Exported bindings are unexpectedly renamed. #267

Related #11, where you wrote:

I've changed some of the rewriting behaviour so that exported vars (or lets) are always rewritten as export.foo = .... Involves a little bit of dancing around, but I think it's the best solution. Hopefully I didn't introduce any bugs in the process.

Here’s my entry file I’m trying to rollup:

export {
  event,
  select,
  selectAll
} from "d3-selection";

The resulting code looks like this:

// initialization of event is incorrectly renamed “event$1”
exports.event$1 = null;

// likewise with assignment
function example(foo) {
  exports.event$1 = foo;
}

// then the initial value is copied into the exports object under the correct name
exports.event = exports.event$1;

So, two problems:

• There’s an undesired export “event$1” which has the correct value.
• The desired export “event” is always null.