Non-static assignments to require are broken

[devongovett]

🐛 bug report

This code:

let x = require('./other');
x['fo' + 'o'] = 4;
output = require('./other').foo;

produces this:

(function () {
  // ASSET: src/other.js
  var $9bb2a74c22793326fe949cf11616aca2$exports = {};
  var $9bb2a74c22793326fe949cf11616aca2$export$foo = 2;
  $9bb2a74c22793326fe949cf11616aca2$exports.foo = $9bb2a74c22793326fe949cf11616aca2$export$foo;
  $9bb2a74c22793326fe949cf11616aca2$exports['fo' + 'o'] = 4;
  output = $9bb2a74c22793326fe949cf11616aca2$export$foo;
})();

The expected result is 4, but this will result in 2.

Fixing this will require tracking non-static assignments and bailing on resolving directly to variables instead of member expressions. The linker could replace static variable accesses with member expressions again if there is metadata indicating that a non-static assignment occurred (stored by the hoister).

Software	Version(s)
Parcel	ac5f1c1
Node
npm/Yarn
Operating System

[devongovett]

Hmm actually tracking this may be very difficult especially if the require result is assigned to the value of another variable or passed into a function. We may need to bail in any cases where the require is accessed non-statically, not just on assignments.