Issue with re-assigning exported local variable after declaration.

[rwjblue]

Input:

var foo = function() { }

if (false) {
  foo = function () { };  
}

export {
 foo 
}

Output:

define(['exports'], function (exports) {

  'use strict';

  var foo = function() { }

  if (false) {
    exports.foo = foo = function () { };  
  }

});

---

This causes some issues in Ember, and we have locked Esperanto down to 0.6.17 temporarily (in emberjs/ember.js#10751).

[Rich-Harris]

Ah, yep, I think I see the problem. Thinking out loud: it's trying to avoid doing more exports.foo = ... than is necessary - this line is being run, because isTopLevelNode is true but shouldn't be. The problematic line is here - it's determining whether it's a top level node by seeing if it's in the top level scope, which obviously isn't the case since it's in a block. Should be an easy fix - thanks for raising it

[eventualbuddha]

I believe the expected output should include two exports.foo assignments, one inside the if, the other outside it.

[rwjblue]

@eventualbuddha - OK, I definitely defer that to y'all. My main issue is that there is no export.foo in the current output (because it is inside the if). I'll just remove the expected output....

[Rich-Harris]

Have opened #131, which fixes this but changes the approach slightly. Previously, esperanto would keep track of any assignments to exported bindings, so that it didn't need the final exports.foo = foo. A simpler approach in my view is to always have exports.foo = foo at the end, and not bother with changing the foo = ... into exports.foo = foo = ... inside the if block.

The one exception to this is when foo is assigned to inside a function body, since that could happen late. So for example this becomes this.

Does that sound right to everyone?

[Rich-Harris]

Released in 0.6.23