Skip to main content
Module

x/ramda/test/pipeWith.js

:ram: Practical functional Javascript
Latest
File
var R = require('../source');var eq = require('./shared/eq');

describe('pipeWith', function() {
it('performs left-to-right function composition with function applying', function() { // f :: (String, Number?) -> ([Number] -> [Number]) var f = R.pipeWith(function(f, res) { return f(res); })([parseInt, R.multiply, R.map]);
eq(f.length, 2); eq(f('10')([1, 2, 3]), [10, 20, 30]); eq(f('10', 2)([1, 2, 3]), [2, 4, 6]); });
it('performs left-to-right function while not nil result', function() { var isOdd = R.flip(R.modulo)(2); var pipeWhenNotNil = R.pipeWith(function(f, res) { return R.isNil(res) ? null : f(res); });
var f = pipeWhenNotNil([parseInt, R.ifElse(isOdd, R.identity, R.always(null)), R.inc]);
eq(f.length, 2); eq(f('1'), 2); eq(f('2'), null); });
it('performs left-to-right function using promise chaining', function() { var then = function(f, p) { return p.then(f); }; var pipeP = R.pipeWith(then); var toListPromise = function(a) { return new Promise(function(res) { res([a]); }); }; var doubleListPromise = function(a) { return new Promise(function(res) { res(R.concat(a, a)); }); }; var f = pipeP([ toListPromise, doubleListPromise ]);
return f(1) .then(function(res) { eq(res, [1, 1]); }); });
});