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var R = require('../source');var eq = require('./shared/eq');

var testList = [{a: 1}, {b: 2}, {c: 3}];
describe('lensIndex', function() {  describe('view', function() {    it('focuses list element at the specified index', function() {      eq(R.view(R.lensIndex(0), testList), {a: 1});    });    it('returns undefined if the specified index does not exist', function() {      eq(R.view(R.lensIndex(10), testList), undefined);    });  });  describe('set', function() {    it('sets the list value at the specified index', function() {      eq(R.set(R.lensIndex(0), 0, testList), [0, {b: 2}, {c: 3}]);    });  });  describe('over', function() {    it('applies function to the value at the specified list index', function() {      eq(R.over(R.lensIndex(2), R.keys, testList), [{a: 1}, {b: 2}, ['c']]);    });  });  describe('composability', function() {    it('can be composed', function() {      var nestedList = [0, [10, 11, 12], 1, 2];      var composedLens = R.compose(R.lensIndex(1), R.lensIndex(0));
      eq(R.view(composedLens, nestedList), 10);    });  });  describe('well behaved lens', function() {    it('set s (get s) === s', function() {      eq(R.set(R.lensIndex(0), R.view(R.lensIndex(0), testList), testList), testList);    });    it('get (set s v) === v', function() {      eq(R.view(R.lensIndex(0), R.set(R.lensIndex(0), 0, testList)), 0);    });    it('get (set(set s v1) v2) === v2', function() {      eq(        R.view(R.lensIndex(0), R.set(R.lensIndex(0), 11, R.set(R.lensIndex(0), 10, testList))),        11      );    });  });});