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// Test cases for arguments.length optimization.
function f1() {
return arguments.length;
}
function f2(a, b, c) {
return arguments.length;
}
// arrow functions don't have their own arguments, and so capture the enclosing
// scope.
function f3(a, b, c, d) {
return (() => arguments.length)();
}
// Test a function which mutates arguments.length
function f4(a, b, c, d) {
arguments.length = 42;
return arguments.length;
}
// Manually read out arguments; should disable the length opt
function f5() {
for (var i = 0; i < arguments.length; i++) {
if (arguments[i] == 10) { return true }
}
return false;
}
function f6() {
function inner() {
return arguments.length;
}
return inner(1, 2, 3);
}
// edge cases of the arguments bindings:
function f7() {
var arguments = 42;
return arguments;
}
function f8() {
var arguments = [1, 2];
return arguments.length;
}
function f9() {
eval("arguments.length = 42");
return arguments.length;
}
function test() {
assertEq(f1(), 0);
assertEq(f1(1), 1);
assertEq(f1(1, 2), 2);
assertEq(f1(1, 2, 3), 3);
assertEq(f2(), 0);
assertEq(f2(1, 2, 3), 3);
assertEq(f3(), 0);
assertEq(f3(1, 2, 3), 3);
assertEq(f4(), 42);
assertEq(f4(1, 2, 3), 42);
assertEq(f5(), false);
assertEq(f5(1, 2, 3, 10), true);
assertEq(f5(1, 2, 3, 10, 20), true);
assertEq(f5(1, 2, 3, 9, 20, 30), false);
assertEq(f6(), 3)
assertEq(f6(1, 2, 3, 4), 3)
assertEq(f7(), 42);
assertEq(f8(), 2);
assertEq(f9(), 42);
}
test();
if (typeof reportCompare === "function")
reportCompare(0, 0, "ok");