fix: unset hash128 fields using AccountSet (#2156)

packages/ripple-binary-codec/src/types/hash-128.ts

@@ -9,8 +9,25 @@ class Hash128 extends Hash {
   static readonly ZERO_128: Hash128 = new Hash128(Buffer.alloc(Hash128.width))
 
   constructor(bytes: Buffer) {
+    if (bytes && bytes.byteLength === 0) {
+      bytes = Hash128.ZERO_128.bytes
+    }
+
     super(bytes ?? Hash128.ZERO_128.bytes)
   }
+
+  /**
+   * Get the hex representation of a hash-128 bytes, allowing unset
+   *
+   * @returns hex String of this.bytes
+   */
+  toHex(): string {
+    const hex = this.toBytes().toString('hex').toUpperCase()
+    if (/^0+$/.exec(hex)) {
+      return ''
+    }
+    return hex
+  }
 }
 
 export { Hash128 }

packages/ripple-binary-codec/test/hash.test.js

@@ -1,7 +1,33 @@
 const { coreTypes } = require('../dist/types')
-const { Hash160, Hash256, AccountID, Currency } = coreTypes
+const { Hash128, Hash160, Hash256, AccountID, Currency } = coreTypes
 const { Buffer } = require('buffer/')
 
+describe('Hash128', function () {
+  test('has a static width member', function () {
+    expect(Hash128.width).toBe(16)
+  })
+  test('can be unset', function () {
+    const h1 = Hash128.from('')
+    expect(h1.toJSON()).toBe('')
+  })
+  test('can be compared against another', function () {
+    const h1 = Hash128.from('100000000000000000000000000000000')
+    const h2 = Hash128.from('200000000000000000000000000000000')
+    const h3 = Hash128.from('000000000000000000000000000000003')
+    expect(h1.lt(h2)).toBe(true)
+    expect(h3.lt(h2)).toBe(true)
+    expect(h2.gt(h1)).toBe(true)
+    expect(h1.gt(h3)).toBe(true)
+  })
+  test('throws when constructed from invalid hash length', () => {
+    expect(() => Hash128.from('1000000000000000000000000000000')).toThrow(
+      'Invalid Hash length 15',
+    )
+    expect(() => Hash128.from('10000000000000000000000000000000000')).toThrow(
+      'Invalid Hash length 17',
+    )
+  })
+})
 describe('Hash160', function () {
   test('has a static width member', function () {
     expect(Hash160.width).toBe(20)