Show indication when no labels are found (#183)

Show indication when no labels are found

Previously, when no labels are found, there was no indication.

Let's
* Show an indication when no labels match the input
* Show an indication when the repository has no labels

src/app/shared/filter-bar/label-filter-bar/label-filter-bar.component.css

@@ -123,3 +123,9 @@
 mat-list-option {
   width: max-content;
 }
+
+.no-labels {
+  /* Chosen to look similar to button above. */
+  padding: 0 16px;
+  font-size: 14px;
+}

src/app/shared/filter-bar/label-filter-bar/label-filter-bar.component.html

@@ -15,6 +15,7 @@
 
     <button mat-button (click)="removeAllSelection()">Remove all</button>
 
+    <div *ngIf="!hasLabels(input.value)" class="no-labels">No Labels Found!</div>
     <div class="scroll-container-wrapper">
       <div class="scroll-container">
         <mat-selection-list [(ngModel)]="selectedLabelNames" (selectionChange)="updateSelection()">

src/app/shared/filter-bar/label-filter-bar/label-filter-bar.component.ts

@@ -95,6 +95,13 @@ export class LabelFilterBarComponent implements OnInit, OnDestroy {
     return !target.toLowerCase().includes(filter.toLowerCase());
   }
 
+  hasLabels(filter: string): boolean {
+    if (this.allLabels === undefined || this.allLabels.length === 0) {
+      return false;
+    }
+    return this.allLabels.some((label) => !this.filter(filter, label.name));
+  }
+
   updateSelection(): void {
     this.selectedLabels.next(this.selectedLabelNames);
   }