refactor: clean up removeChild usages

Now that we don't have to support IE11 anymore, we can use `Element.remove` instead of `removeChild`.

Author: crisbeto

src/cdk-experimental/column-resize/resizable.ts

@@ -108,14 +108,8 @@ export abstract class Resizable<HandleComponent extends ResizeOverlayHandle>
   ngOnDestroy(): void {
     this.destroyed.next();
     this.destroyed.complete();
-
-    if (this.inlineHandle) {
-      this.elementRef.nativeElement!.removeChild(this.inlineHandle);
-    }
-
-    if (this.overlayRef) {
-      this.overlayRef.dispose();
-    }
+    this.inlineHandle?.remove();
+    this.overlayRef?.dispose();
   }
 
   protected abstract getInlineHandleCssClassName(): string;

src/cdk-experimental/column-resize/resize-strategy.ts

@@ -178,11 +178,8 @@ export class CdkFlexTableResizeStrategy extends ResizeStrategy implements OnDest
   }
 
   ngOnDestroy(): void {
-    // TODO: Use remove() once we're off IE11.
-    if (this._styleElement && this._styleElement.parentNode) {
-      this._styleElement.parentNode.removeChild(this._styleElement);
-      this._styleElement = undefined;
-    }
+    this._styleElement?.remove();
+    this._styleElement = undefined;
   }
 
   private _getPropertyValue(cssFriendlyColumnName: string, key: string): string|undefined {

src/cdk-experimental/dialog/dialog.spec.ts

@@ -877,7 +877,7 @@ describe('Dialog', () => {
   describe('focus management', () => {
     // When testing focus, all of the elements must be in the DOM.
     beforeEach(() => document.body.appendChild(overlayContainerElement));
-    afterEach(() => document.body.removeChild(overlayContainerElement));
+    afterEach(() => overlayContainerElement.remove());
 
     it('should focus the first tabbable element of the dialog on open (the default)',
       fakeAsync(() => {
@@ -971,7 +971,7 @@ describe('Dialog', () => {
         .withContext('Expected that the trigger was refocused after the dialog is closed.')
         .toBe('dialog-trigger');
 
-      document.body.removeChild(button);
+      button.remove();
     }));
 
     it('should re-focus trigger element inside the shadow DOM when dialog closes', fakeAsync(() => {
@@ -1036,8 +1036,8 @@ describe('Dialog', () => {
       expect(document.activeElement!.id)
         .withContext('Expected focus to stay on the alternate button.').toBe('other-button');
 
-      body.removeChild(button);
-      body.removeChild(otherButton);
+      button.remove();
+      otherButton.remove();
     }));
 
     it('should allow the consumer to shift focus in afterClosed', fakeAsync(() => {
@@ -1069,8 +1069,8 @@ describe('Dialog', () => {
         .withContext('Expected that the trigger was refocused after the dialog is closed.')
         .toBe('input-to-be-focused');
 
-      document.body.removeChild(button);
-      document.body.removeChild(input);
+      button.remove();
+      input.remove();
       flush();
     }));
 

src/cdk-experimental/listbox/listbox.ts

@@ -174,7 +174,7 @@ export class CdkOption<T = unknown> implements ListKeyManagerOption, Highlightab
   private _removeIcons(element: Element) {
     // TODO: make this a configurable function that can removed any desired type of node.
     for (const icon of Array.from(element.querySelectorAll('mat-icon, .material-icons'))) {
-      icon.parentNode?.removeChild(icon);
+      icon.remove();
     }
   }
 

src/cdk-experimental/menu/menu-item.ts

@@ -35,7 +35,7 @@ import {Toggler, MENU_AIM, MenuAim} from './menu-aim';
 /** Removes all icons from within the given element. */
 function removeIcons(element: Element) {
   for (const icon of Array.from(element.querySelectorAll('mat-icon, .material-icons'))) {
-    icon.parentNode?.removeChild(icon);
+    icon.remove();
   }
 }
 

src/cdk-experimental/table-scroll-container/table-scroll-container.ts

@@ -67,11 +67,8 @@ export class CdkTableScrollContainer implements StickyPositioningListener,
   }
 
   ngOnDestroy(): void {
-    // TODO: Use remove() once we're off IE11.
-    if (this._styleElement?.parentNode) {
-      this._styleElement.parentNode.removeChild(this._styleElement);
-      this._styleElement = undefined;
-    }
+    this._styleElement?.remove();
+    this._styleElement = undefined;
   }
 
   stickyColumnsUpdated({sizes}: StickyUpdate): void {

src/cdk/a11y/aria-describer/aria-describer.spec.ts

@@ -214,10 +214,7 @@ describe('AriaDescriber', () => {
 
     // Use `querySelectorAll` with an attribute since `getElementById` will stop at the first match.
     expect(document.querySelectorAll(`[id='${MESSAGES_CONTAINER_ID}']`).length).toBe(1);
-
-    if (extraContainer.parentNode) {
-      extraContainer.parentNode.removeChild(extraContainer);
-    }
+    extraContainer.remove();
   });
 
   it('should not describe messages that match up with the aria-label of the element', () => {

src/cdk/a11y/aria-describer/aria-describer.ts

@@ -156,10 +156,7 @@ export class AriaDescriber implements OnDestroy {
   /** Deletes the message element from the global messages container. */
   private _deleteMessageElement(key: string|Element) {
     const registeredMessage = messageRegistry.get(key);
-    const messageElement = registeredMessage && registeredMessage.messageElement;
-    if (messagesContainer && messageElement) {
-      messagesContainer.removeChild(messageElement);
-    }
+    registeredMessage?.messageElement?.remove();
     messageRegistry.delete(key);
   }
 
@@ -172,9 +169,7 @@ export class AriaDescriber implements OnDestroy {
       // already a container on the page, but we don't have a reference to it. Clear the
       // old container so we don't get duplicates. Doing this, instead of emptying the previous
       // container, should be slightly faster.
-      if (preExistingContainer && preExistingContainer.parentNode) {
-        preExistingContainer.parentNode.removeChild(preExistingContainer);
-      }
+      preExistingContainer?.remove();
 
       messagesContainer = this._document.createElement('div');
       messagesContainer.id = MESSAGES_CONTAINER_ID;
@@ -193,8 +188,8 @@ export class AriaDescriber implements OnDestroy {
 
   /** Deletes the global messages container. */
   private _deleteMessagesContainer() {
-    if (messagesContainer && messagesContainer.parentNode) {
-      messagesContainer.parentNode.removeChild(messagesContainer);
+    if (messagesContainer) {
+      messagesContainer.remove();
       messagesContainer = null;
     }
   }

src/cdk/a11y/aria-describer/aria-reference.spec.ts

@@ -9,7 +9,7 @@ describe('AriaReference', () => {
   });
 
   afterEach(() => {
-    document.body.removeChild(testElement!);
+    testElement?.remove();
   });
 
   it('should be able to append/remove aria reference IDs', () => {

src/cdk/a11y/focus-trap/focus-trap.ts

@@ -76,18 +76,12 @@ export class FocusTrap {
 
     if (startAnchor) {
       startAnchor.removeEventListener('focus', this.startAnchorListener);
-
-      if (startAnchor.parentNode) {
-        startAnchor.parentNode.removeChild(startAnchor);
-      }
+      startAnchor.remove();
     }
 
     if (endAnchor) {
       endAnchor.removeEventListener('focus', this.endAnchorListener);
-
-      if (endAnchor.parentNode) {
-        endAnchor.parentNode.removeChild(endAnchor);
-      }
+      endAnchor.remove();
     }
 
     this._startAnchor = this._endAnchor = null;

src/cdk/a11y/high-contrast-mode/high-contrast-mode-detector.ts

@@ -74,7 +74,7 @@ export class HighContrastModeDetector {
         documentWindow.getComputedStyle(testElement) : null;
     const computedColor =
         (computedStyle && computedStyle.backgroundColor || '').replace(/ /g, '');
-    this._document.body.removeChild(testElement);
+    testElement.remove();
 
     switch (computedColor) {
       case 'rgb(0,0,0)': return HighContrastMode.WHITE_ON_BLACK;

src/cdk/a11y/interactivity-checker/interactivity-checker.spec.ts

@@ -16,7 +16,7 @@ describe('InteractivityChecker', () => {
   }));
 
   afterEach(() => {
-    document.body.removeChild(testContainerElement);
+    testContainerElement.remove();
     testContainerElement.innerHTML = '';
   });
 
@@ -529,8 +529,7 @@ describe('InteractivityChecker', () => {
     tmpRoot.innerHTML = template;
 
     const element = tmpRoot.firstElementChild!;
-
-    tmpRoot.removeChild(element);
+    element.remove();
 
     if (append) {
       appendElements([element]);

src/cdk/a11y/live-announcer/live-announcer.spec.ts

@@ -133,10 +133,7 @@ describe('LiveAnnouncer', () => {
       expect(document.body.querySelectorAll('.cdk-live-announcer-element').length)
         .withContext('Expected only one live announcer element in the DOM.')
         .toBe(1);
-
-      if (extraElement.parentNode) {
-        extraElement.parentNode.removeChild(extraElement);
-      }
+      extraElement.remove();
     }));
 
     it('should clear any previous timers when a new one is started', fakeAsync(() => {

src/cdk/a11y/live-announcer/live-announcer.ts

@@ -143,8 +143,8 @@ export class LiveAnnouncer implements OnDestroy {
   ngOnDestroy() {
     clearTimeout(this._previousTimeout);
 
-    if (this._liveElement && this._liveElement.parentNode) {
-      this._liveElement.parentNode.removeChild(this._liveElement);
+    if (this._liveElement) {
+      this._liveElement.remove();
       this._liveElement = null!;
     }
   }
@@ -156,7 +156,7 @@ export class LiveAnnouncer implements OnDestroy {
 
     // Remove any old containers. This can happen when coming in from a server-side-rendered page.
     for (let i = 0; i < previousElements.length; i++) {
-      previousElements[i].parentNode!.removeChild(previousElements[i]);
+      previousElements[i].remove();
     }
 
     liveEl.classList.add(elementClass);

src/cdk/clipboard/clipboard.spec.ts

@@ -28,9 +28,7 @@ describe('Clipboard', () => {
   });
 
   afterEach(() => {
-    if (focusedInput.parentNode) {
-      focusedInput.parentNode.removeChild(focusedInput);
-    }
+    focusedInput.remove();
   });
 
   describe('#beginCopy', () => {
@@ -79,8 +77,7 @@ describe('Clipboard', () => {
 
       clipboard.copy(COPY_CONTENT);
       expect(document.activeElement).toBe(svg);
-
-      svg.parentNode!.removeChild(svg);
+      svg.remove();
     });
 
     describe('when execCommand fails', () => {

src/cdk/clipboard/pending-copy.ts

@@ -67,10 +67,7 @@ export class PendingCopy {
     const textarea = this._textarea;
 
     if (textarea) {
-      if (textarea.parentNode) {
-        textarea.parentNode.removeChild(textarea);
-      }
-
+      textarea.remove();
       this._textarea = undefined;
     }
   }

src/cdk/drag-drop/directives/drag.spec.ts

@@ -2300,7 +2300,7 @@ expect(item.style.top)
         const preview = document.querySelector('.cdk-drag-preview')! as HTMLElement;
 
         expect(preview.parentNode).toBe(fakeDocument.fullscreenElement);
-        fakeDocument.fullscreenElement.parentNode!.removeChild(fakeDocument.fullscreenElement);
+        fakeDocument.fullscreenElement.remove();
       }));
 
     it('should be able to constrain the preview position', fakeAsync(() => {
@@ -5795,7 +5795,7 @@ expect(sourceCanvas.getContext('2d')!
           targetRect.left + 1, targetRect.top + 1);
 
         // Remove the extra node after the element was dropped, but before the animation is over.
-        extraSibling.parentNode!.removeChild(extraSibling);
+        extraSibling.remove();
 
         expect(() => {
           flush();
@@ -7235,7 +7235,7 @@ function makeScrollable(
 
   return () => {
     scrollTo(0, 0);
-    veryTallElement.parentNode!.removeChild(veryTallElement);
+    veryTallElement.remove();
   };
 }
 

src/cdk/drag-drop/drag-ref.ts

@@ -485,10 +485,10 @@ export class DragRef<T = any> {
     if (this.isDragging()) {
       // Since we move out the element to the end of the body while it's being
       // dragged, we have to make sure that it's removed if it gets destroyed.
-      removeNode(this._rootElement);
+      this._rootElement?.remove();
     }
 
-    removeNode(this._anchor);
+    this._anchor?.remove();
     this._destroyPreview();
     this._destroyPlaceholder();
     this._dragDropRegistry.removeDragItem(this);
@@ -606,27 +606,15 @@ export class DragRef<T = any> {
 
   /** Destroys the preview element and its ViewRef. */
   private _destroyPreview() {
-    if (this._preview) {
-      removeNode(this._preview);
-    }
-
-    if (this._previewRef) {
-      this._previewRef.destroy();
-    }
-
+    this._preview?.remove();
+    this._previewRef?.destroy();
     this._preview = this._previewRef = null!;
   }
 
   /** Destroys the placeholder element and its ViewRef. */
   private _destroyPlaceholder() {
-    if (this._placeholder) {
-      removeNode(this._placeholder);
-    }
-
-    if (this._placeholderRef) {
-      this._placeholderRef.destroy();
-    }
-
+    this._placeholder?.remove();
+    this._placeholderRef?.destroy();
     this._placeholder = this._placeholderRef = null!;
   }
 
@@ -1480,16 +1468,6 @@ function clamp(value: number, min: number, max: number) {
   return Math.max(min, Math.min(max, value));
 }
 
-/**
- * Helper to remove a node from the DOM and to do all the necessary null checks.
- * @param node Node to be removed.
- */
-function removeNode(node: Node | null) {
-  if (node && node.parentNode) {
-    node.parentNode.removeChild(node);
-  }
-}
-
 /** Determines whether an event is a touch event. */
 function isTouchEvent(event: MouseEvent | TouchEvent): event is TouchEvent {
   // This function is called for every pixel that the user has dragged so we need it to be

src/cdk/overlay/dispatchers/overlay-keyboard-dispatcher.spec.ts

@@ -80,8 +80,7 @@ describe('OverlayKeyboardDispatcher', () => {
     dispatchKeyboardEvent(button, 'keydown', ESCAPE);
 
     expect(spy).not.toHaveBeenCalled();
-
-    button.parentNode!.removeChild(button);
+    button.remove();
   });
 
   it('should complete the keydown stream on dispose', () => {