Support for react-native

[alex-mcleod]

Setting the DEV var causes release builds to fail on react native. I discovered this while using the react-intl library, which has a dependency on this library. So, I've removed usage of DEV to make this library compatible with react-native.

[zertosh]

The main point of this lib is to cache the value of process.env.NODE_ENV. See https://github.com/zertosh/invariant#node. Is the problem with the name __DEV__? How can I repro?

[ms88privat]

I want to start using this package with react-native too. I did not test it in production mode yet. But I know, that React-Native has a global __DEV__ variable by default and no process.env.NODE_EN I think.

[zertosh]

The react-native package already has an invariant haste module. Isn't it reachable from user code?

[alex-mcleod]

@zertosh it is the naming of the __DEV__ variable which is causing the issue, so perhaps the best solution in retrospect would be to just change the name of that variable to __DEVELOPMENT__. React native does have it's own invariant module, however this version of invariant is a dependency for the react-intl package which I wished to use with react-native.

[zertosh]

How about this then?

var NODE_ENV = process.env.NODE_ENV;

var invariant = function(condition, format, a, b, c, d, e, f) {
  if (NODE_ENV !== 'production') {
    if (format === undefined) {
      throw new Error('invariant requires an error message argument');
    }
  }

If that works, then please squash the commits and don't include a version bump.

[alex-mcleod]

That works. Have updated and squashed the commits.

[zertosh]

thanks! published as invariant@2.2.1