refactor: clean out variables that are being assigned to but not being read

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

@@ -76,12 +76,10 @@ describe('FocusTrap', () => {
 
   describe('with bindings', () => {
     let fixture: ComponentFixture<FocusTrapWithBindings>;
-    let focusTrapInstance: FocusTrap;
 
     beforeEach(() => {
       fixture = TestBed.createComponent(FocusTrapWithBindings);
       fixture.detectChanges();
-      focusTrapInstance = fixture.componentInstance.focusTrapDirective.focusTrap;
     });
 
     it('should clean up its anchor sibling elements on destroy', () => {

src/cdk/layout/media-matcher.spec.ts

@@ -5,13 +5,12 @@
  * Use of this source code is governed by an MIT-style license that can be
  * found in the LICENSE file at https://angular.io/license
  */
-import {LayoutModule, BreakpointObserver} from './index';
+import {LayoutModule} from './index';
 import {MediaMatcher} from './media-matcher';
 import {async, TestBed, inject} from '@angular/core/testing';
 import {Platform} from '@angular/cdk/platform';
 
 describe('MediaMatcher', () => {
-  let breakpointManager: BreakpointObserver;
   let mediaMatcher: MediaMatcher;
 
   beforeEach(async(() => {
@@ -20,12 +19,9 @@ describe('MediaMatcher', () => {
     });
   }));
 
-  beforeEach(inject(
-    [BreakpointObserver, MediaMatcher],
-    (bm: BreakpointObserver, mm: MediaMatcher) => {
-      breakpointManager = bm;
-      mediaMatcher = mm;
-    }));
+  beforeEach(inject([MediaMatcher], (mm: MediaMatcher) => {
+    mediaMatcher = mm;
+  }));
 
   it('correctly returns a MediaQueryList to check for matches', () => {
     expect(mediaMatcher.matchMedia('(min-width: 1px)').matches).toBeTruthy();

src/cdk/overlay/position/connected-position-strategy.ts

@@ -35,9 +35,6 @@ import {OverlayRef} from '../overlay-ref';
  * of the overlay.
  */
 export class ConnectedPositionStrategy implements PositionStrategy {
-  /** The overlay to which this strategy is attached. */
-  private _overlayRef: OverlayRef;
-
   /** Layout direction of the position strategy. */
   private _dir = 'ltr';
 
@@ -100,7 +97,6 @@ export class ConnectedPositionStrategy implements PositionStrategy {
 
   /** Attach this position strategy to an overlay. */
   attach(overlayRef: OverlayRef): void {
-    this._overlayRef = overlayRef;
     this._pane = overlayRef.overlayElement;
     this._resizeSubscription.unsubscribe();
     this._resizeSubscription = this._viewportRuler.change().subscribe(() => this.apply());

src/cdk/tree/tree.ts

@@ -139,9 +139,6 @@ export class CdkTree<T> implements CollectionViewer, OnInit, OnDestroy {
   /** Subject that emits when the component has been destroyed. */
   private _onDestroy = new Subject<void>();
 
-  /** Latest data provided by the data source through the connect interface. */
-  private _data = new Array<T>();
-
   /** Differ used to find the changes in the data provided by the data source. */
   private _dataDiffer: IterableDiffer<T>;
 
@@ -231,8 +228,6 @@ export class CdkTree<T> implements CollectionViewer, OnInit, OnDestroy {
    * clearing the node outlet. Otherwise start listening for new data.
    */
   private _switchDataSource(dataSource: DataSource<T> | Observable<T[]> | T[]) {
-    this._data = new Array<T>();
-
     if (this._dataSource && typeof (this._dataSource as DataSource<T>).disconnect === 'function') {
       (this.dataSource as DataSource<T>).disconnect(this);
     }
@@ -269,10 +264,7 @@ export class CdkTree<T> implements CollectionViewer, OnInit, OnDestroy {
 
     if (dataStream) {
       this._dataSubscription = dataStream.pipe(takeUntil(this._onDestroy))
-        .subscribe(data => {
-          this._data = data;
-          this._renderNodeChanges(data);
-        });
+        .subscribe(data => this._renderNodeChanges(data));
     } else {
       throw getTreeNoValidDataSourceError();
     }

src/lib/autocomplete/autocomplete.spec.ts

@@ -1468,6 +1468,7 @@ describe('MatAutocomplete', () => {
       zone.simulateZoneExit();
 
       expect(spy).toHaveBeenCalledWith(jasmine.any(MatOptionSelectionChange));
+      subscription!.unsubscribe();
     }));
 
   });

src/lib/button-toggle/button-toggle.spec.ts

@@ -81,9 +81,7 @@ describe('MatButtonToggle with forms', () => {
   describe('button toggle group with ngModel and change event', () => {
     let fixture: ComponentFixture<ButtonToggleGroupWithNgModel>;
     let groupDebugElement: DebugElement;
-    let groupNativeElement: HTMLElement;
     let buttonToggleDebugElements: DebugElement[];
-    let buttonToggleNativeElements: HTMLElement[];
     let groupInstance: MatButtonToggleGroup;
     let buttonToggleInstances: MatButtonToggle[];
     let testComponent: ButtonToggleGroupWithNgModel;
@@ -96,13 +94,10 @@ describe('MatButtonToggle with forms', () => {
       testComponent = fixture.debugElement.componentInstance;
 
       groupDebugElement = fixture.debugElement.query(By.directive(MatButtonToggleGroup));
-      groupNativeElement = groupDebugElement.nativeElement;
       groupInstance = groupDebugElement.injector.get<MatButtonToggleGroup>(MatButtonToggleGroup);
       groupNgModel = groupDebugElement.injector.get<NgModel>(NgModel);
 
       buttonToggleDebugElements = fixture.debugElement.queryAll(By.directive(MatButtonToggle));
-      buttonToggleNativeElements =
-        buttonToggleDebugElements.map(debugEl => debugEl.nativeElement);
       buttonToggleInstances = buttonToggleDebugElements.map(debugEl => debugEl.componentInstance);
       buttonToggleLabels = buttonToggleDebugElements.map(
         debugEl => debugEl.query(By.css('label')).nativeElement);
@@ -545,14 +540,11 @@ describe('MatButtonToggle without forms', () => {
     let buttonToggleNativeElement: HTMLElement;
     let buttonToggleLabelElement: HTMLLabelElement;
     let buttonToggleInstance: MatButtonToggle;
-    let testComponent: StandaloneButtonToggle;
 
     beforeEach(async(() => {
       fixture = TestBed.createComponent(StandaloneButtonToggle);
       fixture.detectChanges();
 
-      testComponent = fixture.debugElement.componentInstance;
-
       buttonToggleDebugElement = fixture.debugElement.query(By.directive(MatButtonToggle));
       buttonToggleNativeElement = buttonToggleDebugElement.nativeElement;
       buttonToggleLabelElement = fixture.debugElement.query(By.css('label')).nativeElement;

src/lib/checkbox/checkbox.spec.ts

@@ -748,7 +748,6 @@ describe('MatCheckbox', () => {
     let checkboxNativeElement: HTMLElement;
     let testComponent: CheckboxWithTabIndex;
     let inputElement: HTMLInputElement;
-    let labelElement: HTMLLabelElement;
 
     beforeEach(() => {
       fixture = TestBed.createComponent(CheckboxWithTabIndex);
@@ -758,7 +757,6 @@ describe('MatCheckbox', () => {
       checkboxDebugElement = fixture.debugElement.query(By.directive(MatCheckbox));
       checkboxNativeElement = checkboxDebugElement.nativeElement;
       inputElement = <HTMLInputElement>checkboxNativeElement.querySelector('input');
-      labelElement = <HTMLLabelElement>checkboxNativeElement.querySelector('label');
     });
 
     it('should preserve any given tabIndex', () => {
@@ -940,7 +938,6 @@ describe('MatCheckbox', () => {
 
   describe('without label', () => {
     let testComponent: CheckboxWithoutLabel;
-    let checkboxElement: HTMLElement;
     let checkboxInnerContainer: HTMLElement;
 
     beforeEach(() => {
@@ -949,7 +946,6 @@ describe('MatCheckbox', () => {
       const checkboxDebugEl = fixture.debugElement.query(By.directive(MatCheckbox));
 
       testComponent = fixture.componentInstance;
-      checkboxElement = checkboxDebugEl.nativeElement;
       checkboxInnerContainer = checkboxDebugEl
         .query(By.css('.mat-checkbox-inner-container')).nativeElement;
     });

src/lib/chips/chip-list.spec.ts

@@ -455,15 +455,13 @@ describe('MatChipList', () => {
   });
 
   describe('forms integration', () => {
-    let formField: HTMLElement;
     let nativeChips: HTMLElement[];
 
     describe('single selection', () => {
       beforeEach(() => {
         fixture = TestBed.createComponent(BasicChipList);
         fixture.detectChanges();
 
-        formField = fixture.debugElement.query(By.css('.mat-form-field')).nativeElement;
         nativeChips = fixture.debugElement.queryAll(By.css('mat-chip'))
           .map((chip) => chip.nativeElement);
         chips = fixture.componentInstance.chips;
@@ -627,7 +625,6 @@ describe('MatChipList', () => {
         fixture = TestBed.createComponent(MultiSelectionChipList);
         fixture.detectChanges();
 
-        formField = fixture.debugElement.query(By.css('.mat-form-field')).nativeElement;
         nativeChips = fixture.debugElement.queryAll(By.css('mat-chip'))
           .map((chip) => chip.nativeElement);
         chips = fixture.componentInstance.chips;
@@ -705,14 +702,12 @@ describe('MatChipList', () => {
   });
 
   describe('chip list with chip input', () => {
-    let formField: HTMLElement;
     let nativeChips: HTMLElement[];
 
     beforeEach(() => {
       fixture = TestBed.createComponent(InputChipList);
       fixture.detectChanges();
 
-      formField = fixture.debugElement.query(By.css('.mat-form-field')).nativeElement;
       nativeChips = fixture.debugElement.queryAll(By.css('mat-chip'))
         .map((chip) => chip.nativeElement);
     });

src/lib/chips/chip-list.ts

@@ -389,6 +389,11 @@ export class MatChipList extends _MatChipListMixinBase implements MatFormFieldCo
     if (this._changeSubscription) {
       this._changeSubscription.unsubscribe();
     }
+
+    if (this._chipRemoveSubscription) {
+      this._chipRemoveSubscription.unsubscribe();
+    }
+
     this._dropSubscriptions();
     this.stateChanges.complete();
   }

src/lib/chips/chip.spec.ts

@@ -4,13 +4,12 @@ import {createKeyboardEvent} from '@angular/cdk/testing';
 import {Component, DebugElement} from '@angular/core';
 import {async, ComponentFixture, TestBed} from '@angular/core/testing';
 import {By} from '@angular/platform-browser';
-import {MatChip, MatChipEvent, MatChipList, MatChipSelectionChange, MatChipsModule} from './index';
+import {MatChip, MatChipEvent, MatChipSelectionChange, MatChipsModule} from './index';
 
 
 describe('Chips', () => {
   let fixture: ComponentFixture<any>;
   let chipDebugElement: DebugElement;
-  let chipListNativeElement: HTMLElement;
   let chipNativeElement: HTMLElement;
   let chipInstance: MatChip;
 
@@ -59,7 +58,6 @@ describe('Chips', () => {
       fixture.detectChanges();
 
       chipDebugElement = fixture.debugElement.query(By.directive(MatChip));
-      chipListNativeElement = fixture.debugElement.query(By.directive(MatChipList)).nativeElement;
       chipNativeElement = chipDebugElement.nativeElement;
       chipInstance = chipDebugElement.injector.get(MatChip);
       testComponent = fixture.debugElement.componentInstance;

src/lib/core/ripple/ripple.spec.ts

@@ -543,14 +543,12 @@ describe('MatRipple', () => {
 
   describe('configuring behavior', () => {
     let controller: RippleContainerWithInputBindings;
-    let rippleComponent: MatRipple;
 
     beforeEach(() => {
       fixture = TestBed.createComponent(RippleContainerWithInputBindings);
       fixture.detectChanges();
 
       controller = fixture.debugElement.componentInstance;
-      rippleComponent = controller.ripple;
       rippleTarget = fixture.debugElement.nativeElement.querySelector('[mat-ripple]');
     });
 

src/lib/datepicker/month-view.spec.ts

@@ -262,7 +262,6 @@ describe('MatMonthView', () => {
 
   describe('month view with date filter', () => {
     let fixture: ComponentFixture<MonthViewWithDateFilter>;
-    let testComponent: MonthViewWithDateFilter;
     let monthViewNativeElement: Element;
 
     beforeEach(() => {
@@ -271,7 +270,6 @@ describe('MatMonthView', () => {
 
       let monthViewDebugElement = fixture.debugElement.query(By.directive(MatMonthView));
       monthViewNativeElement = monthViewDebugElement.nativeElement;
-      testComponent = fixture.componentInstance;
     });
 
     it('should disable filtered dates', () => {

src/lib/datepicker/multi-year-view.spec.ts

@@ -225,7 +225,6 @@ describe('MatMultiYearView', () => {
 
   describe('multi year view with date filter', () => {
     let fixture: ComponentFixture<MultiYearViewWithDateFilter>;
-    let testComponent: MultiYearViewWithDateFilter;
     let multiYearViewNativeElement: Element;
 
     beforeEach(() => {
@@ -234,7 +233,6 @@ describe('MatMultiYearView', () => {
 
       const multiYearViewDebugElement = fixture.debugElement.query(By.directive(MatMultiYearView));
       multiYearViewNativeElement = multiYearViewDebugElement.nativeElement;
-      testComponent = fixture.componentInstance;
     });
 
     it('should disablex years with no enabled days', () => {

src/lib/datepicker/year-view.spec.ts

@@ -293,7 +293,6 @@ describe('MatYearView', () => {
 
   describe('year view with date filter', () => {
     let fixture: ComponentFixture<YearViewWithDateFilter>;
-    let testComponent: YearViewWithDateFilter;
     let yearViewNativeElement: Element;
 
     beforeEach(() => {
@@ -302,7 +301,6 @@ describe('MatYearView', () => {
 
       const yearViewDebugElement = fixture.debugElement.query(By.directive(MatYearView));
       yearViewNativeElement = yearViewDebugElement.nativeElement;
-      testComponent = fixture.componentInstance;
     });
 
     it('should disable months with no enabled days', () => {

src/lib/list/list.ts

@@ -109,7 +109,6 @@ export class MatListSubheaderCssMatStyler {}
 })
 export class MatListItem extends _MatListItemMixinBase implements AfterContentInit,
     CanDisableRipple {
-  private _lineSetter: MatLineSetter;
   private _isNavList: boolean = false;
 
   @ContentChildren(MatLine) _lines: QueryList<MatLine>;
@@ -130,7 +129,9 @@ export class MatListItem extends _MatListItemMixinBase implements AfterContentIn
   }
 
   ngAfterContentInit() {
-    this._lineSetter = new MatLineSetter(this._lines, this._element);
+    // TODO: consider turning the setter into a function, it doesn't do anything as a class.
+    // tslint:disable-next-line:no-unused-expression
+    new MatLineSetter(this._lines, this._element);
   }
 
   /** Whether this list item should show a ripple effect when clicked. */