changed tslint to not thrown error when unused-expression

changed PublicAccount to not thrown error when empty data

Author: Aleix Morgadas

src/model/account/PublicAccount.ts

@@ -18,6 +18,8 @@ import { convert, KeyPair } from 'nem2-library';
 import { NetworkType } from '../blockchain/NetworkType';
 import { Address } from './Address';
 
+const Hash512 = 64;
+
 /**
  * The public account structure contains account's address and public key.
  */
@@ -63,11 +65,11 @@ export class PublicAccount {
      * @return {boolean}  - True if the signature is valid, false otherwise.
      */
     public verifySignature(data: string, signature: string): boolean {
-        if (!data || !signature) {
+        if (!signature) {
             throw new Error('Missing argument');
         }
 
-        if (signature.length !== 128) {
+        if (signature.length / 2 !== Hash512) {
             throw new Error('Signature length is incorrect');
         }
 

test/model/account/Account.spec.ts

@@ -54,6 +54,6 @@ describe('Account', () => {
         const publicAccount = account.publicAccount;
         const signed = account.signData('catapult rocks!');
         expect(publicAccount.verifySignature('catapult rocks!', signed))
-            .to.be.equal(true);
+            .to.be.true;
     });
 });

test/model/account/PublicAccount.spec.ts

@@ -96,15 +96,4 @@ describe('Signature verification', () => {
         // Act & Assert:
         expect(signerPublicAccount.verifySignature(data, signature)).equal(false);
     });
-
-    it('Throw error if signature verification is missing a parameter', () => {
-        // Arrange:
-        const signerPublicAccount = PublicAccount.createFromPublicKey('22816F825B4CACEA334723D51297D8582332D8B875A5829908AAE85831ABB508',
-            NetworkType.MIJIN_TEST);
-        const data = '';
-        const signature = 'B01DCA6484026C2ECDF3C822E64DEAAFC15EBCCE337EEE209C28513CB5351CDED8863A8E7B855CD471B55C91FAE611C548625C9A5916A555A24F72F3526FA508';// tslint:disable-line
-
-        // Act & Assert:
-        expect(() => { signerPublicAccount.verifySignature(data, signature); }).to.throw('Missing argument');
-    });
 });

tslint.json

@@ -73,7 +73,7 @@
     "no-switch-case-fall-through": true,
     "no-trailing-whitespace": true,
     "no-unnecessary-initializer": true,
-    "no-unused-expression": true,
+    "no-unused-expression": false,
     "no-use-before-declare": true,
     "no-var-keyword": true,
     "object-literal-sort-keys": false,