Disallow loading as metamaskNetworkId (#5924)

* transactions - throw an error if a transaction is generated while the network is loading

* add tests for failing when netId is loading

2 files changed, 14 insertions, 3 deletions

diff --git a/app/scripts/controllers/transactions/tx-state-manager.js b/app/scripts/controllers/transactions/tx-state-manager.js
index 72d869fa8..420191d9c 100644
--- a/app/scripts/controllers/transactions/tx-state-manager.js
+++ b/app/scripts/controllers/transactions/tx-state-manager.js
@@ -45,11 +45,13 @@ class TransactionStateManager extends EventEmitter {
     @returns {txMeta} the default txMeta object
   */
   generateTxMeta (opts) {
+    const netId = this.getNetwork()
+    if (netId === 'loading') throw new Error('MetaMask is having trouble connecting to the network')
     return extend({
       id: createId(),
       time: (new Date()).getTime(),
       status: 'unapproved',
-      metamaskNetworkId: this.getNetwork(),
+      metamaskNetworkId: netId,
       loadingDefaults: true,
     }, opts)
   }
diff --git a/test/unit/app/controllers/transactions/tx-controller-test.js b/test/unit/app/controllers/transactions/tx-controller-test.js
index 74161e26c..9000cd364 100644
--- a/test/unit/app/controllers/transactions/tx-controller-test.js
+++ b/test/unit/app/controllers/transactions/tx-controller-test.js
@@ -12,7 +12,7 @@ const { createTestProviderTools, getTestAccounts } = require('../../../../stub/p
 
 const noop = () => true
 const currentNetworkId = 42
-
+const netStore = new ObservableStore(currentNetworkId)
 
 describe('Transaction Controller', function () {
   let txController, provider, providerResultStub, fromAccount
@@ -32,7 +32,7 @@ describe('Transaction Controller', function () {
     txController = new TransactionController({
       provider,
       getGasPrice: function () { return '0xee6b2800' },
-      networkStore: new ObservableStore(currentNetworkId),
+      networkStore: netStore,
       txHistoryLimit: 10,
       blockTracker: blockTrackerStub,
       signTransaction: (ethTx) => new Promise((resolve) => {
@@ -227,6 +227,15 @@ describe('Transaction Controller', function () {
       txController.addUnapprovedTransaction({ from: selectedAddress, to: '0x0d1d4e623D10F9FBA5Db95830F7d3839406C6AF2' })
       .catch(done)
     })
+
+    it('should fail if netId is loading', function (done) {
+      txController.networkStore = new ObservableStore('loading')
+      txController.addUnapprovedTransaction({ from: selectedAddress, to: '0x0d1d4e623D10F9FBA5Db95830F7d3839406C6AF2' })
+      .catch((err) => {
+        if (err.message === 'MetaMask is having trouble connecting to the network') done()
+        else done(err)
+      })
+    })
   })
 
   describe('#addTxGasDefaults', function () {