working on overview panel and unit tests

src/app/panels/overview/module.js

@@ -37,7 +37,9 @@ function (angular, app, _) {
     $scope.init = function() {
       panelSrv.init(this);
 
-      $scope.get_data();
+      if (!$scope.skipDataOnInit) {
+        $scope.get_data();
+      }
       //$scope.$on('refresh', $scope.render);
       //$scope.render();
     };

src/test/specs/overview-ctrl-specs.js

@@ -3,46 +3,60 @@ define([
 ], function() {
   'use strict';
 
+  function ControllerTestContext() {
+    var self = this;
+
+    this.datasource = {};
+    this.datasourceSrv = {
+      getMetricSources: function() {},
+      get: function() { return self.datasource; }
+    };
+
+    this.providePhase = function() {
+      return module(function($provide) {
+        $provide.value('datasourceSrv', self.datasourceSrv);
+      });
+    };
+
+    this.createControllerPhase = function(controllerName) {
+      return inject(function($controller, $rootScope, $q) {
+        self.scope = $rootScope.$new();
+        self.scope.panel = {};
+        self.scope.filter = {
+          timeRange: function() {}
+        };
+
+        self.$q = $q;
+        self.scope.skipDataOnInit = true;
+        self.controller = $controller(controllerName, {
+          $scope: self.scope
+        });
+
+      });
+    };
+
+  }
+
   describe('OverviewCtrl', function() {
-    var _controller;
-    var _scope;
-    var _datasource;
+    var ctx = new ControllerTestContext();
 
     beforeEach(module('grafana.services'));
     beforeEach(module('grafana.panels.overview'));
 
-    beforeEach(module(function($provide){
-      $provide.value('datasourceSrv',{
-        getMetricSources: function() {
-        },
-        get: function() {
-          return _datasource;
-        }
-      });
-    }));
-
-    beforeEach(inject(function($controller, $rootScope, $q) {
-      _scope = $rootScope.$new();
-      _scope.panel = { targets: [] };
-      _scope.filter = {
-        timeRange: function() { }
-      };
-      _scope.datasource = {
-        query: function() {
-          return $q.resolve('hej');
-        }
-      };
-      _controller = $controller('OverviewCtrl', {
-        $scope: _scope
-      });
-    }));
+    beforeEach(ctx.providePhase());
+    beforeEach(ctx.createControllerPhase('OverviewCtrl'));
 
-    describe('init', function() {
+    describe('when query return error', function() {
       beforeEach(function() {
+        ctx.datasource.query =  function() {
+          return ctx.$q.reject({ message: 'Some error' });
+        };
+        ctx.scope.get_data();
+        ctx.scope.$digest();
       });
 
-      it('description', function() {
-
+      it('panel.error should be set', function() {
+        expect(ctx.scope.panel.error).to.be("Some error");
       });
     });
   });