436 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			TypeScript
		
	
	
	
	
	
			
		
		
	
	
			436 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			TypeScript
		
	
	
	
	
	
/**
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 * @license
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 * Copyright Google Inc. All Rights Reserved.
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 *
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 * Use of this source code is governed by an MIT-style license that can be
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 * found in the LICENSE file at https://angular.io/license
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 */
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import {CommonModule} from '@angular/common';
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import {Component, ContentChild, TemplateRef} from '@angular/core';
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import {TestBed, async} from '@angular/core/testing';
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import {By} from '@angular/platform-browser/src/dom/debug/by';
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import {expect} from '@angular/platform-browser/testing/matchers';
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import {ListWrapper} from '../../src/facade/collection';
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let thisArg: any;
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export function main() {
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  describe('ngFor', () => {
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    const TEMPLATE =
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        '<div><copy-me template="ngFor let item of items">{{item.toString()}};</copy-me></div>';
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    beforeEach(() => {
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      TestBed.configureTestingModule(
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          {declarations: [TestComponent, ComponentUsingTestComponent], imports: [CommonModule]});
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    });
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    it('should reflect initial elements', async(() => {
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         TestBed.overrideComponent(TestComponent, {set: {template: TEMPLATE}});
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         let fixture = TestBed.createComponent(TestComponent);
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('1;2;');
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       }));
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    it('should reflect added elements', async(() => {
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         TestBed.overrideComponent(TestComponent, {set: {template: TEMPLATE}});
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         let fixture = TestBed.createComponent(TestComponent);
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         fixture.detectChanges();
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         (<number[]>fixture.debugElement.componentInstance.items).push(3);
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('1;2;3;');
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       }));
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    it('should reflect removed elements', async(() => {
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         TestBed.overrideComponent(TestComponent, {set: {template: TEMPLATE}});
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         let fixture = TestBed.createComponent(TestComponent);
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         fixture.detectChanges();
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         ListWrapper.removeAt(fixture.debugElement.componentInstance.items, 1);
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('1;');
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       }));
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    it('should reflect moved elements', async(() => {
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         TestBed.overrideComponent(TestComponent, {set: {template: TEMPLATE}});
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         let fixture = TestBed.createComponent(TestComponent);
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         fixture.detectChanges();
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         ListWrapper.removeAt(fixture.debugElement.componentInstance.items, 0);
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         (<number[]>fixture.debugElement.componentInstance.items).push(1);
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('2;1;');
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       }));
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    it('should reflect a mix of all changes (additions/removals/moves)', async(() => {
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         TestBed.overrideComponent(TestComponent, {set: {template: TEMPLATE}});
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         let fixture = TestBed.createComponent(TestComponent);
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         fixture.debugElement.componentInstance.items = [0, 1, 2, 3, 4, 5];
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         fixture.detectChanges();
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         fixture.debugElement.componentInstance.items = [6, 2, 7, 0, 4, 8];
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('6;2;7;0;4;8;');
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       }));
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    it('should iterate over an array of objects', async(() => {
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         const template = '<ul><li template="ngFor let item of items">{{item["name"]}};</li></ul>';
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         TestBed.overrideComponent(TestComponent, {set: {template: template}});
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         let fixture = TestBed.createComponent(TestComponent);
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         // INIT
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         fixture.debugElement.componentInstance.items = [{'name': 'misko'}, {'name': 'shyam'}];
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('misko;shyam;');
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         // GROW
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         (<any[]>fixture.debugElement.componentInstance.items).push({'name': 'adam'});
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('misko;shyam;adam;');
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         // SHRINK
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         ListWrapper.removeAt(fixture.debugElement.componentInstance.items, 2);
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         ListWrapper.removeAt(fixture.debugElement.componentInstance.items, 0);
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('shyam;');
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       }));
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    it('should gracefully handle nulls', async(() => {
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         const template = '<ul><li template="ngFor let item of null">{{item}};</li></ul>';
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         TestBed.overrideComponent(TestComponent, {set: {template: template}});
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         let fixture = TestBed.createComponent(TestComponent);
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('');
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       }));
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    it('should gracefully handle ref changing to null and back', async(() => {
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         TestBed.overrideComponent(TestComponent, {set: {template: TEMPLATE}});
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         let fixture = TestBed.createComponent(TestComponent);
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('1;2;');
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         fixture.debugElement.componentInstance.items = null;
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('');
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         fixture.debugElement.componentInstance.items = [1, 2, 3];
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('1;2;3;');
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       }));
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    it('should throw on non-iterable ref and suggest using an array', async(() => {
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         TestBed.overrideComponent(TestComponent, {set: {template: TEMPLATE}});
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         let fixture = TestBed.createComponent(TestComponent);
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         fixture.debugElement.componentInstance.items = 'whaaa';
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         expect(() => fixture.detectChanges())
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             .toThrowError(
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                 /Cannot find a differ supporting object 'whaaa' of type 'string'. NgFor only supports binding to Iterables such as Arrays/);
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       }));
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    it('should throw on ref changing to string', async(() => {
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         TestBed.overrideComponent(TestComponent, {set: {template: TEMPLATE}});
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         let fixture = TestBed.createComponent(TestComponent);
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('1;2;');
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         fixture.debugElement.componentInstance.items = 'whaaa';
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         expect(() => fixture.detectChanges()).toThrowError();
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       }));
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    it('should works with duplicates', async(() => {
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         TestBed.overrideComponent(TestComponent, {set: {template: TEMPLATE}});
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         let fixture = TestBed.createComponent(TestComponent);
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         var a = new Foo();
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         fixture.debugElement.componentInstance.items = [a, a];
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('foo;foo;');
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       }));
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    it('should repeat over nested arrays', async(() => {
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         const template = '<div>' +
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             '<div template="ngFor let item of items">' +
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             '<div template="ngFor let subitem of item">' +
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             '{{subitem}}-{{item.length}};' +
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             '</div>|' +
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             '</div>' +
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             '</div>';
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         TestBed.overrideComponent(TestComponent, {set: {template: template}});
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         let fixture = TestBed.createComponent(TestComponent);
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         fixture.debugElement.componentInstance.items = [['a', 'b'], ['c']];
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         fixture.detectChanges();
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         fixture.detectChanges();
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('a-2;b-2;|c-1;|');
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         fixture.debugElement.componentInstance.items = [['e'], ['f', 'g']];
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('e-1;|f-2;g-2;|');
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       }));
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    it('should repeat over nested arrays with no intermediate element', async(() => {
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         const template = '<div><template ngFor let-item [ngForOf]="items">' +
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             '<div template="ngFor let subitem of item">' +
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             '{{subitem}}-{{item.length}};' +
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             '</div></template></div>';
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         TestBed.overrideComponent(TestComponent, {set: {template: template}});
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         let fixture = TestBed.createComponent(TestComponent);
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         fixture.debugElement.componentInstance.items = [['a', 'b'], ['c']];
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('a-2;b-2;c-1;');
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         fixture.debugElement.componentInstance.items = [['e'], ['f', 'g']];
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('e-1;f-2;g-2;');
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       }));
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    it('should repeat over nested ngIf that are the last node in the ngFor temlate', async(() => {
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         const template =
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             `<div><template ngFor let-item [ngForOf]="items" let-i="index"><div>{{i}}|</div>` +
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             `<div *ngIf="i % 2 == 0">even|</div></template></div>`;
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         TestBed.overrideComponent(TestComponent, {set: {template: template}});
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         let fixture = TestBed.createComponent(TestComponent);
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         const el = fixture.debugElement.nativeElement;
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         const items = [1];
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         fixture.debugElement.componentInstance.items = items;
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         fixture.detectChanges();
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         expect(el).toHaveText('0|even|');
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         items.push(1);
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         fixture.detectChanges();
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         expect(el).toHaveText('0|even|1|');
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         items.push(1);
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         fixture.detectChanges();
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         expect(el).toHaveText('0|even|1|2|even|');
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       }));
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    it('should display indices correctly', async(() => {
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         const template =
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             '<div><copy-me template="ngFor: let item of items; let i=index">{{i.toString()}}</copy-me></div>';
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         TestBed.overrideComponent(TestComponent, {set: {template: template}});
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         let fixture = TestBed.createComponent(TestComponent);
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         fixture.debugElement.componentInstance.items = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('0123456789');
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         fixture.debugElement.componentInstance.items = [1, 2, 6, 7, 4, 3, 5, 8, 9, 0];
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('0123456789');
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       }));
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    it('should display first item correctly', async(() => {
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         const template =
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             '<div><copy-me template="ngFor: let item of items; let isFirst=first">{{isFirst.toString()}}</copy-me></div>';
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         TestBed.overrideComponent(TestComponent, {set: {template: template}});
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         let fixture = TestBed.createComponent(TestComponent);
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         fixture.debugElement.componentInstance.items = [0, 1, 2];
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('truefalsefalse');
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         fixture.debugElement.componentInstance.items = [2, 1];
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('truefalse');
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       }));
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    it('should display last item correctly', async(() => {
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         const template =
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             '<div><copy-me template="ngFor: let item of items; let isLast=last">{{isLast.toString()}}</copy-me></div>';
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         TestBed.overrideComponent(TestComponent, {set: {template: template}});
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         let fixture = TestBed.createComponent(TestComponent);
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         fixture.debugElement.componentInstance.items = [0, 1, 2];
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('falsefalsetrue');
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         fixture.debugElement.componentInstance.items = [2, 1];
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('falsetrue');
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       }));
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    it('should display even items correctly', async(() => {
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         const template =
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             '<div><copy-me template="ngFor: let item of items; let isEven=even">{{isEven.toString()}}</copy-me></div>';
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         TestBed.overrideComponent(TestComponent, {set: {template: template}});
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         let fixture = TestBed.createComponent(TestComponent);
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         fixture.debugElement.componentInstance.items = [0, 1, 2];
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('truefalsetrue');
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         fixture.debugElement.componentInstance.items = [2, 1];
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('truefalse');
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       }));
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    it('should display odd items correctly', async(() => {
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         const template =
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             '<div><copy-me template="ngFor: let item of items; let isOdd=odd">{{isOdd.toString()}}</copy-me></div>';
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         TestBed.overrideComponent(TestComponent, {set: {template: template}});
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         let fixture = TestBed.createComponent(TestComponent);
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         fixture.debugElement.componentInstance.items = [0, 1, 2, 3];
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('falsetruefalsetrue');
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         fixture.debugElement.componentInstance.items = [2, 1];
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         fixture.detectChanges();
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         expect(fixture.debugElement.nativeElement).toHaveText('falsetrue');
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       }));
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    it('should allow to use a custom template', async(() => {
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         const tcTemplate =
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             '<ul><template ngFor [ngForOf]="items" [ngForTemplate]="contentTpl"></template></ul>';
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         TestBed.overrideComponent(TestComponent, {set: {template: tcTemplate}});
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         const cutTemplate =
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             '<test-cmp><li template="let item; let i=index">{{i}}: {{item}};</li></test-cmp>';
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         TestBed.overrideComponent(ComponentUsingTestComponent, {set: {template: cutTemplate}});
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         let fixture = TestBed.createComponent(ComponentUsingTestComponent);
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         const testComponent = fixture.debugElement.children[0];
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         testComponent.componentInstance.items = ['a', 'b', 'c'];
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         fixture.detectChanges();
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         expect(testComponent.nativeElement).toHaveText('0: a;1: b;2: c;');
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       }));
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    it('should use a default template if a custom one is null', async(() => {
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         const testTemplate = `<ul><template ngFor let-item [ngForOf]="items" 
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            [ngForTemplate]="contentTpl" let-i="index">{{i}}: {{item}};</template></ul>`;
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         TestBed.overrideComponent(TestComponent, {set: {template: testTemplate}});
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         const cutTemplate =
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             '<test-cmp><li template="let item; let i=index">{{i}}: {{item}};</li></test-cmp>';
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         TestBed.overrideComponent(ComponentUsingTestComponent, {set: {template: cutTemplate}});
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         let fixture = TestBed.createComponent(ComponentUsingTestComponent);
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         const testComponent = fixture.debugElement.children[0];
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         testComponent.componentInstance.items = ['a', 'b', 'c'];
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         fixture.detectChanges();
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         expect(testComponent.nativeElement).toHaveText('0: a;1: b;2: c;');
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       }));
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    it('should use a custom template when both default and a custom one are present', async(() => {
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         const testTemplate = `<ul><template ngFor let-item [ngForOf]="items"
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         [ngForTemplate]="contentTpl" let-i="index">{{i}}=> {{item}};</template></ul>`;
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         TestBed.overrideComponent(TestComponent, {set: {template: testTemplate}});
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         const cutTemplate =
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             '<test-cmp><li template="let item; let i=index">{{i}}: {{item}};</li></test-cmp>';
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         TestBed.overrideComponent(ComponentUsingTestComponent, {set: {template: cutTemplate}});
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         let fixture = TestBed.createComponent(ComponentUsingTestComponent);
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         const testComponent = fixture.debugElement.children[0];
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         testComponent.componentInstance.items = ['a', 'b', 'c'];
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         fixture.detectChanges();
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         expect(testComponent.nativeElement).toHaveText('0: a;1: b;2: c;');
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       }));
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    describe('track by', () => {
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      it('should set the context to the component instance', async(() => {
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           const template =
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               `<template ngFor let-item [ngForOf]="items" [ngForTrackBy]="trackByContext.bind(this)"></template>`;
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           TestBed.overrideComponent(TestComponent, {set: {template: template}});
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           let fixture = TestBed.createComponent(TestComponent);
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           thisArg = null;
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           fixture.detectChanges();
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           expect(thisArg).toBe(fixture.debugElement.componentInstance);
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         }));
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      it('should not replace tracked items', async(() => {
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           const template =
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               `<template ngFor let-item [ngForOf]="items" [ngForTrackBy]="trackById" let-i="index">
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               <p>{{items[i]}}</p>
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              </template>`;
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           TestBed.overrideComponent(TestComponent, {set: {template: template}});
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           let fixture = TestBed.createComponent(TestComponent);
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           var buildItemList = () => {
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             fixture.debugElement.componentInstance.items = [{'id': 'a'}];
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             fixture.detectChanges();
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             return fixture.debugElement.queryAll(By.css('p'))[0];
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           };
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           var firstP = buildItemList();
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           var finalP = buildItemList();
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           expect(finalP.nativeElement).toBe(firstP.nativeElement);
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         }));
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      it('should update implicit local variable on view', async(() => {
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           const template =
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               `<div><template ngFor let-item [ngForOf]="items" [ngForTrackBy]="trackById">{{item['color']}}</template></div>`;
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           TestBed.overrideComponent(TestComponent, {set: {template: template}});
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           let fixture = TestBed.createComponent(TestComponent);
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           fixture.debugElement.componentInstance.items = [{'id': 'a', 'color': 'blue'}];
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           fixture.detectChanges();
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           expect(fixture.debugElement.nativeElement).toHaveText('blue');
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           fixture.debugElement.componentInstance.items = [{'id': 'a', 'color': 'red'}];
 | 
						|
           fixture.detectChanges();
 | 
						|
           expect(fixture.debugElement.nativeElement).toHaveText('red');
 | 
						|
         }));
 | 
						|
      it('should move items around and keep them updated ', async(() => {
 | 
						|
           const template =
 | 
						|
               `<div><template ngFor let-item [ngForOf]="items" [ngForTrackBy]="trackById">{{item['color']}}</template></div>`;
 | 
						|
           TestBed.overrideComponent(TestComponent, {set: {template: template}});
 | 
						|
           let fixture = TestBed.createComponent(TestComponent);
 | 
						|
 | 
						|
           fixture.debugElement.componentInstance.items =
 | 
						|
               [{'id': 'a', 'color': 'blue'}, {'id': 'b', 'color': 'yellow'}];
 | 
						|
           fixture.detectChanges();
 | 
						|
           expect(fixture.debugElement.nativeElement).toHaveText('blueyellow');
 | 
						|
           fixture.debugElement.componentInstance.items =
 | 
						|
               [{'id': 'b', 'color': 'orange'}, {'id': 'a', 'color': 'red'}];
 | 
						|
           fixture.detectChanges();
 | 
						|
           expect(fixture.debugElement.nativeElement).toHaveText('orangered');
 | 
						|
         }));
 | 
						|
 | 
						|
      it('should handle added and removed items properly when tracking by index', async(() => {
 | 
						|
           const template =
 | 
						|
               `<div><template ngFor let-item [ngForOf]="items" [ngForTrackBy]="trackByIndex">{{item}}</template></div>`;
 | 
						|
           TestBed.overrideComponent(TestComponent, {set: {template: template}});
 | 
						|
           let fixture = TestBed.createComponent(TestComponent);
 | 
						|
 | 
						|
           fixture.debugElement.componentInstance.items = ['a', 'b', 'c', 'd'];
 | 
						|
           fixture.detectChanges();
 | 
						|
           fixture.debugElement.componentInstance.items = ['e', 'f', 'g', 'h'];
 | 
						|
           fixture.detectChanges();
 | 
						|
           fixture.debugElement.componentInstance.items = ['e', 'f', 'h'];
 | 
						|
           fixture.detectChanges();
 | 
						|
           expect(fixture.debugElement.nativeElement).toHaveText('efh');
 | 
						|
         }));
 | 
						|
    });
 | 
						|
  });
 | 
						|
}
 | 
						|
 | 
						|
class Foo {
 | 
						|
  toString() { return 'foo'; }
 | 
						|
}
 | 
						|
 | 
						|
@Component({selector: 'test-cmp', template: ''})
 | 
						|
class TestComponent {
 | 
						|
  @ContentChild(TemplateRef) contentTpl: TemplateRef<Object>;
 | 
						|
  items: any;
 | 
						|
  constructor() { this.items = [1, 2]; }
 | 
						|
  trackById(index: number, item: any): string { return item['id']; }
 | 
						|
  trackByIndex(index: number, item: any): number { return index; }
 | 
						|
  trackByContext(): void { thisArg = this; }
 | 
						|
}
 | 
						|
 | 
						|
@Component({selector: 'outer-cmp', template: ''})
 | 
						|
class ComponentUsingTestComponent {
 | 
						|
  items: any;
 | 
						|
  constructor() { this.items = [1, 2]; }
 | 
						|
}
 |