diff --git a/test/utils.js b/test/utils.js
index fa52869..603d8a7 100644
--- a/test/utils.js
+++ b/test/utils.js
@@ -23,14 +23,19 @@ const TYPE_TEST_BASE = [
   new Uint32Array([1, 2, 3]),
   100n,
   new Set([1, 2, 3]),
+  new Map([['aa', 'bb']]),
   new Uint8ClampedArray([1, 2, 3]),
   new Int16Array([1, 2, 3]),
+  new Float32Array([1]),
+  new BigInt64Array([1n, 2n, 3n]),
   new ArrayBuffer(100),
   new DataView(new ArrayBuffer(100)),
   { constructor: { name: 'Uint8Array' }, length: '1e30' },
   () => {},
   async () => {},
   class Test {},
+  Symbol.for('a'),
+  new Proxy(new Uint8Array(), {}),
 ];
 
 const TYPE_TEST_OPT = [
@@ -47,7 +52,8 @@ const TYPE_TEST_OPT = [
 
 const TYPE_TEST_NOT_BOOL = [false, true];
 const TYPE_TEST_NOT_BYTES = ['', 'test', '1', new Uint8Array([]), new Uint8Array([1, 2, 3])];
-const TYPE_TEST_NOT_STR = [
+const TYPE_TEST_NOT_HEX = [
+  '0xbe',
   ' 1 2 3 4 5',
   '010203040x',
   'abcdefgh',
@@ -58,15 +64,17 @@ const TYPE_TEST_NOT_STR = [
 const TYPE_TEST_NOT_INT = [-0.0, 0, 1];
 
 const TYPE_TEST = {
-  int: TYPE_TEST_BASE.concat(TYPE_TEST_NOT_BOOL).concat(TYPE_TEST_NOT_BYTES),
-  bytes: TYPE_TEST_BASE.concat(TYPE_TEST_NOT_INT).concat(TYPE_TEST_NOT_BOOL),
-  boolean: TYPE_TEST_BASE.concat(TYPE_TEST_NOT_INT).concat(TYPE_TEST_NOT_BYTES),
-  hex: TYPE_TEST_BASE.concat(TYPE_TEST_NOT_INT, TYPE_TEST_NOT_BOOL, TYPE_TEST_NOT_STR),
+  int: TYPE_TEST_BASE.concat(TYPE_TEST_NOT_BOOL, TYPE_TEST_NOT_BYTES),
+  bytes: TYPE_TEST_BASE.concat(TYPE_TEST_NOT_INT, TYPE_TEST_NOT_BOOL),
+  boolean: TYPE_TEST_BASE.concat(TYPE_TEST_NOT_INT, TYPE_TEST_NOT_BYTES),
+  hex: TYPE_TEST_BASE.concat(TYPE_TEST_NOT_INT, TYPE_TEST_NOT_BOOL, TYPE_TEST_NOT_HEX),
   opts: TYPE_TEST_OPT,
-  hash: TYPE_TEST_BASE.concat(TYPE_TEST_NOT_BOOL)
-    .concat(TYPE_TEST_NOT_INT)
-    .concat(TYPE_TEST_NOT_BYTES)
-    .concat(TYPE_TEST_OPT),
+  hash: TYPE_TEST_BASE.concat(
+    TYPE_TEST_NOT_BOOL,
+    TYPE_TEST_NOT_INT,
+    TYPE_TEST_NOT_BYTES,
+    TYPE_TEST_OPT
+  ),
 };
 
 function median(list) {
diff --git a/test/utils.test.js b/test/utils.test.js
index 336acbe..0ee999a 100644
--- a/test/utils.test.js
+++ b/test/utils.test.js
@@ -5,21 +5,27 @@ const { TYPE_TEST } = require('./utils');
 const { byteSwap, byteSwapIfBE, byteSwap32, isLE, hexToBytes, bytesToHex } = require('../utils');
 
 describe('utils', () => {
+  const staticHexVectors = [
+    { bytes: Uint8Array.from([]), hex: '' },
+    { bytes: Uint8Array.from([0xbe]), hex: 'be' },
+    { bytes: Uint8Array.from([0xca, 0xfe]), hex: 'cafe' },
+    { bytes: Uint8Array.from(new Array(1024).fill(0x69)), hex: '69'.repeat(1024) },
+  ];
   should('hexToBytes', () => {
+    for (let v of staticHexVectors) deepStrictEqual(hexToBytes(v.hex), v.bytes);
     for (let v of TYPE_TEST.hex) {
-      throws(() => {
-        hexToBytes(v);
-      });
+      throws(() => hexToBytes(v));
     }
   });
   should('bytesToHex', () => {
+    for (let v of staticHexVectors) deepStrictEqual(bytesToHex(v.bytes), v.hex);
     for (let v of TYPE_TEST.bytes) {
-      throws(() => {
-        bytesToHex(v);
-      });
+      throws(() => bytesToHex(v));
     }
   });
+});
 
+describe('utils etc', () => {
   // Here goes test for tests...
   should(`Test generator`, () => {
     deepStrictEqual(