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load(libdir + 'asserts.js');
load(libdir + 'eqArrayHelper.js');
var arrayPattern = '[a = 1, b = 2, c = 3, d = 4, e = 5, f = 6]';
var objectPattern = '{0: a = 1, 1: b = 2, 2: c = 3, 3: d = 4, 4: e = 5, 5: f = 6}';
var objectPatternShorthand = '{a = 1, b = 2, c = 3, d = 4, e = 5, f = 6}';
var nestedPattern = '{a: a = 1, b: [b = 2] = [], c: {c: [c]} = {c: [3]}, d: {d, e} = {d: 4, e: 5}, f: f = 6}';
function testAll(fn) {
assertEqArray(fn(arrayPattern, []), [1, 2, 3, 4, 5, 6]);
assertEqArray(fn(arrayPattern, [2, 3, 4, 5, 6, 7, 8, 9]), [2, 3, 4, 5, 6, 7]);
assertEqArray(fn(arrayPattern, [undefined, 0, false, null, "", undefined]), [1, 0, false, null, "", 6]);
assertEqArray(fn(arrayPattern, [0, false]), [0, false, 3, 4, 5, 6]);
assertEqArray(fn(objectPattern, []), [1, 2, 3, 4, 5, 6]);
assertEqArray(fn(objectPattern, [2, 3, 4, 5, 6, 7, 8, 9]), [2, 3, 4, 5, 6, 7]);
assertEqArray(fn(objectPattern, [undefined, 0, false, null, "", undefined]), [1, 0, false, null, "", 6]);
assertEqArray(fn(objectPattern, [0, false]), [0, false, 3, 4, 5, 6]);
assertEqArray(fn(objectPatternShorthand, {}), [1, 2, 3, 4, 5, 6]);
assertEqArray(fn(objectPatternShorthand, {a: 2, b: 3, c: 4, d: 5, e: 6, f: 7, g: 8, h: 9}), [2, 3, 4, 5, 6, 7]);
assertEqArray(fn(objectPatternShorthand, {a: undefined, b: 0, c: false, d: null, e: "", f: undefined}),
[1, 0, false, null, "", 6]);
assertEqArray(fn(objectPatternShorthand, {a: 0, b: false}), [0, false, 3, 4, 5, 6]);
assertEqArray(fn(nestedPattern, {}), [1, 2, 3, 4, 5, 6]);
assertEqArray(fn(nestedPattern, {a: 2, b: [], c: undefined}), [2, 2, 3, 4, 5, 6]);
assertEqArray(fn(nestedPattern, {a: undefined, b: [3], c: {c: [4]}}), [1, 3, 4, 4, 5, 6]);
assertEqArray(fn(nestedPattern, {a: undefined, b: [3], c: {c: [4]}, d: {d: 5, e: 6}}), [1, 3, 4, 5, 6, 6]);
}
function testVar(pattern, input) {
return new Function('input',
'var ' + pattern + ' = input;' +
'return [a, b, c, d, e, f];'
)(input);
}
testAll(testVar);
function testLet(pattern, input) {
return new Function('input',
'let ' + pattern + ' = input;' +
'return [a, b, c, d, e, f];'
)(input);
}
testAll(testLet);
function testConst(pattern, input) {
return new Function('input',
'const ' + pattern + ' = input;' +
'return [a, b, c, d, e, f];'
)(input);
}
testAll(testConst);
function testGlobal(pattern, input) {
return new Function('input',
'(' + pattern + ' = input);' +
'return [a, b, c, d, e, f];'
)(input);
}
testAll(testGlobal);
function testClosure(pattern, input) {
return new Function('input',
'var rest; (function () {' +
'(' + pattern + ' = input);' +
'})();' +
'return [a, b, c, d, e, f];'
)(input);
}
testAll(testClosure);
function testArgument(pattern, input) {
return new Function('input',
'return (function (' + pattern + ') {' +
'return [a, b, c, d, e, f]; })(input);'
)(input);
}
testAll(testArgument);
function testArgumentFunction(pattern, input) {
return new Function(pattern,
'return [a, b, c, d, e, f];'
)(input);
}
testAll(testArgumentFunction);
function testThrow(pattern, input) {
return new Function('input',
'try { throw input }' +
'catch(' + pattern + ') {' +
'return [a, b, c, d, e, f]; }'
)(input);
}
testAll(testThrow);
// test global const
const [ca = 1, cb = 2] = [];
assertEq(ca, 1);
assertEq(cb, 2);
const {a: {a: cc = 3} = {a: undefined}} = {};
assertEq(cc, 3);
// test that the assignment happens in source order
var a = undefined, b = undefined, c = undefined;
({a: a = 1, c: c = 2, b: b = 3} = {
get a() {
assertEq(a, undefined);
assertEq(c, undefined);
assertEq(b, undefined);
return undefined;
},
get b() {
assertEq(a, 1);
assertEq(c, 2);
assertEq(b, undefined);
return 4;
},
get c() {
assertEq(a, 1);
assertEq(c, undefined);
assertEq(b, undefined);
return undefined;
}
});
assertEq(b, 4);
assertThrowsInstanceOf(() => { var {a: {a} = null} = {}; }, TypeError);
assertThrowsInstanceOf(() => { var [[a] = 2] = []; }, TypeError);
// destructuring assignment might have duplicate variable names.
var [a = 1, a = 2] = [3];
assertEq(a, 2);
// assignment to properties of default params
[a = {y: 2}, a.x = 1] = [];
assertEq(typeof a, 'object');
assertEq(a.x, 1);
assertEq(a.y, 2);
// defaults are evaluated even if there is no binding
var evaled = false;
({a: {} = (evaled = true, {})} = {});
assertEq(evaled, true);
evaled = false;
assertThrowsInstanceOf(() => { [[] = (evaled = true, 2)] = [] }, TypeError);
assertEq(evaled, true);
assertThrowsInstanceOf(() => new Function('var [...rest = defaults] = [];'), SyntaxError);
new Function(`
b = undefined;
for (var [a, b = 10] in " ") {}
assertEq(b, 10);`)();
new Function(`
b = undefined;
for (let [a, c = 10] in " ") { b = c; }
assertEq(b, 10);`)();
new Function(`
b = undefined;
for (let [a, c = (x => y)] in " ") { b = c; }
assertEq(typeof b, "function");`)();
new Function(`
b = undefined;
for (let [a, __proto__ = 10] in " ") { b = __proto__; }
assertEq(b, 10);`)();
new Function(`
b = undefined;
for (let [a, __proto__ = (x => y)] in " ") { b = __proto__; }
assertEq(typeof b, "function");`)();
new Function(`
b = undefined;
for (var {1: b = 10} in " ") {}
assertEq(b, 10);`)();
new Function(`
b = undefined;
for (let {1: c = 10} in " ") { b = c; }
assertEq(b, 10);`)();
new Function(`
b = undefined;
for (let { c = 10 } in " ") { b = c; }
assertEq(b, 10);`)();
new Function(`
b = undefined;
assertEq(Number.prototype.a, undefined);
for (var { a: c = (x => y) } in [{}]) { b = c; }
assertEq(typeof b, "function");`)();
new Function(`
b = undefined;
Object.defineProperty(String.prototype, "__proto__",
{ value: undefined, configurable: true });
for (var { __proto__: c = (x => y) } in [{}]) { b = c; }
delete String.prototype.__proto__;
assertEq(typeof b, "function");`)();
new Function(`
b = undefined;
for (var { a: c = (x => y) } of [{ a: undefined }]) { b = c; }
assertEq(typeof b, "function");`)();
new Function(`
b = undefined;
for (var { __proto__: c = (x => y) } of [{ ["__proto__"]: undefined }]) { b = c; }
assertEq(typeof b, "function");`)();
new Function(`
b = undefined;
var ts = Function.prototype.toString;
Function.prototype.toString = () => 'hi';
String.prototype.hi = 42;
for (var { [(x => y)]: c } in [0]) { b = c; }
Function.prototype.toString = ts;
delete String.prototype.hi;
assertEq(b, 42);`)();
new Function(`
b = undefined;
var ts = Function.prototype.toString;
Function.prototype.toString = () => 'hi';
String.prototype.hi = 42;
for (var { [(x => y)]: __proto__ } in [0]) { b = __proto__; }
Function.prototype.toString = ts;
delete String.prototype.hi;
assertEq(b, 42);`)();
new Function(`
b = undefined;
var ts = Function.prototype.toString;
Function.prototype.toString = () => 'hi';
for (var { [(x => y)]: c } of [{ 'hi': 42 }]) { b = c; }
Function.prototype.toString = ts;
assertEq(b, 42);`)();
new Function(`
b = undefined;
var ts = Function.prototype.toString;
Function.prototype.toString = () => 'hi';
for (var { [(x => y)]: __proto__ } of [{ hi: 42 }]) { b = __proto__; }
Function.prototype.toString = ts;
assertEq(b, 42);`)();
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