Adjust Option toHex conversion

packages/types-codec/src/base/Option.spec.ts

@@ -93,17 +93,6 @@ describe('Option', (): void => {
     ).toEqual('hello');
   });
 
-  it('converts correctly from hex with toHex (Bytes)', (): void => {
-    // Option<Bytes> for a parachain head, however, this is effectively an
-    // Option<Option<Bytes>> (hence the length, since it is from storage)
-    const HEX = '0x210100000000000000000000000000000000000000000000000000000000000000000000000000000000011b4d03dd8c01f1049143cf9c4c817e4b167f1d1b83e5c6f0f10d89ba1e7bce';
-
-    // watch the hex prefix and length
-    expect(
-      new Option(registry, Bytes, HEX).toHex().substring(6)
-    ).toEqual(HEX.substring(2));
-  });
-
   it('converts correctly from hex with toNumber (U64)', (): void => {
     const HEX = '0x12345678';
 
@@ -124,8 +113,6 @@ describe('Option', (): void => {
   testDecode('string (without)', undefined, '');
   testDecode('Uint8Array (with)', Uint8Array.from([1, 12, 102, 111, 111]), 'foo');
   testDecode('Uint8Array (without)', Uint8Array.from([0]), '');
-
-  testEncode('toHex', '0x0c666f6f');
   testEncode('toString', 'foo');
   testEncode('toU8a', Uint8Array.from([1, 12, 102, 111, 111]));
 
@@ -177,6 +164,55 @@ describe('Option', (): void => {
     ).toEqual('abcde');
   });
 
+  describe('toHex()', (): void => {
+    it('converts Option<U32> correctly', (): void => {
+      expect(
+        new Option(registry, U32, 0x1234).toHex()
+      ).toEqual('0x00001234');
+    });
+
+    it('converts Option<Option<U32>> correctly', (): void => {
+      expect(
+        new Option(registry, Option.with(U32), 0x1234).toHex()
+      ).toEqual('0x00001234');
+    });
+
+    it('constructs from hex Option<Option<U32>> correctly', (): void => {
+      expect(
+        new Option(registry, Option.with(U32), '0x00001234').toHex()
+      ).toEqual('0x00001234');
+    });
+
+    it('converts Option<Bytes> correctly', (): void => {
+      expect(
+        new Option(registry, Bytes, 'abcde').toHex()
+      ).toEqual('0x6162636465');
+    });
+
+    it('converts Option<Option<Bytes>> correctly', (): void => {
+      expect(
+        new Option(registry, Option.with(Bytes), 'abcde').toHex()
+      ).toEqual('0x6162636465');
+    });
+
+    it('constructs from hex Option<Option<Bytes>> correctly', (): void => {
+      expect(
+        new Option(registry, Option.with(Bytes), '0x6162636465').toHex()
+      ).toEqual('0x6162636465');
+    });
+
+    it('converts correctly from hex with toHex (Bytes)', (): void => {
+      // Option<Bytes> for a parachain head, however, this is effectively an
+      // Option<Option<Bytes>> (hence the length, since it is from storage)
+      const HEX = '0x210100000000000000000000000000000000000000000000000000000000000000000000000000000000011b4d03dd8c01f1049143cf9c4c817e4b167f1d1b83e5c6f0f10d89ba1e7bce';
+
+      // watch the hex prefix and length
+      expect(
+        new Option(registry, Bytes, HEX).toHex()
+      ).toEqual(HEX);
+    });
+  });
+
   describe('utils', (): void => {
     const test = new Option(registry, Text, '1234');
 

packages/types-codec/src/base/Option.ts

@@ -4,7 +4,7 @@
 import type { HexString } from '@polkadot/util/types';
 import type { AnyJson, Codec, CodecClass, DefinitionSetter, Inspect, IOption, IU8a, Registry } from '../types/index.js';
 
-import { identity, isCodec, isNull, isU8a, isUndefined, u8aToHex } from '@polkadot/util';
+import { identity, isCodec, isNull, isU8a, isUndefined } from '@polkadot/util';
 
 import { typeToConstructor } from '../utils/index.js';
 import { Null } from './Null.js';
@@ -177,7 +177,7 @@ export class Option<T extends Codec> implements IOption<T> {
     // the isSome value is correct, however the `isNone` may be problematic
     return this.isNone
       ? '0x'
-      : u8aToHex(this.toU8a().subarray(1));
+      : this.#raw.toHex();
   }
 
   /**