0.15.22 regression: external requires are mapped to the main file

[adamburgess]

input file: app.js

import React from 'react'
console.log(React);

0.15.21 build to cjs with react as external: jspm build app.js --format cjs --externals react

'use strict';
Object.defineProperty(exports, '__esModule', { value: true });
function _interopDefault (ex) { return (ex && (typeof ex === 'object') && 'default' in ex) ? ex['default'] : ex; }

var React = _interopDefault(require('react'));
console.log(React);
//# sourceMappingURL=build.js.map

As you can see, it require's react, as expected.

0.15.22 build to cjs with react as external: jspm build app.js --format cjs --externals react

'use strict';
Object.defineProperty(exports, '__esModule', { value: true });
function _interopDefault (ex) { return (ex && (typeof ex === 'object') && 'default' in ex) ? ex['default'] : ex; }

var React = _interopDefault(require('react/react.js'));
console.log(React);
//# sourceMappingURL=build.js.map

Here it erroneously require's react/react.js.

The bug is still there in 0.15.23.

[adamburgess]

so the fix in eabc810 wasn't perfect, it seems

[guybedford]

@adamburgess right, we should extend the function getAlias to do package detection and remove mains at https://github.com/systemjs/builder/blob/master/lib/utils.js#L77 before running the reverse map configuration.

The package lookup is provided at https://github.com/systemjs/builder/blob/master/lib/utils.js#L302 so this should be as simple as something like:

var packageName = getPackage(loader.packages, loader.decanonicalize(canonicalName));
var packageMain = packageName && loader.packages[packageName].main;
if (packageMain && canonicalName.substr(canonicalName.length - packageMain.length - 1) == '/' + packageMain)
  canonicalName = canonicalName.substr(0, canonicalName.length - packageMain.length - 1);

[guybedford]

Added in 5e72725.

[guybedford]

Released in 0.15.24.