import { ANNOTATIONS } from '@angular/core/src/util/decorators';
import { createPipe } from './pipe.factory';

describe('pipeFactory', () => {

    describe('createPipe', () => {
        const testArgs = [1, 2, 3];

        function reverseArgs(...args) {
            return args.reverse();
        }

        it('creates a new Pipe with the given function', () => {
            const Pipe = createPipe(reverseArgs);
            const pipe = new Pipe();

            expect(pipe.transform(testArgs)).toEqual(reverseArgs(testArgs));
        });

        it('uses the function name as pipe name by default', () => {
            const Pipe = createPipe(reverseArgs);

            expect(Pipe[ANNOTATIONS][0].name).toEqual('reverseArgs');
        });

        it('uses the optional second parameter as pipe name if given', () => {
            const Pipe = createPipe(reverseArgs, 'reverse');

            expect(Pipe[ANNOTATIONS][0].name).toEqual('reverse');
        });
    });
});