LibJS: Reorganize tests into subfolders

Author: https://github.com/mattco98
Commit: 4c48c9d69d
Pull-request: https://github.com/SerenityOS/serenity/pull/2681
Reviewed-by: https://github.com/linusg

Libraries/LibJS/Tests/JSON.stringify.js

@@ -1,71 +0,0 @@
-load("test-common.js");
-
-try {
-    assert(JSON.stringify.length === 3);
-
-    assertThrowsError(() => {
-        JSON.stringify(5n);
-    }, {
-        error: TypeError,
-        message: "Cannot serialize BigInt value to JSON",
-    });
-
-    const properties = [
-        [5, "5"],
-        [undefined, undefined],
-        [null, "null"],
-        [NaN, "null"],
-        [-NaN, "null"],
-        [Infinity, "null"],
-        [-Infinity, "null"],
-        [true, "true"],
-        [false, "false"],
-        ["test", '"test"'],
-        [new Number(5), "5"],
-        [new Boolean(false), "false"],
-        [new String("test"), '"test"'],
-        [() => {}, undefined],
-        [[1, 2, "foo"], '[1,2,"foo"]'],
-        [{ foo: 1, bar: "baz", qux() {} }, '{"foo":1,"bar":"baz"}'],
-        [
-            {
-                var1: 1,
-                var2: 2,
-                toJSON(key) {
-                    let o = this;
-                    o.var2 = 10;
-                    return o;
-                }
-            },
-            '{"var1":1,"var2":10}',
-        ],
-    ];
-
-    properties.forEach(testCase => {
-        assert(JSON.stringify(testCase[0]) === testCase[1]);
-    });
-
-    let bad1 = {};
-    bad1.foo = bad1;
-    let bad2 = [];
-    bad2[5] = [[[bad2]]];
-
-    let bad3a = { foo: "bar" };
-    let bad3b = [1, 2, bad3a];
-    bad3a.bad = bad3b;
-
-    [bad1, bad2, bad3a].forEach(bad => assertThrowsError(() => {
-        JSON.stringify(bad);
-    }, {
-        error: TypeError,
-        message: "Cannot stringify circular object",
-    }));
-
-    let o = { foo: "bar" };
-    Object.defineProperty(o, "baz", { value: "qux", enumerable: false });
-    assert(JSON.stringify(o) === '{"foo":"bar"}');
-
-    console.log("PASS");
-} catch (e) {
-    console.log("FAIL: " + e);
-}