| load(libdir + 'iteration.js'); |
| |
| let makeCall = farg => Function("f", "arg", "return f(" + farg + ");"); |
| let makeFunCall = farg => Function("f", "arg", "return f.call(null, " + farg + ");"); |
| let makeNew = farg => Function("f", "arg", "return new f(" + farg + ").length;"); |
| |
| function checkLength(f, makeFn) { |
| assertEq(makeFn("...[1, 2, 3]")(f), 3); |
| assertEq(makeFn("1, ...[2], 3")(f), 3); |
| assertEq(makeFn("1, ...[2], ...[3]")(f), 3); |
| assertEq(makeFn("1, ...[2, 3]")(f), 3); |
| assertEq(makeFn("1, ...[], 2, 3")(f), 3); |
| |
| assertEq(makeFn("...[1]")(f), 1); |
| assertEq(makeFn("...[1, 2]")(f), 2); |
| assertEq(makeFn("...[1, 2, 3, 4]")(f), 4); |
| assertEq(makeFn("1, ...[2, 3, 4], 5")(f), 5); |
| |
| assertEq(makeFn("...[undefined]")(f), 1); |
| |
| // other iterable objects |
| assertEq(makeFn("...arg")(f, new Int32Array([1, 2, 3])), 3); |
| assertEq(makeFn("...arg")(f, "abc"), 3); |
| assertEq(makeFn("...arg")(f, [1, 2, 3][Symbol.iterator]()), 3); |
| assertEq(makeFn("...arg")(f, new Set([1, 2, 3])), 3); |
| assertEq(makeFn("...arg")(f, new Map([["a", "A"], ["b", "B"], ["c", "C"]])), 3); |
| let itr = {}; |
| itr[Symbol.iterator] = function() { |
| return { |
| i: 1, |
| next: function() { |
| if (this.i < 4) |
| return { value: this.i++, done: false }; |
| else |
| return { value: undefined, done: true }; |
| } |
| }; |
| } |
| assertEq(makeFn("...arg")(f, itr), 3); |
| function* gen() { |
| for (let i = 1; i < 4; i ++) |
| yield i; |
| } |
| assertEq(makeFn("...arg")(f, gen()), 3); |
| } |
| |
| checkLength(function(x) arguments.length, makeCall); |
| checkLength(function(x) arguments.length, makeFunCall); |
| function lengthClass(x) { |
| this.length = arguments.length; |
| } |
| checkLength(lengthClass, makeNew); |