@ngdoc filter
@name limitTo
@kind function

@description
Creates a new array or string containing only a specified number of elements. The elements are
taken from either the beginning or the end of the source array, string or number, as specified by
the value and sign (positive or negative) of `limit`. Other array-like objects are also supported
(e.g. array subclasses, NodeLists, jqLite/jQuery collections etc). If a number is used as input,
it is converted to a string.

@param {Array|ArrayLike|string|number} input - Array/array-like, string or number to be limited.
@param {string|number} limit - The length of the returned array or string. If the `limit` number
is positive, `limit` number of items from the beginning of the source array/string are copied.
If the number is negative, `limit` number  of items from the end of the source array/string
are copied. The `limit` will be trimmed if it exceeds `array.length`. If `limit` is undefined,
the input will be returned unchanged.
@param {(string|number)=} begin - Index at which to begin limitation. As a negative index,
`begin` indicates an offset from the end of `input`. Defaults to `0`.
@returns {Array|string} A new sub-array or substring of length `limit` or less if the input had
less than `limit` elements.

@example
<example module="limitToExample" name="limit-to-filter">
<file name="index.html">
<script>
angular.module('limitToExample', [])
.controller('ExampleController', ['$scope', function($scope) {
$scope.numbers = [1,2,3,4,5,6,7,8,9];
$scope.letters = "abcdefghi";
$scope.longNumber = 2345432342;
$scope.numLimit = 3;
$scope.letterLimit = 3;
$scope.longNumberLimit = 3;
}]);
</script>
<div ng-controller="ExampleController">
<label>
Limit {{numbers}} to:
<input type="number" step="1" ng-model="numLimit">
</label>
<p>Output numbers: {{ numbers | limitTo:numLimit }}</p>
<label>
Limit {{letters}} to:
<input type="number" step="1" ng-model="letterLimit">
</label>
<p>Output letters: {{ letters | limitTo:letterLimit }}</p>
<label>
Limit {{longNumber}} to:
<input type="number" step="1" ng-model="longNumberLimit">
</label>
<p>Output long number: {{ longNumber | limitTo:longNumberLimit }}</p>
</div>
</file>
<file name="protractor.js" type="protractor">
var numLimitInput = element(by.model('numLimit'));
var letterLimitInput = element(by.model('letterLimit'));
var longNumberLimitInput = element(by.model('longNumberLimit'));
var limitedNumbers = element(by.binding('numbers | limitTo:numLimit'));
var limitedLetters = element(by.binding('letters | limitTo:letterLimit'));
var limitedLongNumber = element(by.binding('longNumber | limitTo:longNumberLimit'));

it('should limit the number array to first three items', function() {
expect(numLimitInput.getAttribute('value')).toBe('3');
expect(letterLimitInput.getAttribute('value')).toBe('3');
expect(longNumberLimitInput.getAttribute('value')).toBe('3');
expect(limitedNumbers.getText()).toEqual('Output numbers: [1,2,3]');
expect(limitedLetters.getText()).toEqual('Output letters: abc');
expect(limitedLongNumber.getText()).toEqual('Output long number: 234');
});

There is a bug in safari and protractor that doesn't like the minus key
it('should update the output when -3 is entered', function() {
numLimitInput.clear();
numLimitInput.sendKeys('-3');
letterLimitInput.clear();
letterLimitInput.sendKeys('-3');
longNumberLimitInput.clear();
longNumberLimitInput.sendKeys('-3');
expect(limitedNumbers.getText()).toEqual('Output numbers: [7,8,9]');
expect(limitedLetters.getText()).toEqual('Output letters: ghi');
expect(limitedLongNumber.getText()).toEqual('Output long number: 342');
});

it('should not exceed the maximum size of input array', function() {
numLimitInput.clear();
numLimitInput.sendKeys('100');
letterLimitInput.clear();
letterLimitInput.sendKeys('100');
longNumberLimitInput.clear();
longNumberLimitInput.sendKeys('100');
expect(limitedNumbers.getText()).toEqual('Output numbers: [1,2,3,4,5,6,7,8,9]');
expect(limitedLetters.getText()).toEqual('Output letters: abcdefghi');
expect(limitedLongNumber.getText()).toEqual('Output long number: 2345432342');
});
</file>
</example>
function limitToFilter() {
  return function(input, limit, begin) {
    if (Math.abs(Number(limit)) === Infinity) {
      limit = Number(limit);
    } else {
      limit = toInt(limit);
    }
    if (isNumberNaN(limit)) return input;

    if (isNumber(input)) input = input.toString();
    if (!isArrayLike(input)) return input;

    begin = (!begin || isNaN(begin)) ? 0 : toInt(begin);
    begin = (begin < 0) ? Math.max(0, input.length + begin) : begin;

    if (limit >= 0) {
      return sliceFn(input, begin, begin + limit);
    } else {
      if (begin === 0) {
        return sliceFn(input, limit, input.length);
      } else {
        return sliceFn(input, Math.max(0, begin + limit), begin);
      }
    }
  };
}