2 = [1, 2]; array2.__proto__ = object; ensureArrayStorage(array2); didFTLCompile = false; for (var i = 0; i < 1e5; ++i) shouldBe(test2(array2), false); shouldBe(didFTLCompile, true); shouldBe(test2(array2), false); shouldBe(test2(array1), true);