feat(util): 🎸 add another Uint8Array comparison function

Author: streamich

src/util/buffers/cmpUint8Array2.ts

@@ -1,3 +1,11 @@
+/**
+ * Compares two `Uint8Arrays` byte-by-byte. Returns a negative number if `a` is
+ * less than `b`, a positive number if `a` is greater than `b`, or 0 if `a` is
+ * equal to `b`.
+ *
+ * @returns A negative number if a is less than b, a positive number if a is
+ *         greater than b, or 0 if a is equal to b.
+ */
 export const cmpUint8Array2 = (a: Uint8Array, b: Uint8Array): number => {
   const len1 = a.length;
   const len2 = b.length;

src/util/buffers/cmpUint8Array3.ts

@@ -0,0 +1,19 @@
+/**
+ * Compares two `Uint8Arrays`, first by length, then by each byte. Returns a
+ * negative number if `a` is less than `b`, a positive number if `a` is greater
+ * than `b`, or 0 if `a` is equal to `b`.
+ *
+ * @returns A negative number if a is less than b, a positive number if a is
+ *          greater than b, or 0 if a is equal to b.
+ */
+export const cmpUint8Array3 = (a: Uint8Array, b: Uint8Array): number => {
+  const len1 = a.length;
+  const len2 = b.length;
+  const diff = len1 - len2;
+  if (diff !== 0) return diff;
+  for (let i = 0; i < len1; i++) {
+    const diff = a[i] - b[i];
+    if (diff !== 0) return diff;
+  }
+  return 0;
+};