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 // Destructuring assignment to eval or arguments in destructuring is a SyntaxError

 load(libdir + "asserts.js");

 var patterns = [

     "[_]",

     "[a, b, _]",

     "[[_]]",

     "[[], [{}, [_]]]",

     "{x:_}",

     "{x:y, z:_}",

     "{0:_}",

     "{_}",

     //"[..._]"

 ];

 // If the assertion below fails, congratulations! It means you have added

 // spread operator support to destructuring assignment. Simply uncomment the

 // "[..._]" case above. Then delete this comment and assertion.

 assertThrowsInstanceOf(() => Function("[...x] = [1]"), ReferenceError);

 for (var pattern of patterns) {

     var stmt = pattern + " = obj";

     if (stmt[0] == "{")

         stmt = "(" + stmt + ")";

     stmt += ";"

     // stmt is a legal statement...

     Function(stmt);

     // ...but not if you replace _ with one of these two names.

     for (var name of ["eval", "arguments"]) {

         var s = stmt.replace("_", name);

         assertThrowsInstanceOf(() => Function(s), SyntaxError);

         assertThrowsInstanceOf(() => eval(s), SyntaxError);

         assertThrowsInstanceOf(() => eval("'use strict'; " + s), SyntaxError);

     }

 }