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var R = require('../source');var eq = require('./shared/eq');
describe('transduce', function() {  var add = R.add;  var mult = function(a, b) {return a * b;};  var isOdd = function(b) {return b % 2 === 1;};  var square = function(a) {return a * a;};  var addxf = {    '@@transducer/step': function(acc, x) { return acc + x; },    '@@transducer/init': function() { return 0; },    '@@transducer/result': function(x) { return x; }  };
  var listxf = {    '@@transducer/step': function(acc, x) { return acc.concat([x]); },    '@@transducer/init': function() { return []; },    '@@transducer/result': function(x) { return x; }  };
  var multxf = {    '@@transducer/step': function(acc, x) { return acc * x; },    '@@transducer/init': function() { return 1; },    '@@transducer/result': function(x) { return x; }  };
  var toxf = function(fn) {    return function(xf) {      return {        f: fn,        '@@transducer/step': xf['@@transducer/step'],        '@@transducer/result': xf['@@transducer/result'],        xf: xf      };    };  };
  it('transduces into arrays', function() {    eq(R.transduce(R.map(add(1)), R.flip(R.append), [], [1, 2, 3, 4]), [2, 3, 4, 5]);    eq(R.transduce(R.filter(isOdd), R.flip(R.append), [],  [1, 2, 3, 4]), [1, 3]);    eq(R.transduce(R.compose(R.map(add(1)), R.take(2)), R.flip(R.append), [],  [1, 2, 3, 4]), [2, 3]);    eq(R.transduce(R.compose(R.filter(isOdd), R.take(1)), R.flip(R.append), [],  [1, 2, 3, 4]), [1]);  });
  it('transduces into strings', function() {    var _add = function(x, y) { return x + y; };    eq(R.transduce(R.map(R.inc), _add, '', [1, 2, 3, 4]), '2345');    eq(R.transduce(R.filter(isOdd), _add, '', [1, 2, 3, 4]), '13');    eq(R.transduce(R.compose(R.map(add(1)), R.take(2)), _add, '', [1, 2, 3, 4]), '23');  });
  it('transduces into objects', function() {    eq(R.transduce(R.map(R.identity), R.mergeRight, {}, [{a: 1}, {b: 2, c: 3}]), {a: 1, b: 2, c: 3});  });
  it('folds transformer objects over a collection with the supplied accumulator', function() {    eq(R.transduce(toxf(add), addxf, 0, [1, 2, 3, 4]), 10);    eq(R.transduce(toxf(mult), multxf, 1, [1, 2, 3, 4]), 24);    eq(R.transduce(toxf(R.concat), listxf, [0], [1, 2, 3, 4]), [0, 1, 2, 3, 4]);    eq(R.transduce(toxf(add), add, 0, [1, 2, 3, 4]), 10);    eq(R.transduce(toxf(mult), mult, 1, [1, 2, 3, 4]), 24);  });
  it('dispatches to objects that implement `reduce`', function() {    var obj = {x: [1, 2, 3], reduce: function() { return 'override'; }};    eq(R.transduce(R.map(add(1)), add, 0, obj), 'override');    eq(R.transduce(R.map(add(1)), add, 10, obj), 'override');  });
  it('returns the accumulator for an empty collection', function() {    eq(R.transduce(toxf(add), addxf, 0, []), 0);    eq(R.transduce(toxf(mult), multxf, 1, []), 1);    eq(R.transduce(toxf(R.concat), listxf, [], []), []);  });
  it('short circuits with reduced', function() {    var transducer = R.compose(R.map(square), R.filter(isOdd));    var iterator = function(acc, val) {return val > 10 ? R.reduced(acc) : R.append(val, acc);};    var getOddSquaresWhileLessThan10 = R.transduce(transducer, iterator, []);    eq(getOddSquaresWhileLessThan10([1, 2, 3, 4]), [1, 9]);  });});