Locate-only plugins are broken/ignored in 0.20.5 (workaround provided)

[Rush]

Sample plugin:

// user for browserConfig only
// import pug files with "sample.pug!" when server is doing the compilation for ".pug.js" requests
exports.locate = function(load) {
  return Promise.resolve(load.address + '.js');
};

The result is being assigned here

systemjs/src/instantiate.js

Line 158 in f790864

metadata.pluginLoad.address = address;

But since the plugin does not have the fetch method it is then being ignored:

systemjs/src/instantiate.js

Line 167 in f790864

if (!metadata.pluginModule.fetch)

the provided load.address is only used when also .fetch is provided

systemjs/src/instantiate.js

Line 172 in f790864

return fetch(load.address, metadata.load.authorization, metadata.load.integrity, false);

[Rush]

A working workaround:

exports.fetch = function(load, origFetch) {
  return origFetch(load);
}

exports.locate = function(load) {
  return Promise.resolve(load.address + '.js');
};

[Rush]

Another issue, previously (in pre-0.20) it was possible to define a plugin without a promise:

exports.locate = function(load) {
  return load.address + '.js';
};

Would be nice to have it for compatibility.

[guybedford]

Thanks this would be a bug, will aim to fix this.

[guybedford]

Fixed in 7d47f1b.

[Rush]

@guybedford thanks. What about the first part of the issue where a plugin with .locate only is ignored?

[guybedford]

@Rush sure I've added a842efb.

[guybedford]

Released in 0.20.7.