refactor: reset state when the flashing flag is set to false (#518)

Currently, we were taking care of resetting the flashing state manually
across several controllers. Now that data mutations live in a single
place, we trigger a flash state reset whenever the flashing flag is set
to false, which reliably handles every case and allows us to forget
about it.

Signed-off-by: Juan Cruz Viotti <jviottidc@gmail.com>

lib/gui/app.js

@@ -147,8 +147,6 @@ app.controller('AppController', function(
       preserveImage: true
 
     });
-
-    this.writer.resetState();
   }
 
   NotifierService.subscribe($scope, 'image-writer:state', function(state) {
@@ -233,7 +231,6 @@ app.controller('AppController', function(
       preserveImage: true
     });
 
-    self.writer.resetState();
     self.success = true;
     AnalyticsService.logEvent('Restart after failure');
   };
@@ -256,7 +253,6 @@ app.controller('AppController', function(
     return self.writer.flash(image, drive).then(function(results) {
 
       if (results.cancelled) {
-        self.writer.resetState();
         return;
       }
 
@@ -283,7 +279,6 @@ app.controller('AppController', function(
         AnalyticsService.logEvent('Flash error');
       }
 
-      self.writer.resetState();
       self.handleError(error);
     })
     .finally(OSWindowProgressService.clear);

lib/gui/models/store.js

@@ -94,7 +94,16 @@ const store = function(state, action) {
     }
 
     case 'SET_FLASHING': {
-      return state.setIn([ 'flash', 'flashing' ], Boolean(action.data));
+      const value = Boolean(action.data);
+      const newState = state.setIn([ 'flash', 'flashing' ], value);
+
+      if (!value) {
+        return store(newState, {
+          type: 'RESET_FLASH_STATE'
+        });
+      }
+
+      return newState;
     }
 
     case 'SELECT_DRIVE': {

lib/gui/modules/image-writer.js

@@ -102,6 +102,40 @@ imageWriter.service('ImageWriterService', function($q, $timeout, SettingsModel,
     });
   };
 
+  /**
+   * @summary Set the flashing state
+   * @function
+   * @private
+   *
+   * @description
+   * This function is extracted for testing purposes.
+   *
+   * @param {Object} state - flashing state
+   *
+   * @example
+   * ImageWriterService.setProgressState({
+   *   type: 'write',
+   *   percentage: 50,
+   *   eta: 15,
+   *   speed: 100000000000
+   * });
+   */
+  this.setProgressState = function(state) {
+    store.dispatch({
+      type: 'SET_FLASH_STATE',
+      data: {
+        type: state.type,
+        progress: state.percentage,
+        eta: state.eta,
+
+        // Transform bytes to megabytes preserving only two decimal places
+        speed: Math.floor(state.speed / 1e+6 * 100) / 100 || 0
+      }
+    });
+
+    NotifierService.emit('image-writer:state', self.state);
+  };
+
   /**
    * @summary Perform write operation
    * @function
@@ -161,23 +195,7 @@ imageWriter.service('ImageWriterService', function($q, $timeout, SettingsModel,
 
     self.setFlashing(true);
 
-    return self.performWrite(image, drive, function(state) {
+    return self.performWrite(image, drive, self.setProgressState).finally(function() {
-
-      store.dispatch({
-        type: 'SET_FLASH_STATE',
-        data: {
-          type: state.type,
-          progress: state.percentage,
-          eta: state.eta,
-
-          // Transform bytes to megabytes preserving only two decimal places
-          speed: Math.floor(state.speed / 1e+6 * 100) / 100 || 0
-        }
-      });
-
-      NotifierService.emit('image-writer:state', self.state);
-
-    }).finally(function() {
       self.setFlashing(false);
     });
   };

lib/gui/pages/finish/controllers/finish.js

@@ -16,7 +16,7 @@
 
 'use strict';
 
-module.exports = function($state, $stateParams, SelectionStateModel, ImageWriterService, AnalyticsService, SettingsModel) {
+module.exports = function($state, $stateParams, SelectionStateModel, AnalyticsService, SettingsModel) {
 
   /**
    * @summary Settings data
@@ -45,7 +45,6 @@ module.exports = function($state, $stateParams, SelectionStateModel, ImageWriter
    */
   this.restart = function(options) {
     SelectionStateModel.clear(options);
-    ImageWriterService.resetState();
     AnalyticsService.logEvent('Restart', options);
     $state.go('main');
   };

lib/gui/pages/finish/finish.js

@@ -30,7 +30,6 @@ const angular = require('angular');
 const MODULE_NAME = 'Etcher.Pages.Finish';
 const FinishPage = angular.module(MODULE_NAME, [
   require('angular-ui-router'),
-  require('../../modules/image-writer'),
   require('../../modules/analytics'),
   require('../../models/selection-state'),
   require('../../models/settings')

tests/gui/modules/image-writer.spec.js

@@ -87,6 +87,33 @@ describe('Browser: ImageWriter', function() {
         m.chai.expect(ImageWriterService.isFlashing()).to.be.false;
       });
 
+      it('should reset the flashing state if set to false', function() {
+        ImageWriterService.setFlashing(true);
+
+        ImageWriterService.setProgressState({
+          type: 'write',
+          percentage: 50,
+          eta: 15,
+          speed: 100000000000
+        });
+
+        $timeout.flush();
+
+        m.chai.expect(ImageWriterService.state).to.not.deep.equal({
+          progress: 0,
+          speed: 0
+        });
+
+        ImageWriterService.setFlashing(false);
+
+        $timeout.flush();
+
+        m.chai.expect(ImageWriterService.state).to.deep.equal({
+          progress: 0,
+          speed: 0
+        });
+      });
+
     });
 
     describe('.flash()', function() {
@@ -103,12 +130,14 @@ describe('Browser: ImageWriter', function() {
         });
 
         it('should set flashing to false when done', function() {
+          ImageWriterService.setFlashing(false);
           ImageWriterService.flash('foo.img', '/dev/disk2');
           $rootScope.$apply();
           m.chai.expect(ImageWriterService.isFlashing()).to.be.false;
         });
 
         it('should prevent writing more than once', function() {
+          ImageWriterService.setFlashing(false);
           ImageWriterService.flash('foo.img', '/dev/disk2');
           ImageWriterService.flash('foo.img', '/dev/disk2');
           $rootScope.$apply();
@@ -149,6 +178,8 @@ describe('Browser: ImageWriter', function() {
         });
 
         it('should be rejected with the error', function() {
+          ImageWriterService.setFlashing(false);
+
           let rejection;
           ImageWriterService.flash('foo.img', '/dev/disk2').catch(function(error) {
             rejection = error;