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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
// Ensure that the syntax used in shorthand destructuring with defaults
// e.g. |{x=1, y=2} = {}| properly raises a syntax error within an object
// literal. As per ES6 12.2.6 Object Initializer, "NOTE 3."
const SYNTAX_ERROR_STMTS = [
// expressions
"({x={}={}}),",
"({y={x={}={}={}={}={}={}={}={}}={}}),",
"({a=1, b=2, c=3, x=({}={})}),",
"({x=1, y={z={1}}})",
"({x=1} = {y=1});",
"({x: y={z=1}}={})",
"({x=1}),",
"({z={x=1}})=>{};",
"({x = ({y=1}) => y})",
"(({x=1})) => x",
"({e=[]}==(;",
"({x=1}[-1]);",
"({x=y}[-9])",
"({x=y}.x.z[-9])",
"({x=y}`${-9}`)",
"(new {x=y}(-9))",
"new {x=1}",
"new {x=1}={}",
"typeof {x=1}",
"typeof ({x=1})",
"({x=y, [-9]:0})",
"((({w = x} >(-9)",
"++({x=1})",
"--{x=1}",
"!{x=1}={}",
"delete {x=1}",
"delete ({x=1})",
"delete {x=1} = {}",
"({x=1}.abc)",
"x > (0, {a = b} );",
// declarations
"var x = 0 + {a=1} = {}",
"let o = {x=1};",
"var j = {x=1};",
"var j = {x={y=1}}={};",
"const z = {x=1};",
"const z = {x={y=1}}={};",
"const {x=1};",
"const {x={y=33}}={};",
"var {x=1};",
"let {x=1};",
"let x, y, {z=1}={}, {w=2}, {e=3};",
// array initialization
"[{x=1, y = ({z=2} = {})}];",
// try/catch
"try {throw 'a';} catch ({x={y=1}}) {}",
// if/else
"if ({k: 1, x={y=2}={}}) {}",
"if (false) {} else if (true) { ({x=1}) }",
// switch
"switch ('c') { case 'c': ({x=1}); }",
// for
"for ({x=1}; 1;) {1}",
"for ({x={y=2}}; 1;) {1}",
"for (var x = 0; x < 2; x++) { ({x=1, y=2}) }",
"for (let x=1;{x=1};){}",
"for (let x=1;{x={y=2}};){}",
"for (let x=1;1;{x=1}){}",
"for (let x=1;1;{x={y=2}}){}",
// while
"while ({x=1}) {1};",
"while ({x={y=2}}={}) {1};",
// with
"with ({x=1}) {};",
"with ({x={y=3}={}}) {};",
"with (Math) { ({x=1}) };",
// ternary
"true ? {x=1} : 1;",
"false ? 1 : {x=1};",
"{x=1} ? 2 : 3;",
// assignment
"({x} += {});",
"({x = 1}) = {x: 2};",
]
for (var stmt of SYNTAX_ERROR_STMTS) {
assertThrowsInstanceOf(() => {
Function(stmt);
}, SyntaxError);
}
// A few tricky but acceptable cases:
assertEq((({a = 0}) => a)({}), 0);
assertEq((({a = 0} = {}) => a)({}), 0);
assertEq((({a = 0} = {}) => a)({a: 1}), 1);
{
let x, y;
({x=1} = {});
assertEq(x, 1);
({x=1} = {x: 4});
assertEq(x, 4);
({x=1, y=2} = {})
assertEq(x, 1);
assertEq(y, 2);
}
{
let {x={i=1, j=2}={}}={};
assertDeepEq(x, ({}));
assertEq(i, 1);
assertEq(j, 2);
}
// Default destructuring values, which are variables, should be defined
{
let f = function(a){
return (function({aa = a}){ return aa; })({});
};
assertEq(f(9999), 9999);
}
if (typeof reportCompare == "function")
reportCompare(true, true);