LibJS: Convert some top-level tests to the new system

First test conversions! These look really good :)

Libraries/LibJS/Tests/exponentiation-basic.js

@@ -1,30 +1,37 @@
-load("test-common.js");
+test("regular exponentiation", () => {
+    expect(2 ** 0).toBe(1);
+    expect(2 ** 1).toBe(2);
+    expect(2 ** 2).toBe(4);
+    expect(2 ** 3).toBe(8);
+    expect(3 ** 2).toBe(9);
+    expect(0 ** 0).toBe(1);
+    expect(2 ** 3 ** 2).toBe(512);
+    expect(2 ** (3 ** 2)).toBe(512);
+    expect((2 ** 3) ** 2).toBe(64);
+});
 
-try {
-    assert(2 ** 0 === 1);
-    assert(2 ** 1 === 2);
-    assert(2 ** 2 === 4);
-    assert(2 ** 3 === 8);
-    assert(2 ** -3 === 0.125);
-    assert(3 ** 2 === 9);
-    assert(0 ** 0 === 1);
-    assert(2 ** 3 ** 2 === 512);
-    assert(2 ** (3 ** 2) === 512);
-    assert((2 ** 3) ** 2 === 64);
-    assert("2" ** "3" === 8);
-    assert("" ** [] === 1);
-    assert([] ** null === 1);
-    assert(null ** null === 1);
-    assert(undefined ** null === 1);
-    assert(isNaN(NaN ** 2));
-    assert(isNaN(2 ** NaN));
-    assert(isNaN(undefined ** 2));
-    assert(isNaN(2 ** undefined));
-    assert(isNaN(null ** undefined));
-    assert(isNaN(2 ** "foo"));
-    assert(isNaN("foo" ** 2));
+test("exponentation with negatives", () => {
+    expect(2 ** -3).toBe(0.125);
+    expect((-2) ** 3).toBe(-8);
+    
+    // FIXME: This should fail :)
+    // expect("-2 ** 3").not.toEval();
+});
 
-    console.log("PASS");
-} catch (e) {
-    console.log("FAIL: " + e);
-}
+test("exponentation with non-numeric primitives", () => {
+    expect("2" ** "3").toBe(8);
+    expect("" ** []).toBe(1);
+    expect([] ** null).toBe(1);
+    expect(null ** null).toBe(1);
+    expect(undefined ** null).toBe(1);
+})
+
+test("exponentation that produces NaN", () => {
+    expect(NaN ** 2).toBeNaN();
+    expect(2 ** NaN).toBeNaN();
+    expect(undefined ** 2).toBeNaN();
+    expect(2 ** undefined).toBeNaN();
+    expect(null ** undefined).toBeNaN();
+    expect(2 ** "foo").toBeNaN();
+    expect("foo" ** 2).toBeNaN();
+});