text: var assert = require('assert');
  
  var R = require('../source');
  var eq = require('./shared/eq');
  
  
  describe('mergeDeepWithKey', function() {
    function last(k, x, y) { return y; }
  
    it('takes two objects, recursively merges their own properties and returns a new object', function() {
      var a = { w: 1, x: 2, y: { z: 3 }};
      var b = { a: 4, b: 5, c: { d: 6 }};
      eq(R.mergeDeepWithKey(last, a, b), { w: 1, x: 2, y: { z: 3 }, a: 4, b: 5, c: { d: 6 }});
    });
  
    it('applies the provided function to the key, the value from the first object' +
      ' and the value from the second object to determine the value for keys that' +
      ' exist in both objects', function() {
      var a = { a: { b: 'B1', c: 'C' }, y: 'Y' };
      var b = { a: { b: 'B2', d: 'D' }, z: 'Z' };
      var c = R.mergeDeepWithKey(function(k, a, b) { return k + a + b; }, a, b);
      eq(c, { a: { b: 'bB1B2', c: 'C', d: 'D' }, y: 'Y', z: 'Z' });
    });
  
    it('is not destructive', function() {
      var a = { w: 1, x: { y: 2 }};
      var res = R.mergeDeepWithKey(last, a, { x: { y: 3 }});
      assert.notStrictEqual(a, res);
      assert.notStrictEqual(a.x, res.x);
      eq(res, { w: 1, x: { y: 3 }});
    });
  
    it('reports only own properties', function() {
      var a = { w: 1, x: { y: 2 }};
      function Cla() {}
      Cla.prototype.y = 5;
      eq(R.mergeDeepWithKey(last, { x: new Cla() }, a), { w: 1, x: { y: 2 }});
      eq(R.mergeDeepWithKey(last, a, { x: new Cla() }), { w: 1, x: { y: 2 }});
    });
  
  });
  