Error when using browserify moduleSystem about gulp-angular-templatecache

[miickel]

You shouldn't need to include the 2nd parameter (it holds data for the template, and is optional), I'm pretty sure something else made map-stream throw the TypeError.

Can you provide a minimal example, so we can reproduce the error?

[pselden]

Yes. Trying to narrow it down now -- it is something else that is included in my Gulpfile that is causing this issue. When I stripped it down to just the templates task it worked fine.

[pselden]

Yes -- it's something in https://github.com/thlorenz/es6ify that its causing it -- should have noticed from the stacktrace. Closing this issue and investigating further.

[pselden]

So... it looks like traceur, which is used by es6ify. Sets up a polyfill for Object.assign:

  function assign(target) {
    for (var i = 1; i < arguments.length; i++) {
      var source = arguments[i];
      var props = keys(source);
      var p,
          length = props.length;
      for (p = 0; p < length; p++) {
        var name = props[p];
        if (isPrivateName(name))
          continue;
        target[name] = source[name];
      }
    }
    return target;
  }

However, gulp-header relies on object-assign, which does something like this:

module.exports = Object.assign || function (target, source) {
   // implementation
}

When es6ify is required first, it creates the polyfill on Object.assign, which is returned by this function. The polyfill is incompatible with this version because it does not accept undefined as a parameter.

gulp-header recently switched to object-assign instead of lodash.assign for the extend functionality.

Note: passing in an empty data argument does fix the issue because it is able to assign {} instead of undefined.

[miickel]

Good catch! I think the cleanest solution here would be if you submitted a PR/issue to es6ify to suggest changing their polyfill into something that works more like the native Object.assign.

Gulp-header is a well-adopted plugin, so breaking it would affect a lot of build pipelines, which should motivate es6ify to make it compatible.