Added API test case to check if state manager instance works with tri…

…e provided on VM instantiation (opts.state)

package.json

@@ -41,7 +41,7 @@
     "ethereumjs-util": "^6.0.0",
     "fake-merkle-patricia-tree": "^1.0.1",
     "functional-red-black-tree": "^1.0.1",
-    "merkle-patricia-tree": "^2.1.2",
+    "merkle-patricia-tree": "^2.3.2",
     "rustbn.js": "~0.2.0",
     "safe-buffer": "^5.1.1"
   },

tests/api/index.js

@@ -2,13 +2,14 @@ const { promisify } = require('util')
 const tape = require('tape')
 const util = require('ethereumjs-util')
 const Block = require('ethereumjs-block')
+const Trie = require('merkle-patricia-tree/secure')
 const VM = require('../../lib/index')
 const { setupVM } = require('./utils')
 const { setupPreConditions } = require('../util')
 const testData = require('./testdata.json')
 
 tape('VM with fake blockchain', (t) => {
-  t.test('should insantiate without params', (st) => {
+  t.test('should instantiate without params', (st) => {
     const vm = new VM()
     st.ok(vm.stateManager)
     st.deepEqual(vm.stateManager._trie.root, util.KECCAK256_RLP, 'it has default trie')
@@ -22,6 +23,15 @@ tape('VM with fake blockchain', (t) => {
     st.end()
   })
 
+  t.test('should work with trie (state) provided', (st) => {
+    let trie = new Trie()
+    trie.isTestTrie = true
+    let vm = new VM({ state: trie, activatePrecompiles: true })
+    st.notEqual(vm.stateManager._trie.root, util.KECCAK256_RLP, 'it has different root')
+    st.ok(vm.stateManager._trie.isTestTrie, 'it works on trie provided')
+    st.end()
+  })
+
   t.test('should only accept valid chain and fork', (st) => {
     let vm = new VM({ chain: 'ropsten', hardfork: 'byzantium' })
     st.equal(vm.stateManager._common.param('gasPrices', 'ecAdd'), 500)