Move timestamp comparator function into shared util module.

web/src/components/measure-details/simple-details.ts

@@ -4,6 +4,7 @@ import moment from 'moment';
 import assign from 'lodash.assign';
 import { library } from '@fortawesome/fontawesome-svg-core';
 import { faPencilAlt } from '@fortawesome/free-solid-svg-icons';
+import { byTimestampComparator } from '@/util';
 
 library.add(faPencilAlt);
 
@@ -28,7 +29,7 @@ export class SimpleDetails extends Vue {
     return [{
       name: this.measure.name,
       data: measurementData
-        .sort((a, b) => a.timestamp.getTime() - b.timestamp.getTime())
+        .sort(byTimestampComparator)
         .map((m) => ({ x: m.timestamp.toISOString(), y: m.value }))
     }];
   }

web/src/util.ts

@@ -0,0 +1,7 @@
+import { Measurement, MeasurementMeta } from '@/models';
+
+export function byTimestampComparator<T extends MeasurementMeta>(
+  a: Measurement<T>,
+  b: Measurement<T>): number {
+  return a.timestamp.getTime() - b.timestamp.getTime();
+}