More defensive 'of many' logic (#461)

Author: calbach

ui/src/app/shared/header/header.component.spec.ts

@@ -39,7 +39,7 @@ describe('HeaderComponent', () => {
 
   const initJobs: JobListView = {
     results: [testJob1, testJob2, testJob3],
-    totalSize: null,
+    totalSize: undefined,
     exhaustive: false,
     stale: false
   };
@@ -139,7 +139,7 @@ describe('HeaderComponent', () => {
     testComponent.chips.delete('statuses');
     testComponent.jobs.next({
       results: [testJob1, testJob2],
-      totalSize: null,
+      totalSize: undefined,
       exhaustive: true,
       stale: false
     });
@@ -156,7 +156,7 @@ describe('HeaderComponent', () => {
     testComponent.chips.delete('statuses');
     testComponent.jobs.next({
       results: [testJob1, testJob2],
-      totalSize: null,
+      totalSize: undefined,
       exhaustive: false,
       stale: false
     });
@@ -172,7 +172,7 @@ describe('HeaderComponent', () => {
   it('should not show length of inexhaustive job streams of unknown length', async(() => {
     testComponent.jobs.next({
       results: [testJob1],
-      totalSize: null,
+      totalSize: undefined,
       exhaustive: false,
       stale: false
     });
@@ -184,7 +184,7 @@ describe('HeaderComponent', () => {
     // Transition to exhaustive, "of X" should now display length (even though totalSize is still null).
     testComponent.jobs.next({
       results: [testJob1, testJob2],
-      totalSize: null,
+      totalSize: undefined,
       exhaustive: true,
       stale: false
     });

ui/src/app/shared/header/header.component.ts

@@ -281,8 +281,8 @@ export class JobsPaginatorIntl extends MatPaginatorIntl {
   getRangeLabel = (page: number, pageSize: number, length: number) => {
 
     let knownLength = null;
-
-    if (this.backendJobs.value.totalSize !== null) {
+    if (this.backendJobs.value.totalSize ||
+        this.backendJobs.value.totalSize === 0) {
       knownLength = this.backendJobs.value.totalSize;
     } else if (this.backendJobs.value.exhaustive) {
       knownLength = length;

ui/src/app/shared/job-stream.ts

@@ -19,7 +19,7 @@ export class JobStream extends BehaviorSubject<JobListView> {
               private request: QueryJobsRequest) {
     super({
       results: [],
-      totalSize: 0,
+      totalSize: undefined,
       exhaustive: false,
       stale: false
     });
@@ -72,7 +72,7 @@ export class JobStream extends BehaviorSubject<JobListView> {
 // by the exhaustive flag.
 export type JobListView = {
   results: QueryJobsResult[];
-  totalSize: number|null;
+  totalSize: number|undefined;
   exhaustive: boolean;
   stale: boolean;
 }