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// |reftest| skip-if(!xulRuntime.shell)
/*
* Any copyright is dedicated to the Public Domain.
*/
var BUGNUMBER = 1135708;
var summary = "Implement the exponentiation operator";
print(BUGNUMBER + ": " + summary);
// Constant folding
assertEq(2 ** 2 ** 3, 256);
assertEq(1 ** 1 ** 4, 1);
// No folding
var two = 2;
var three = 3;
var four = 4;
assertEq(two ** two ** three, 256);
assertEq(1 ** 1 ** four, 1);
// Operator precedence
assertEq(2 ** 3 / 2 ** 3, 1);
assertEq(2 ** 3 * 2 ** 3, 64);
assertEq(2 ** 3 + 2 ** 3, 16);
// With parentheses
assertEq((2 ** 3) ** 2, 64);
assertEq(2 ** (3 ** 2), 512);
// Assignment operator
var x = 2;
assertEq(x **= 2 ** 3, 256);
assertEq(x, 256);
// Loop to test baseline and ION
for (var i=0; i<10000; i++) {
assertEq((2 ** 3) ** 2, 64);
assertEq(2 ** (3 ** 2), 512);
var x = 2;
assertEq(x **= 2 ** 3, 256);
assertEq(x, 256);
}
// Comments should not be confused with exp operator
var a, c, e;
a = c = e = 2;
assertEq(a**/**b**/c/**/**/**d**/e, 16);
// Two stars separated should not parse as exp operator
assertThrowsInstanceOf(function() { return Reflect.parse("2 * * 3"); }, SyntaxError);
// Left-hand side expression must not be a unary expression.
for (let unaryOp of ["delete", "typeof", "void", "+", "-", "!", "~"]) {
assertThrowsInstanceOf(() => eval(unaryOp + " a ** 2"), SyntaxError);
assertThrowsInstanceOf(() => eval(unaryOp + " " + unaryOp + " a ** 2"), SyntaxError);
}
// Test the other |delete| operators (DELETENAME and DELETEEXPR are already tested above).
assertThrowsInstanceOf(() => eval("delete a.name ** 2"), SyntaxError);
assertThrowsInstanceOf(() => eval("delete a[0] ** 2"), SyntaxError);
// Unary expression lhs is valid if parenthesized.
for (let unaryOp of ["delete", "void", "+", "-", "!", "~"]) {
let a = 0;
eval("(" + unaryOp + " a) ** 2");
eval("(" + unaryOp + " " + unaryOp + " a) ** 2");
}
{
let a = {};
(delete a.name) ** 2;
(delete a[0]) ** 2;
}
// Check if error propagation works
var thrower = {
get value() {
throw new Error();
}
};
assertThrowsInstanceOf(function() { return thrower.value ** 2; }, Error);
assertThrowsInstanceOf(function() { return 2 ** thrower.value; }, Error);
assertThrowsInstanceOf(function() { return 2 ** thrower.value ** 2; }, Error);
var convertibleToPrimitive = {
valueOf: function() {
throw new Error("oops");
}
};
assertThrowsInstanceOf(function() { return convertibleToPrimitive ** 3; }, Error);
assertThrowsInstanceOf(function() { return 3 ** convertibleToPrimitive; }, Error);
assertEq(NaN ** 2, NaN);
assertEq(2 ** NaN, NaN);
assertEq(2 ** "3", 8);
assertEq("2" ** 3, 8);
// Reflect.parse generates a correct parse tree for simplest case
var parseTree = Reflect.parse("a ** b");
assertEq(parseTree.body[0].type, "ExpressionStatement");
assertEq(parseTree.body[0].expression.operator, "**");
assertEq(parseTree.body[0].expression.left.name, "a");
assertEq(parseTree.body[0].expression.right.name, "b");
// Reflect.parse generates a tree following the right-associativity rule
var parseTree = Reflect.parse("a ** b ** c");
assertEq(parseTree.body[0].type, "ExpressionStatement");
assertEq(parseTree.body[0].expression.left.name, "a");
assertEq(parseTree.body[0].expression.right.operator, "**");
assertEq(parseTree.body[0].expression.right.left.name, "b");
assertEq(parseTree.body[0].expression.right.right.name, "c");
if (typeof reportCompare === "function")
reportCompare(true, true);