load(libdir + "asserts.js"); load(libdir + "eqArrayHelper.js"); load(libdir + "iteration.js"); function checkCommon(f) { assertEqArray(f.apply(null, ...[[1, 2, 3]]), [1, 2, 3]); assertEqArray(f.apply(...[null], [1, 2, 3]), [1, 2, 3]); assertEqArray(f.apply(...[null], ...[[1, 2, 3]]), [1, 2, 3]); assertEqArray(f.apply(...[null, [1, 2, 3]]), [1, 2, 3]); // other iterable objects assertEqArray(f.apply(...new Set([null, [1, 2, 3]])), [1, 2, 3]); assertEqArray(f.apply(...[null, [1, 2, 3]][Symbol.iterator]()), [1, 2, 3]); let itr = {}; itr[Symbol.iterator] = function() { return { i: 0, next: function() { this.i++; if (this.i == 1) return { value: null, done: false }; else if (this.i == 2) return { value: [1, 2, 3], done: false }; else return { value: undefined, done: true }; } }; }; assertEqArray(f.apply(...itr), [1, 2, 3]); function* gen() { yield null; yield [1, 2, 3]; } assertEqArray(f.apply(...gen()), [1, 2, 3]); let a; assertEqArray(f.apply(null, ...a=[[1, 2, 3]]), [1, 2, 3]); // 12.2.4.1.2 Runtime Semantics: ArrayAccumulation // If Type(spreadObj) is not Object, then throw a TypeError exception. assertThrowsInstanceOf(() => f.apply(null, ...null, [1, 2, 3]), TypeError); assertThrowsInstanceOf(() => f.apply(null, ...undefined, [1, 2, 3]), TypeError); } function checkNormal(f) { checkCommon(f); assertEqArray(f.apply(null, ...[[]]), [undefined, undefined, undefined]); assertEqArray(f.apply(null, ...[[1]]), [1, undefined, undefined]); assertEqArray(f.apply(null, ...[[1, 2]]), [1, 2, undefined]); assertEqArray(f.apply(null, ...[[1, 2, 3, 4]]), [1, 2, 3]); assertEqArray(f.apply(null, ...[[undefined]]), [undefined, undefined, undefined]); } checkNormal(function(a, b, c) [a, b, c]); checkNormal((a, b, c) => [a, b, c]); function checkDefault(f) { checkCommon(f); assertEqArray(f.apply(null, ...[[]]), [-1, -2, -3]); assertEqArray(f.apply(null, ...[[1]]), [1, -2, -3]); assertEqArray(f.apply(null, ...[[1, 2]]), [1, 2, -3]); assertEqArray(f.apply(null, ...[[1, 2, 3, 4]]), [1, 2, 3]); assertEqArray(f.apply(null, ...[[undefined]]), [-1, -2, -3]); } checkDefault(function(a = -1, b = -2, c = -3) [a, b, c]); checkDefault((a = -1, b = -2, c = -3) => [a, b, c]); function checkRest(f) { checkCommon(f); assertEqArray(f.apply(null, ...[[]]), []); assertEqArray(f.apply(null, ...[[1]]), [1]); assertEqArray(f.apply(null, ...[[1, 2]]), [1, 2]); assertEqArray(f.apply(null, ...[[1, 2, 3, 4]]), [1, 2, 3, 4]); assertEqArray(f.apply(null, ...[[undefined]]), [undefined]); // other iterable objects assertEqArray(f.apply(null, ...new Map([[["a", "A"], ["b", "B"]]])).map(([k, v]) => k + v), ["aA", "bB"]); } checkRest(function(...x) x); checkRest((...x) => x);