Fix bug in bytesToBase58btcMultibase() and add tests

Signed-off-by: Frank Hinek <[email protected]>

packages/crypto/src/utils.ts

@@ -27,7 +27,7 @@ export function base64UrlToBytes(base64urlString: string): Uint8Array {
 export function bytesToBase58btcMultibase(header: Uint8Array, bytes: Uint8Array): string {
   const multibaseBytes = new Uint8Array(header.length + bytes.length);
   multibaseBytes.set(header);
-  multibaseBytes.set(bytes);
+  multibaseBytes.set(bytes, header.length);
 
   return base58btc.encode(multibaseBytes);
 }

packages/crypto/tests/utils.spec.ts

@@ -0,0 +1,32 @@
+import { expect } from 'chai';
+
+import { bytesToBase58btcMultibase } from '../src/utils.js';
+
+describe('Crypto Utils', () => {
+  describe('bytesToBase58btcMultibase()', () => {
+    it('returns a multibase encoded string', () => {
+    // Test Vector 1.
+      const input = {
+        header : new Uint8Array([0x00, 0x00]),
+        data   : new Uint8Array([0x00, 0x00])
+      };
+      const output = 'z1111';
+      const encoded = bytesToBase58btcMultibase(input.header, input.data);
+      expect(encoded).to.be.a.string;
+      expect(encoded.substring(0, 1)).to.equal('z');
+      expect(encoded).to.deep.equal(output);
+    });
+
+    it('returns multibase encoded value with specified header', () => {
+    // Test Vector 1.
+      const input = {
+        header : new Uint8Array([0x01, 0x02]),
+        data   : new Uint8Array([3, 4, 5, 6, 7])
+      };
+      const output = 'z3DUyZY2dc';
+
+      const encoded = bytesToBase58btcMultibase(input.header, input.data);
+      expect(encoded).to.deep.equal(output);
+    });
+  });
+});