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// Any copyright is dedicated to the Public Domain.
//-----------------------------------------------------------------------------
var BUGNUMBER = 1146136;
var summary =
'Parenthesized "destructuring patterns" are not usable as destructuring ' +
'patterns';
print(BUGNUMBER + ": " + summary);
/**************
* BEGIN TEST *
**************/
// Don't pollute the top-level script with eval references.
var savedEval = this[String.fromCharCode(101, 118, 97, 108)];
function checkError(code, nonstrictErr, strictErr)
{
function helper(exec, prefix, err)
{
var fullCode = prefix + code;
try
{
var f = exec(fullCode);
var error =
"no early error, parsed code <" + fullCode + "> using " + exec.name;
if (typeof f === "function")
{
try
{
f();
error += ", and the function can be called without error";
}
catch (e)
{
error +=", and calling the function throws " + e;
}
}
throw new Error(error);
}
catch (e)
{
assertEq(e instanceof err, true,
"expected " + err.name + ", got " + e + " " +
"for code <" + fullCode + "> when parsed using " + exec.name);
}
}
helper(Function, "", nonstrictErr);
helper(Function, "'use strict'; ", strictErr);
helper(savedEval, "", nonstrictErr);
helper(savedEval, "'use strict'; ", strictErr);
}
// Parenthesized destructuring patterns don't trigger grammar refinement, so we
// get the usual SyntaxError for an invalid assignment target, per
// 12.14.1 second bullet.
checkError("var a, b; ([a, b]) = [1, 2];", SyntaxError, SyntaxError);
checkError("var a, b; ({a, b}) = { a: 1, b: 2 };", SyntaxError, SyntaxError);
// *Nested* parenthesized destructuring patterns, on the other hand, do trigger
// grammar refinement. But subtargets in a destructuring pattern must be
// either object/array literals that match the destructuring pattern refinement
// *or* valid simple assignment targets (or such things with a default, with the
// entire subtarget unparenthesized: |a = 3| is fine, |(a) = 3| is fine for
// destructuring in an expression, |(a = 3)| is forbidden). Parenthesized
// object/array patterns are neither. And so 12.14.5.1 third bullet requires an
// early SyntaxError.
checkError("var a, b; ({ a: ({ b: b }) } = { a: { b: 42 } });", SyntaxError, SyntaxError);
checkError("var a, b; ({ a: { b: (b = 7) } } = { a: {} });", SyntaxError, SyntaxError);
checkError("var a, b; ({ a: ([b]) } = { a: [42] });", SyntaxError, SyntaxError);
checkError("var a, b; [(a = 5)] = [1];", SyntaxError, SyntaxError);
checkError("var a, b; ({ a: (b = 7)} = { b: 1 });", SyntaxError, SyntaxError);
Function("var a, b; [(a), b] = [1, 2];")();
Function("var a, b; [(a) = 5, b] = [1, 2];")();
Function("var a, b; [(arguments), b] = [1, 2];")();
Function("var a, b; [(arguments) = 5, b] = [1, 2];")();
Function("var a, b; [(eval), b] = [1, 2];")();
Function("var a, b; [(eval) = 5, b] = [1, 2];")();
var repair = {}, demolition = {};
Function("var a, b; [(repair.man), b] = [1, 2];")();
Function("var a, b; [(demolition['man']) = 'motel', b] = [1, 2];")();
Function("var a, b; [(demolition['man' + {}]) = 'motel', b] = [1, 2];")(); // evade constant-folding
function classesEnabled()
{
try
{
new Function("class B { constructor() { } }; class D extends B { constructor() { super(); } }");
return true;
}
catch (e) {
if (!(e instanceof SyntaxError))
throw e;
return false;
}
}
if (classesEnabled())
{
Function("var a, b; var obj = { x() { [(super.man), b] = [1, 2]; } };")();
Function("var a, b; var obj = { x() { [(super[8]) = 'motel', b] = [1, 2]; } };")();
Function("var a, b; var obj = { x() { [(super[8 + {}]) = 'motel', b] = [1, 2]; } };")(); // evade constant-folding
}
// As noted above, when the assignment element has an initializer, the
// assignment element must not be parenthesized.
checkError("var a, b; [(repair.man = 17)] = [1];", SyntaxError, SyntaxError);
checkError("var a, b; [(demolition['man'] = 'motel')] = [1, 2];", SyntaxError, SyntaxError);
checkError("var a, b; [(demolition['man' + {}] = 'motel')] = [1];", SyntaxError, SyntaxError); // evade constant-folding
if (classesEnabled())
{
checkError("var a, b; var obj = { x() { [(super.man = 5)] = [1]; } };", SyntaxError, SyntaxError);
checkError("var a, b; var obj = { x() { [(super[8] = 'motel')] = [1]; } };", SyntaxError, SyntaxError);
checkError("var a, b; var obj = { x() { [(super[8 + {}] = 'motel')] = [1]; } };", SyntaxError, SyntaxError); // evade constant-folding
}
checkError("var a, b; [f() = 'ohai', b] = [1, 2];", SyntaxError, SyntaxError);
checkError("var a, b; [(f()) = 'kthxbai', b] = [1, 2];", SyntaxError, SyntaxError);
Function("var a, b; ({ a: (a), b} = { a: 1, b: 2 });")();
Function("var a, b; ({ a: (a) = 5, b} = { a: 1, b: 2 });")();
/******************************************************************************/
if (typeof reportCompare === "function")
reportCompare(true, true);
print("Tests complete");