michael@0: // Destructuring assignment to eval or arguments in destructuring is a SyntaxError
michael@0: 
michael@0: load(libdir + "asserts.js");
michael@0: 
michael@0: var patterns = [
michael@0:     "[_]",
michael@0:     "[a, b, _]",
michael@0:     "[[_]]",
michael@0:     "[[], [{}, [_]]]",
michael@0:     "{x:_}",
michael@0:     "{x:y, z:_}",
michael@0:     "{0:_}",
michael@0:     "{_}",
michael@0:     //"[..._]"
michael@0: ];
michael@0: 
michael@0: // If the assertion below fails, congratulations! It means you have added
michael@0: // spread operator support to destructuring assignment. Simply uncomment the
michael@0: // "[..._]" case above. Then delete this comment and assertion.
michael@0: assertThrowsInstanceOf(() => Function("[...x] = [1]"), ReferenceError);
michael@0: 
michael@0: for (var pattern of patterns) {
michael@0:     var stmt = pattern + " = obj";
michael@0:     if (stmt[0] == "{")
michael@0:         stmt = "(" + stmt + ")";
michael@0:     stmt += ";"
michael@0: 
michael@0:     // stmt is a legal statement...
michael@0:     Function(stmt);
michael@0: 
michael@0:     // ...but not if you replace _ with one of these two names.
michael@0:     for (var name of ["eval", "arguments"]) {
michael@0:         var s = stmt.replace("_", name);
michael@0:         assertThrowsInstanceOf(() => Function(s), SyntaxError);
michael@0:         assertThrowsInstanceOf(() => eval(s), SyntaxError);
michael@0:         assertThrowsInstanceOf(() => eval("'use strict'; " + s), SyntaxError);
michael@0:     }
michael@0: }