Merge pull request #5020 from MetaMask/FixMigration28

Fixes migration 28

app/scripts/migrations/028.js

@@ -25,8 +25,8 @@ function transformState (state) {
   const newState = state
 
   if (newState.PreferencesController) {
-    if (newState.PreferencesController.tokens) {
-      const identities = newState.TransactionController.identities
+    if (newState.PreferencesController.tokens && newState.PreferencesController.identities) {
+      const identities = newState.PreferencesController.identities
       const tokens = newState.PreferencesController.tokens
       newState.PreferencesController.accountTokens = {}
       for (const identity in identities) {

test/unit/migrations/028-test.js

@@ -0,0 +1,46 @@
+const assert = require('assert')
+const migration28 = require('../../../app/scripts/migrations/028')
+
+const oldStorage = {
+  'meta': {},
+  'data': {
+    'PreferencesController': {
+      'tokens': [{address: '0xa', symbol: 'A', decimals: 4}, {address: '0xb', symbol: 'B', decimals: 4}],
+      'identities': {
+        '0x6d14': {},
+        '0x3695': {},
+      },
+    },
+  },
+}
+
+describe('migration #28', () => {
+  it('should add corresponding tokens to accountTokens', (done) => {
+    migration28.migrate(oldStorage)
+      .then((newStorage) => {
+        const newTokens = newStorage.data.PreferencesController.tokens
+        const newAccountTokens = newStorage.data.PreferencesController.accountTokens
+
+        const testTokens = [{address: '0xa', symbol: 'A', decimals: 4}, {address: '0xb', symbol: 'B', decimals: 4}]
+        assert.equal(newTokens.length, 0, 'tokens is expected to have the length of 0')
+        assert.equal(newAccountTokens['0x6d14']['mainnet'].length, 2, 'tokens for address is expected to have the length of 2')
+        assert.equal(newAccountTokens['0x3695']['mainnet'].length, 2, 'tokens for address is expected to have the length of 2')
+        assert.equal(Object.keys(newAccountTokens).length, 2, 'account tokens should be created for all identities')
+        assert.deepEqual(newAccountTokens['0x6d14']['mainnet'], testTokens, 'tokens for address should be the same than before')
+        assert.deepEqual(newAccountTokens['0x3695']['mainnet'], testTokens, 'tokens for address should be the same than before')
+        done()
+      })
+      .catch(done)
+  })
+
+  it('should successfully migrate first time state', (done) => {
+    migration28.migrate({
+      meta: {},
+      data: require('../../../app/scripts/first-time-state'),
+    })
+      .then((migratedData) => {
+        assert.equal(migratedData.meta.version, migration28.version)
+        done()
+      }).catch(done)
+  })
+})