fix: check if report result exists before formatting

frappe/public/js/frappe/widgets/chart_widget.js

@@ -573,14 +573,17 @@ export default class ChartWidget extends Widget {
 				xIsSeries: this.chart_doc.timeseries,
 				shortenYAxisNumbers: 1
 			},
-			tooltipOptions: {
+		};
+
+		if (this.report_result && this.report_result.chart) {
+			chart_args.tooltipOptions = {
 				formatTooltipY: value =>
 					frappe.format(value, {
 						fieldtype: this.report_result.chart.fieldtype,
 						options: this.report_result.chart.options
 					}, { always_show_decimals: true, inline: true })
 			}
-		};
+		}
 
 		if (this.chart_doc.type == "Heatmap") {
 			const heatmap_year = parseInt(this.selected_heatmap_year || this.chart_settings.heatmap_year || this.chart_doc.heatmap_year);