hotfix: support empty series

src/index.ts

@@ -10,7 +10,7 @@ import { setBarScaleY, setBarScaleX } from './models/bar_state';
 import {
   BarSerie, BarOptions, DiscreteConfig, NonDiscreteConfig,
   BarPodType, SizeType, CallbackEvent, Color, Opacity,
-  ColorFormatter, OpacityFormatter,
+  BarData, ColorFormatter, OpacityFormatter,
   Datapoint, ValueX, ValueY,
 } from './types';
 
@@ -108,9 +108,19 @@ export class ChartwerkBarPod extends ChartwerkPod<BarSerie, BarOptions> {
     if(!this.series.isSeriesAvailable) {
       return undefined;
     }
-    const mousePoisitionKey = Math.ceil(this.state.xScale.invert(eventX));
+    const mousePositionKey = this.state.xScale.invert(eventX);
     const keys = _.map(this.dataProcessor.dataRows, (dataRow: DataRow) => dataRow.key);
-    const idx = findClosest(keys, mousePoisitionKey);
+    let idx: number;
+    switch(this.options.barType) {
+      case BarPodType.DISCRETE:
+        idx = Math.floor(mousePositionKey);
+        break;
+      case BarPodType.NON_DISCRETE:
+        idx = findClosest(keys, mousePositionKey);
+        break;
+      default:
+        break;
+    }
     return this.dataProcessor.dataRows[idx];
   }
 
@@ -152,6 +162,6 @@ export {
   BarSerie, BarOptions, TimeFormat, AxisFormat,
   DiscreteConfig, NonDiscreteConfig,
   BarPodType, SizeType, CallbackEvent, Color, Opacity,
-  ColorFormatter, OpacityFormatter,
+  BarData, ColorFormatter, OpacityFormatter,
   Datapoint, ValueX, ValueY, DataItem, DataRow,
 };

src/models/bar_state.ts

@@ -13,14 +13,24 @@ export function setBarScaleX(state: PodState<BarSerie, BarOptions>, dataRows: Da
   switch(options.barType) {
     case BarPodType.DISCRETE:
       const config: DiscreteConfig = options.dicreteConfig;
-      const discreteStep = _.isNumber(config.step) ? config.step : (_.last(dataRows).key - _.first(dataRows).key) / dataRows.length;
+      let discreteStep = 0;
+      if(_.isNumber(config.step)) {
+        discreteStep = config.step;
+      } else {
+        if(!_.isEmpty(dataRows)) {
+          discreteStep = (_.last(dataRows).key - _.first(dataRows).key) / dataRows.length;
+        }
+      }
       state.xValueRange = [state.xValueRange[0], state.xValueRange[1] + discreteStep];
       return;
     case BarPodType.NON_DISCRETE:
       if(!_.isEmpty(options.axis.x.range)) {
         return;
       }
-      const nonDiscreteStep = (_.last(dataRows).key - _.first(dataRows).key) / dataRows.length;
+      let nonDiscreteStep = 0;
+      if(!_.isEmpty(dataRows)) {
+        nonDiscreteStep = (_.last(dataRows).key - _.first(dataRows).key) / dataRows.length;
+      }
       state.xValueRange = [state.xValueRange[0], state.xValueRange[1] + nonDiscreteStep];
       return;
   }

src/models/data_processor.ts

@@ -113,7 +113,7 @@ export class DataProcessor {
     if(_.isFunction(opacity)) {
       return _.map(values, (value, i) => (opacity as Function)({ value, barIndex: i, key, target }));
     }
-    throw new Error(`Unknown type of serie opacity: ${target} ${opacity}`); 
+    throw new Error(`Unknown type of serie opacity: ${target} ${opacity}`);
   }
 
   getMaxSumm(values: number[]): number {
@@ -128,6 +128,10 @@ export class DataProcessor {
     if(this.options.barType === BarPodType.NON_DISCRETE) {
       return;
     }
+    // TODO: move non-empty datapoints validation to core
+    if(_.isEmpty(this.visibleSeries)) {
+      return;
+    }
     const xValuesList = _.map(_.first(this.visibleSeries).datapoints, dp => dp[0]);
     _.forEach(this.visibleSeries, serie => {
       const serieXList = _.map(serie.datapoints, dp => dp[0]);

src/types.ts

@@ -4,8 +4,9 @@ import { DataRow } from 'models/data_processor';
 export type ValueX = (number | string);
 export type ValueY = number;
 export type Datapoint = [ValueX, ...ValueY[]]; // [x, y, y, y, ..., y], multiple y values as stacked bars
-export type ColorFormatter = (data: { value: ValueY, key: ValueX, barIndex: number, target: string }) => string;
-export type OpacityFormatter = (data: { value: ValueY, key: ValueX, barIndex: number, target: string }) => number;
+export type BarData = { value: ValueY, key: ValueX, barIndex: number, target: string };
+export type ColorFormatter = (data: BarData) => string;
+export type OpacityFormatter = (data: BarData) => number;
 export type Color = string | string[] | ColorFormatter;
 export type Opacity = number | number[] | OpacityFormatter;