Is there a way to keep top-level import names constant in the output? #176
Description
We are looking with @trueadm into using Rollup for React.
My bundle (with a bunch of external dependencies) currently looks like this:
'use strict';
var require$$0 = require('react/lib/React');
var require$$0$1 = require('fbjs/lib/invariant');
var require$$2 = require('fbjs/lib/warning');
var require$$0$2 = require('fbjs/lib/ExecutionEnvironment');
var emptyFunction = require('fbjs/lib/emptyFunction');
var EventListener = require('fbjs/lib/EventListener');
var getUnboundedScrollPosition = require('fbjs/lib/getUnboundedScrollPosition');
var containsNode = require('fbjs/lib/containsNode');
var focusNode = require('fbjs/lib/focusNode');
var emptyObject = require('fbjs/lib/emptyObject');
var invariant$1 = require$$0$1;
// ...Notice how some top-level imports have nice names (e.g. EventListener) while others were renamed in place (e.g. require$$2). I noticed that renaming only seems to happen if there's a variable down below that “steals” the nice name:
'use strict';
var require$$0 = require('React');
// ...
var React = require$$0;Would it be possible to make sure that it’s always the other way around: the top-level imports keep their names, and any further references to them are renamed?
This is important for us because our internal require() transform mandates that the variable name matches the import name. So it always has to be var x = require('x'). In this example, the desired output would be:
'use strict';
var React = require('react/lib/React');
var invariant = require('fbjs/lib/invariant');
var warning = require('fbjs/lib/warning');
var ExecutionEnvironment = require('fbjs/lib/ExecutionEnvironment');
var emptyFunction = require('fbjs/lib/emptyFunction');
var EventListener = require('fbjs/lib/EventListener');
var getUnboundedScrollPosition = require('fbjs/lib/getUnboundedScrollPosition');
var containsNode = require('fbjs/lib/containsNode');
var focusNode = require('fbjs/lib/focusNode');
var emptyObject = require('fbjs/lib/emptyObject');
// ...
var require$$0 = React;
// etcThanks for consideration!
If you want to give this a try, you can run:
git clone https://github.com/trueadm/react.git
cd react
git checkout rollup
npm i
node scripts/rollup/build.js
and explore build/rollup/ReactDOM-core.js.