test_primitive_wrappers.js
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test_primitive_wrappers.js
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	// Test primitive wrapper objects with SLOT_PRIMITIVE

	let passed = 0;
	let failed = 0;

	function test(name, condition) {
	if (condition) {
	console.log("✓", name);
	passed++;
	} else {
	console.log("✗", name);
	failed++;
	}
	}

	// String wrapper
	let s = new String("hello");
	test("String wrapper typeof", typeof s === "object");
	test("String wrapper + concat", s + " world" === "hello world");
	test("String wrapper length", s.length === 5);
	test("String wrapper valueOf", s.valueOf() === "hello");

	// Number wrapper
	let n = new Number(42);
	test("Number wrapper typeof", typeof n === "object");
	test("Number wrapper + arithmetic", n + 8 === 50);
	test("Number wrapper valueOf", n.valueOf() === 42);

	// Boolean wrapper
	let b = new Boolean(true);
	test("Boolean wrapper typeof", typeof b === "object");
	test("Boolean wrapper is truthy", !!b === true);
	test("Boolean wrapper valueOf", b.valueOf() === true);

	// Slot should be hidden from enumeration
	let sKeys = Object.keys(s);
	test("String keys excludes internal slot", !sKeys.includes("__primitive_value__"));

	let nKeys = Object.keys(n);
	test("Number keys excludes internal slot", !nKeys.includes("__primitive_value__"));

	// Object() wrapping primitives
	let wrapped = Object("test");
	test("Object(string) is object", typeof wrapped === "object");
	test("Object(string) valueOf", wrapped.valueOf() === "test");

	console.log("\nResults:", passed, "passed,", failed, "failed");