/* object-assign © Sindre Sorhus @license MIT */

'use strict'; /* eslint-disable no-unused-vars */ var getOwnPropertySymbols = Object.getOwnPropertySymbols; var hasOwnProperty = Object.prototype.hasOwnProperty; var propIsEnumerable = Object.prototype.propertyIsEnumerable;

function toObject(val) {

if (val === null || val === undefined) {
        throw new TypeError('Object.assign cannot be called with null or undefined');
}

return Object(val);

}

function shouldUseNative() {

try {
        if (!Object.assign) {
                return false;
        }

        // Detect buggy property enumeration order in older V8 versions.

        // https://bugs.chromium.org/p/v8/issues/detail?id=4118
        var test1 = new String('abc');  // eslint-disable-line no-new-wrappers
        test1[5] = 'de';
        if (Object.getOwnPropertyNames(test1)[0] === '5') {
                return false;
        }

        // https://bugs.chromium.org/p/v8/issues/detail?id=3056
        var test2 = {};
        for (var i = 0; i < 10; i++) {
                test2['_' + String.fromCharCode(i)] = i;
        }
        var order2 = Object.getOwnPropertyNames(test2).map(function (n) {
                return test2[n];
        });
        if (order2.join('') !== '0123456789') {
                return false;
        }

        // https://bugs.chromium.org/p/v8/issues/detail?id=3056
        var test3 = {};
        'abcdefghijklmnopqrst'.split('').forEach(function (letter) {
                test3[letter] = letter;
        });
        if (Object.keys(Object.assign({}, test3)).join('') !==
                        'abcdefghijklmnopqrst') {
                return false;
        }

        return true;
} catch (err) {
        // We don't expect any of the above to throw, but better to be safe.
        return false;
}

}

module.exports = shouldUseNative() ? Object.assign : function (target, source) {

var from;
var to = toObject(target);
var symbols;

for (var s = 1; s < arguments.length; s++) {
        from = Object(arguments[s]);

        for (var key in from) {
                if (hasOwnProperty.call(from, key)) {
                        to[key] = from[key];
                }
        }

        if (getOwnPropertySymbols) {
                symbols = getOwnPropertySymbols(from);
                for (var i = 0; i < symbols.length; i++) {
                        if (propIsEnumerable.call(from, symbols[i])) {
                                to[symbols[i]] = from[symbols[i]];
                        }
                }
        }
}

return to;

};