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'use strict';
var $ = require('../internals/export');
var uncurryThis = require('../internals/function-uncurry-this');
var requireObjectCoercible = require('../internals/require-object-coercible');
var toIntegerOrInfinity = require('../internals/to-integer-or-infinity');
var toString = require('../internals/to-string');
var stringSlice = uncurryThis(''.slice);
var max = Math.max;
var min = Math.min;
// eslint-disable-next-line unicorn/prefer-string-slice, es-x/no-string-prototype-substr -- required for testing
var FORCED = !''.substr || 'ab'.substr(-1) !== 'b';
// `String.prototype.substr` method
// https://tc39.es/ecma262/#sec-string.prototype.substr
$({ target: 'String', proto: true, forced: FORCED }, {
substr: function substr(start, length) {
var that = toString(requireObjectCoercible(this));
var size = that.length;
var intStart = toIntegerOrInfinity(start);
var intLength, intEnd;
if (intStart === Infinity) intStart = 0;
if (intStart < 0) intStart = max(size + intStart, 0);
intLength = length === undefined ? size : toIntegerOrInfinity(length);
if (intLength <= 0 || intLength === Infinity) return '';
intEnd = min(intStart + intLength, size);
return intStart >= intEnd ? '' : stringSlice(that, intStart, intEnd);
}
});