diff --git a/tests/transaction.test.ts b/tests/transaction.test.ts
index 1aded99..67bd3aa 100644
--- a/tests/transaction.test.ts
+++ b/tests/transaction.test.ts
@@ -7,7 +7,9 @@ import { Transaction, blake2b256, secp256k1, address } from '../src'
 // tslint:disable:trailing-comma
 
 describe("transaction", () => {
-    const body: Transaction.Body = {
+
+    // Correct transaction body
+    const correctTransactionBody: Transaction.Body = {
         chainTag: 1,
         blockRef: '0x00000000aabbccdd',
         expiration: 32,
@@ -25,9 +27,29 @@ describe("transaction", () => {
         dependsOn: null,
         nonce: 12345678,
     }
-    const unsigned = new Transaction(body)
+
+    // Correct unsigned transaction
+    const unsigned = new Transaction(correctTransactionBody)
     const unsignedEncoded = Buffer.from('f8540184aabbccdd20f840df947567d83b7b8d80addcb281a71d54fc7b3364ffed82271086000000606060df947567d83b7b8d80addcb281a71d54fc7b3364ffed824e208600000060606081808252088083bc614ec0', 'hex')
 
+    // Delegated transaction
+    const delegated = new Transaction({
+        ...correctTransactionBody,
+        reserved: {
+            features: 1
+        }
+    })
+
+    // Incorrectly delegated transaction
+    const incorrectlyDelegated = new Transaction({
+        ...correctTransactionBody,
+        // Invalid features field
+        reserved: {
+            features: 1,
+            unused: [Buffer.alloc(0), Buffer.alloc(0)]
+        }
+    })
+
     it('unsigned', () => {
         const signingHash = blake2b256(unsigned.encode())
         expect(signingHash.toString('hex')).equal('2a1c25ce0d66f45276a5f308b99bf410e2fc7d5b6ea37a49f2ab9f1da9446478')
@@ -35,9 +57,9 @@ describe("transaction", () => {
 
         expect(unsigned.id).equal(null)
         expect(unsigned.intrinsicGas).equal(37432)
-        expect(new Transaction({ ...body, clauses: [] }).intrinsicGas).equal(21000)
+        expect(new Transaction({ ...correctTransactionBody, clauses: [] }).intrinsicGas).equal(21000)
         expect(new Transaction({
-            ...body,
+            ...correctTransactionBody,
             clauses: [{
                 to: null,
                 value: 0,
@@ -54,26 +76,26 @@ describe("transaction", () => {
     })
 
     it('invalid body', () => {
-        expect(() => { new Transaction({ ...body, chainTag: 256 }).encode() }).to.throw()
-        expect(() => { new Transaction({ ...body, chainTag: -1 }).encode() }).to.throw()
-        expect(() => { new Transaction({ ...body, chainTag: 1.1 }).encode() }).to.throw()
+        expect(() => { new Transaction({ ...correctTransactionBody, chainTag: 256 }).encode() }).to.throw()
+        expect(() => { new Transaction({ ...correctTransactionBody, chainTag: -1 }).encode() }).to.throw()
+        expect(() => { new Transaction({ ...correctTransactionBody, chainTag: 1.1 }).encode() }).to.throw()
 
-        expect(() => { new Transaction({ ...body, blockRef: '0x' }).encode() }).to.throw()
-        expect(() => { new Transaction({ ...body, blockRef: '0x' + '0'.repeat(18) }).encode() }).to.throw()
+        expect(() => { new Transaction({ ...correctTransactionBody, blockRef: '0x' }).encode() }).to.throw()
+        expect(() => { new Transaction({ ...correctTransactionBody, blockRef: '0x' + '0'.repeat(18) }).encode() }).to.throw()
 
-        expect(() => { new Transaction({ ...body, expiration: 2 ** 32 }).encode() }).to.throw()
-        expect(() => { new Transaction({ ...body, expiration: -1 }).encode() }).to.throw()
-        expect(() => { new Transaction({ ...body, expiration: 1.1 }).encode() }).to.throw()
+        expect(() => { new Transaction({ ...correctTransactionBody, expiration: 2 ** 32 }).encode() }).to.throw()
+        expect(() => { new Transaction({ ...correctTransactionBody, expiration: -1 }).encode() }).to.throw()
+        expect(() => { new Transaction({ ...correctTransactionBody, expiration: 1.1 }).encode() }).to.throw()
 
-        expect(() => { new Transaction({ ...body, gasPriceCoef: 256 }).encode() }).to.throw()
-        expect(() => { new Transaction({ ...body, gasPriceCoef: -1 }).encode() }).to.throw()
-        expect(() => { new Transaction({ ...body, gasPriceCoef: 1.1 }).encode() }).to.throw()
+        expect(() => { new Transaction({ ...correctTransactionBody, gasPriceCoef: 256 }).encode() }).to.throw()
+        expect(() => { new Transaction({ ...correctTransactionBody, gasPriceCoef: -1 }).encode() }).to.throw()
+        expect(() => { new Transaction({ ...correctTransactionBody, gasPriceCoef: 1.1 }).encode() }).to.throw()
 
-        expect(() => { new Transaction({ ...body, gas: '0x10000000000000000' }).encode() }).to.throw()
-        expect(() => { new Transaction({ ...body, nonce: '0x10000000000000000' }).encode() }).to.throw()
+        expect(() => { new Transaction({ ...correctTransactionBody, gas: '0x10000000000000000' }).encode() }).to.throw()
+        expect(() => { new Transaction({ ...correctTransactionBody, nonce: '0x10000000000000000' }).encode() }).to.throw()
     })
 
-    const signed = new Transaction(body)
+    const signed = new Transaction(correctTransactionBody)
     const signedEncoded = Buffer.from('f8970184aabbccdd20f840df947567d83b7b8d80addcb281a71d54fc7b3364ffed82271086000000606060df947567d83b7b8d80addcb281a71d54fc7b3364ffed824e208600000060606081808252088083bc614ec0b841f76f3c91a834165872aa9464fc55b03a13f46ea8d3b858e528fcceaf371ad6884193c3f313ff8effbb57fe4d1adc13dceb933bedbf9dbb528d2936203d5511df00', 'hex')
     const privKey = Buffer.from('7582be841ca040aa940fff6c05773129e135623e41acce3e0b8ba520dc1ae26a', 'hex')
     signed.signature = secp256k1.sign(blake2b256(signed.encode()), privKey)
@@ -92,36 +114,18 @@ describe("transaction", () => {
 
         expect(() => Transaction.decode(unsignedEncoded)).to.throw()
         expect(() => Transaction.decode(signedEncoded, true)).to.throw()
+
+        // Encode invalid reserved field
+        const encodedIncorrectlyDelegated = incorrectlyDelegated.encode().toString('hex')
+        Transaction.decode(Buffer.from(encodedIncorrectlyDelegated, "hex"), true)
     })
 
-    const incorrectlySigned = new Transaction(body)
+    const incorrectlySigned = new Transaction(correctTransactionBody)
     incorrectlySigned.signature = Buffer.from([1, 2, 3])
     it('incorrectly signed', () => {
         expect(incorrectlySigned.origin).equal(null)
         expect(incorrectlySigned.id).equal(null)
-    })
-
-
-    const delegated = new Transaction({
-        chainTag: 1,
-        blockRef: '0x00000000aabbccdd',
-        expiration: 32,
-        clauses: [{
-            to: '0x7567d83b7b8d80addcb281a71d54fc7b3364ffed',
-            value: 10000,
-            data: '0x000000606060'
-        }, {
-            to: '0x7567d83b7b8d80addcb281a71d54fc7b3364ffed',
-            value: 20000,
-            data: '0x000000606060'
-        }],
-        gasPriceCoef: 128,
-        gas: 21000,
-        dependsOn: null,
-        nonce: 12345678,
-        reserved: {
-            features: 1
-        }
+        expect(incorrectlySigned.delegator).equal(null)
     })
 
     it('features', () => {
@@ -135,6 +139,7 @@ describe("transaction", () => {
 
         const hash = delegated.signingHash()
         const dhash = delegated.signingHash(addr1)
+        expect(() => delegated.signingHash("INVALID_ADDRESS")).to.throw(Error, 'delegateFor expected address')
 
         const sig = Buffer.concat([
             secp256k1.sign(hash, priv1),