fix(cdk/accordion): allow for closeAll to be used when multiple mode is disabled (#22055)

Currently `CdkAccordion.closeAll` only works if `multi` is set to false, however it makes
sense when a single item is expanded as well.

These changes also fix that `_openCloseAllActions` wasn't being completed and they
include more unit tests.

Fixes #22003.

(cherry picked from commit a41fb6e)

Author: crisbeto

src/cdk/accordion/accordion.spec.ts

@@ -1,8 +1,10 @@
 import {waitForAsync, TestBed} from '@angular/core/testing';
-import {Component, ViewChild} from '@angular/core';
+import {Component, QueryList, ViewChild, ViewChildren} from '@angular/core';
 import {By} from '@angular/platform-browser';
 import {BrowserAnimationsModule} from '@angular/platform-browser/animations';
-import {CdkAccordionModule, CdkAccordionItem} from './public-api';
+import {CdkAccordion} from './accordion';
+import {CdkAccordionItem} from './accordion-item';
+import {CdkAccordionModule} from './accordion-module';
 
 describe('CdkAccordion', () => {
   beforeEach(waitForAsync(() => {
@@ -59,6 +61,61 @@ describe('CdkAccordion', () => {
 
     expect(innerItem.accordion).not.toBe(outerItem.accordion);
   });
+
+  it('should be able to expand and collapse all items in multiple mode', () => {
+    const fixture = TestBed.createComponent(SetOfItems);
+    fixture.componentInstance.multi = true;
+    fixture.detectChanges();
+    fixture.componentInstance.accordion.openAll();
+    fixture.detectChanges();
+
+    expect(fixture.componentInstance.items.toArray().every(item => item.expanded)).toBe(true);
+
+    fixture.componentInstance.accordion.closeAll();
+    fixture.detectChanges();
+
+    expect(fixture.componentInstance.items.toArray().some(item => item.expanded)).toBe(false);
+  });
+
+  it('should not be able to expand all items if multiple mode is off', () => {
+    const fixture = TestBed.createComponent(SetOfItems);
+    fixture.componentInstance.multi = false;
+    fixture.detectChanges();
+    fixture.componentInstance.accordion.openAll();
+    fixture.detectChanges();
+
+    expect(fixture.componentInstance.items.toArray().some(item => item.expanded)).toBe(false);
+  });
+
+  it('should be able to use closeAll even if multiple mode is disabled', () => {
+    const fixture = TestBed.createComponent(SetOfItems);
+    fixture.componentInstance.multi = false;
+    fixture.detectChanges();
+    const item = fixture.componentInstance.items.first;
+
+    item.expanded = true;
+    fixture.detectChanges();
+
+    fixture.componentInstance.accordion.closeAll();
+    fixture.detectChanges();
+
+    expect(item.expanded).toBe(false);
+  });
+
+  it('should complete the accordion observables on destroy', () => {
+    const fixture = TestBed.createComponent(SetOfItems);
+    fixture.detectChanges();
+    const stateSpy = jasmine.createSpy('stateChanges complete spy');
+    const openCloseSpy = jasmine.createSpy('openCloseAllActions complete spy');
+
+    fixture.componentInstance.accordion._stateChanges.subscribe({complete: stateSpy});
+    fixture.componentInstance.accordion._openCloseAllActions.subscribe({complete: openCloseSpy});
+    fixture.destroy();
+
+    expect(stateSpy).toHaveBeenCalled();
+    expect(openCloseSpy).toHaveBeenCalled();
+  });
+
 });
 
 @Component({template: `
@@ -67,6 +124,8 @@ describe('CdkAccordion', () => {
     <cdk-accordion-item></cdk-accordion-item>
   </cdk-accordion>`})
 class SetOfItems {
+  @ViewChild(CdkAccordion) accordion: CdkAccordion;
+  @ViewChildren(CdkAccordionItem) items: QueryList<CdkAccordionItem>;
   multi: boolean = false;
 }
 

src/cdk/accordion/accordion.ts

@@ -46,12 +46,14 @@ export class CdkAccordion implements OnDestroy, OnChanges {
 
   /** Opens all enabled accordion items in an accordion where multi is enabled. */
   openAll(): void {
-    this._openCloseAll(true);
+    if (this._multi) {
+      this._openCloseAllActions.next(true);
+    }
   }
 
   /** Closes all enabled accordion items in an accordion where multi is enabled. */
   closeAll(): void {
-    this._openCloseAll(false);
+    this._openCloseAllActions.next(false);
   }
 
   ngOnChanges(changes: SimpleChanges) {
@@ -60,12 +62,7 @@ export class CdkAccordion implements OnDestroy, OnChanges {
 
   ngOnDestroy() {
     this._stateChanges.complete();
-  }
-
-  private _openCloseAll(expanded: boolean): void {
-    if (this.multi) {
-      this._openCloseAllActions.next(expanded);
-    }
+    this._openCloseAllActions.complete();
   }
 
   static ngAcceptInputType_multi: BooleanInput;