watchAsset returns result wether token was added or not

app/scripts/background.js

@@ -256,7 +256,7 @@ function setupController (initState, initLangCode) {
     showUnconfirmedMessage: triggerUi,
     unlockAccountMessage: triggerUi,
     showUnapprovedTx: triggerUi,
-    showAddTokenUi: triggerUi,
+    showWatchAssetUi: showWatchAssetUi,
     // initial state
     initState,
     // initial locale code
@@ -444,6 +444,24 @@ function triggerUi () {
   })
 }
 
+/**
+ * Opens the browser popup for user confirmation of watchAsset
+ * then it waits until user interact with the UI
+ */
+function showWatchAssetUi () {
+  triggerUi()
+  return new Promise(
+    (resolve) => {
+      var interval = setInterval(() => {
+        if (!notificationIsOpen) {
+          clearInterval(interval)
+          resolve()
+        }
+      }, 1000)
+    }
+  )
+}
+
 // On first install, open a window to MetaMask website to how-it-works.
 extension.runtime.onInstalled.addListener(function (details) {
   if ((details.reason === 'install') && (!METAMASK_DEBUG)) {

app/scripts/controllers/preferences.js

@@ -41,7 +41,7 @@ class PreferencesController {
     this.diagnostics = opts.diagnostics
     this.network = opts.network
     this.store = new ObservableStore(initState)
-    this.showAddTokenUi = opts.showAddTokenUi
+    this.showWatchAssetUi = opts.showWatchAssetUi
     this._subscribeProviderType()
   }
 // PUBLIC METHODS
@@ -82,13 +82,12 @@ class PreferencesController {
    * @param {Function} - next
    * @param {Function} - end
    */
-  requestAddToken (req, res, next, end) {
+  async requestWatchAsset (req, res, next, end) {
     if (req.method === 'metamask_watchAsset') {
       const { type, options } = req.params
       switch (type) {
         case 'ERC20':
-          this._handleWatchAssetERC20(options, res)
-          res.result = options.address
+          res.result = await this._handleWatchAssetERC20(options)
           end()
           break
         default:
@@ -521,17 +520,20 @@ class PreferencesController {
   /**
    * Handle the suggestion of an ERC20 asset through `watchAsset`
    * *
-   * @param {Object} options Parameters according to addition of ERC20 token
+   * @param {Boolean} assetAdded Boolean according to addition of ERC20 token
    *
    */
-  _handleWatchAssetERC20 (options) {
+  async _handleWatchAssetERC20 (options) {
     // TODO handle bad parameters
     const { address, symbol, decimals, imageUrl } = options
     const rawAddress = address
     this._validateSuggestedTokenParams({ rawAddress, symbol, decimals })
     const tokenOpts = { rawAddress, decimals, symbol, imageUrl }
     this.addSuggestedToken(tokenOpts)
-    this.showAddTokenUi()
+    return this.showWatchAssetUi().then(() => {
+      const tokenAddresses = this.getTokens().filter(token => token.address === normalizeAddress(rawAddress))
+      return tokenAddresses.length > 0
+    })
   }
 }
 

app/scripts/metamask-controller.js

@@ -88,7 +88,7 @@ module.exports = class MetamaskController extends EventEmitter {
     this.preferencesController = new PreferencesController({
       initState: initState.PreferencesController,
       initLangCode: opts.initLangCode,
-      showAddTokenUi: opts.showAddTokenUi,
+      showWatchAssetUi: opts.showWatchAssetUi,
       network: this.networkController,
     })
 
@@ -1241,7 +1241,7 @@ module.exports = class MetamaskController extends EventEmitter {
     engine.push(createOriginMiddleware({ origin }))
     engine.push(createLoggerMiddleware({ origin }))
     engine.push(filterMiddleware)
-    engine.push(this.preferencesController.requestAddToken.bind(this.preferencesController))
+    engine.push(this.preferencesController.requestWatchAsset.bind(this.preferencesController))
     engine.push(createProviderMiddleware({ provider: this.provider }))
 
     // setup connection