Fixes for PowerBi tests (#51)

* handle null column

* override state errors during load

* logo color

* use language file

* whitespace

packages/powerbi/src/app.ts

@@ -16,6 +16,7 @@ import {
     util
 } from '@msrvida/sanddance-explorer';
 import { Logo } from '@msrvida/sanddance-explorer/dist/es6/controls/logo';
+import { strings } from './language';
 
 fabric.initializeIcons();
 
@@ -32,7 +33,7 @@ export interface Props {
 }
 
 export interface State {
-    loaded: boolean
+    loaded: boolean;
     chromeless: boolean;
     darkTheme: boolean;
 }
@@ -124,7 +125,7 @@ export class App extends React.Component<Props, State> {
             React.createElement("div", { className: "sanddance-init" },
                 React.createElement("div", null,
                     React.createElement(Logo),
-                    React.createElement("div", null, "Please add fields to Values") //TODO language
+                    React.createElement("div", null, strings.notLoaded)
                 )
             )
         );

packages/powerbi/src/language.ts

@@ -0,0 +1,5 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT license.
+export const strings = {    
+    notLoaded: "Please add fields to Values"
+}

packages/powerbi/src/visual.ts

@@ -107,6 +107,7 @@ export class Visual implements IVisual {
         }
 
         this.app.load(data, columns => {
+            if (!columns) return;
 
             const {
                 sandDanceMainSettings,

packages/powerbi/style/visual.less

@@ -37,7 +37,7 @@
       text-align: center;
     }
     svg {
-      fill: red;
+      fill: rgb(0, 120, 212);
       height: 50px;
     }
   }

packages/sanddance-explorer/src/columns.ts

@@ -14,13 +14,13 @@ export function ensureColumnsExist(insightColumns: SandDance.types.InsightColumn
 
 export function ensureColumnsPopulated(chart: SandDance.types.Chart, insightColumns: SandDance.types.InsightColumns, actualColumns: SandDance.types.Column[]) {
     //ensure columns are populated
-    const firstColumnName = actualColumns[0].name;
+    const firstColumn = actualColumns[0];
+    const firstColumnName = firstColumn && firstColumn.name;
     const ensureColumn = (role: SandDance.types.InsightColumnRoles) => {
         if (!insightColumns[role]) {
             insightColumns[role] = firstColumnName;
         }
     };
-
     switch (chart) {
         case 'barchart':
             ensureColumn('x');

packages/sanddance-explorer/src/explorer.tsx

@@ -289,9 +289,7 @@ export class Explorer extends React.Component<Props, State> {
 
         ensureColumnsExist(newState.columns, dataContent.columns);
         const errors = ensureColumnsPopulated(partialInsight ? partialInsight.chart : null, newState.columns, dataContent.columns);
-        if (errors) {
-          newState.errors = errors;
-        }
+        newState.errors = errors;
 
         this.changeInsight(newState as State);
         //make sure item is active

packages/sanddance/src/specs/inference.ts

@@ -12,7 +12,8 @@ function isQuantitative(column: Column) {
  * @param data Array of data objects.
  */
 export function getColumnsFromData(data: object[], columnTypes?: ColumnTypeMap) {
-    const fields = Object.keys(data[0]);
+    const sample = data[0];
+    const fields = sample ? Object.keys(sample) : [];
     const inferences = { ...VegaDeckGl.base.vega.inferTypes(data, fields), ...columnTypes };
     const columns = fields.map(name => {
         const column: Column = {