109 lines
		
	
	
		
			3.6 KiB
		
	
	
	
		
			TypeScript
		
	
	
	
	
	
			
		
		
	
	
			109 lines
		
	
	
		
			3.6 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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| 
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| import {CommonModule, SlicePipe} from '@angular/common';
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| import {Component} from '@angular/core';
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| import {TestBed, async} from '@angular/core/testing';
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| import {expect} from '@angular/platform-browser/testing/src/matchers';
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| 
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| {
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|   describe('SlicePipe', () => {
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|     let list: number[];
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|     let str: string;
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|     let pipe: SlicePipe;
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| 
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|     beforeEach(() => {
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|       list = [1, 2, 3, 4, 5];
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|       str = 'tuvwxyz';
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|       pipe = new SlicePipe();
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|     });
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| 
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|     describe('supports', () => {
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|       it('should support strings', () => { expect(() => pipe.transform(str, 0)).not.toThrow(); });
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|       it('should support lists', () => { expect(() => pipe.transform(list, 0)).not.toThrow(); });
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| 
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|       it('should not support other objects',
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|          () => { expect(() => pipe.transform({}, 0)).toThrow(); });
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|     });
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| 
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|     describe('transform', () => {
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| 
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|       it('should return null if the value is null',
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|          () => { expect(pipe.transform(null, 1)).toBe(null); });
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| 
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|       it('should return all items after START index when START is positive and END is omitted',
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|          () => {
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|            expect(pipe.transform(list, 3)).toEqual([4, 5]);
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|            expect(pipe.transform(str, 3)).toEqual('wxyz');
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|          });
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| 
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|       it('should return last START items when START is negative and END is omitted', () => {
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|         expect(pipe.transform(list, -3)).toEqual([3, 4, 5]);
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|         expect(pipe.transform(str, -3)).toEqual('xyz');
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|       });
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| 
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|       it('should return all items between START and END index when START and END are positive',
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|          () => {
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|            expect(pipe.transform(list, 1, 3)).toEqual([2, 3]);
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|            expect(pipe.transform(str, 1, 3)).toEqual('uv');
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|          });
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| 
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|       it('should return all items between START and END from the end when START and END are negative',
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|          () => {
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|            expect(pipe.transform(list, -4, -2)).toEqual([2, 3]);
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|            expect(pipe.transform(str, -4, -2)).toEqual('wx');
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|          });
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| 
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|       it('should return an empty value if START is greater than END', () => {
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|         expect(pipe.transform(list, 4, 2)).toEqual([]);
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|         expect(pipe.transform(str, 4, 2)).toEqual('');
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|       });
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| 
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|       it('should return an empty value if START greater than input length', () => {
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|         expect(pipe.transform(list, 99)).toEqual([]);
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|         expect(pipe.transform(str, 99)).toEqual('');
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|       });
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| 
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|       it('should return entire input if START is negative and greater than input length', () => {
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|         expect(pipe.transform(list, -99)).toEqual([1, 2, 3, 4, 5]);
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|         expect(pipe.transform(str, -99)).toEqual('tuvwxyz');
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|       });
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| 
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|       it('should not modify the input list', () => {
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|         expect(pipe.transform(list, 2)).toEqual([3, 4, 5]);
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|         expect(list).toEqual([1, 2, 3, 4, 5]);
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|       });
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| 
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|     });
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| 
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|     describe('integration', () => {
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| 
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|       @Component({selector: 'test-comp', template: '{{(data | slice:1).join(",") }}'})
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|       class TestComp {
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|         data: any;
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|       }
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| 
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|       beforeEach(() => {
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|         TestBed.configureTestingModule({declarations: [TestComp], imports: [CommonModule]});
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|       });
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| 
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|       it('should work with mutable arrays', async(() => {
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|            const fixture = TestBed.createComponent(TestComp);
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|            const mutable: number[] = [1, 2];
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|            fixture.componentInstance.data = mutable;
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|            fixture.detectChanges();
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|            expect(fixture.nativeElement).toHaveText('2');
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| 
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|            mutable.push(3);
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|            fixture.detectChanges();
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|            expect(fixture.nativeElement).toHaveText('2,3');
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|          }));
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|     });
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|   });
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| }
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