Prepare for repo merge

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

test/unit-tests/utils/FixedRollingArray-test.ts

@@ -0,0 +1,59 @@
+/*
+Copyright 2024 New Vector Ltd.
+Copyright 2021 The Matrix.org Foundation C.I.C.
+
+SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only
+Please see LICENSE files in the repository root for full details.
+*/
+
+import { FixedRollingArray } from "../../src/utils/FixedRollingArray";
+
+describe("FixedRollingArray", () => {
+    it("should seed the array with the given value", () => {
+        const seed = "test";
+        const width = 24;
+        const array = new FixedRollingArray(width, seed);
+
+        expect(array.value.length).toBe(width);
+        expect(array.value.every((v) => v === seed)).toBe(true);
+    });
+
+    it("should insert at the correct end", () => {
+        const seed = "test";
+        const value = "changed";
+        const width = 24;
+        const array = new FixedRollingArray(width, seed);
+        array.pushValue(value);
+
+        expect(array.value.length).toBe(width);
+        expect(array.value[0]).toBe(value);
+    });
+
+    it("should roll over", () => {
+        const seed = -1;
+        const width = 24;
+        const array = new FixedRollingArray(width, seed);
+
+        const maxValue = width * 2;
+        const minValue = width; // because we're forcing a rollover
+        for (let i = 0; i <= maxValue; i++) {
+            array.pushValue(i);
+        }
+
+        expect(array.value.length).toBe(width);
+
+        for (let i = 1; i < width; i++) {
+            const current = array.value[i];
+            const previous = array.value[i - 1];
+            expect(previous - current).toBe(1);
+
+            if (i === 1) {
+                // eslint-disable-next-line jest/no-conditional-expect
+                expect(previous).toBe(maxValue);
+            } else if (i === width) {
+                // eslint-disable-next-line jest/no-conditional-expect
+                expect(current).toBe(minValue);
+            }
+        }
+    });
+});