objectSpread not working with boolean arguments

[MengMengYan]

Hi,
We have a scenario where objectSpread throws an exception when the arguments list contains a boolean.

This particular piece of code

function _objectSpread(target) {
  for (var i = 1; i < arguments.length; i++) {
    var source = arguments[i] != null  ? arguments[i] : {};
    var ownKeys = Object.keys(source);

    if (typeof Object.getOwnPropertySymbols === 'function') {
      ownKeys = ownKeys.concat(Object.getOwnPropertySymbols(source).filter(function (sym) {
        return Object.getOwnPropertyDescriptor(source, sym).enumerable;
      }));
    }

    ownKeys.forEach(function (key) {
      defineProperty(target, key, source[key]);
    });
  }

  return target;
}

gives an exception : Object.keys argument is not an object.

Shouldn't the check be like:
var source = arguments[i] != null && typeof arguments[i] === 'object' ? arguments[i] : {};

[babel-bot]

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[nicolo-ribaudo]

Object.keys should support boolean arguments. You might need to load a polyfill.

[chrishinrichs]

@nicolo-ribaudo this fails in IE11, which has Object.keys natively - seems like this should be fixed as we're using a babel-preset-env setting that should include IE11 and this issue did not occur with babel@6

[peey]

@chrishinrichs the spec for Object.keys dictates that it should work for booleans. IE11 might be deviating from the spec.

Can you check if Object.keys(new Object(boolean)) works? Your browser's supposed to be doing something similar internally.

[chrishinrichs]

@peey from what I can gather, IE11 implements the ES5 version of Object.keys which specified that the argument had to be an Object (http://ecma-international.org/ecma-262/5.1/#sec-15.2.3.14). The ES6 spec changed to indicate it should be coerced to an object, which is what modern browsers do (http://ecma-international.org/ecma-262/6.0/index.html#sec-object.keys).

I confirmed that Object.keys(Object(boolean)) works in IE11 and have updated my PR accordingly.