fix time regions using zero hours

public/app/plugins/panel/graph/specs/time_region_manager.test.ts

@@ -130,6 +130,33 @@ describe('TimeRegionManager', () => {
       });
     });
 
+    plotOptionsScenario('for time from/to region', ctx => {
+      const regions = [{ from: '00:00', to: '05:00', fill: true, colorMode: 'red' }];
+      const from = moment('2018-12-01T00:00+01:00');
+      const to = moment('2018-12-03T23:59+01:00');
+      ctx.setup(regions, from, to);
+
+      it('should add 3 markings', () => {
+        expect(ctx.options.grid.markings.length).toBe(3);
+      });
+
+      it('should add one fill between 00:00 and 05:00 each day', () => {
+        const markings = ctx.options.grid.markings;
+
+        expect(moment(markings[0].xaxis.from).format()).toBe(moment('2018-12-01T01:00:00+01:00').format());
+        expect(moment(markings[0].xaxis.to).format()).toBe(moment('2018-12-01T06:00:00+01:00').format());
+        expect(markings[0].color).toBe(colorModes.red.color.fill);
+
+        expect(moment(markings[1].xaxis.from).format()).toBe(moment('2018-12-02T01:00:00+01:00').format());
+        expect(moment(markings[1].xaxis.to).format()).toBe(moment('2018-12-02T06:00:00+01:00').format());
+        expect(markings[1].color).toBe(colorModes.red.color.fill);
+
+        expect(moment(markings[2].xaxis.from).format()).toBe(moment('2018-12-03T01:00:00+01:00').format());
+        expect(moment(markings[2].xaxis.to).format()).toBe(moment('2018-12-03T06:00:00+01:00').format());
+        expect(markings[2].color).toBe(colorModes.red.color.fill);
+      });
+    });
+
     plotOptionsScenario('for day of week from/to region', ctx => {
       const regions = [{ fromDayOfWeek: 7, toDayOfWeek: 7, fill: true, colorMode: 'red' }];
       const from = moment('2018-01-01T18:45:05+01:00');

public/app/plugins/panel/graph/time_region_manager.ts

@@ -87,6 +87,14 @@ export class TimeRegionManager {
         continue;
       }
 
+      if (timeRegion.from && !timeRegion.to) {
+        timeRegion.to = timeRegion.from;
+      }
+
+      if (!timeRegion.from && timeRegion.to) {
+        timeRegion.from = timeRegion.to;
+      }
+
       hRange = {
         from: this.parseTimeRange(timeRegion.from),
         to: this.parseTimeRange(timeRegion.to),
@@ -108,21 +116,13 @@ export class TimeRegionManager {
         hRange.to.dayOfWeek = Number(timeRegion.toDayOfWeek);
       }
 
-      if (!hRange.from.h && hRange.to.h) {
-        hRange.from = hRange.to;
-      }
-
-      if (hRange.from.h && !hRange.to.h) {
-        hRange.to = hRange.from;
-      }
-
-      if (hRange.from.dayOfWeek && !hRange.from.h && !hRange.from.m) {
+      if (hRange.from.dayOfWeek && hRange.from.h === null && hRange.from.m === null) {
         hRange.from.h = 0;
         hRange.from.m = 0;
         hRange.from.s = 0;
       }
 
-      if (hRange.to.dayOfWeek && !hRange.to.h && !hRange.to.m) {
+      if (hRange.to.dayOfWeek && hRange.to.h === null && hRange.to.m === null) {
         hRange.to.h = 23;
         hRange.to.m = 59;
         hRange.to.s = 59;