test(run): add test broken in the latest rollup

[TrySound]

#192 Rollup Plugin Name: run

This PR contains:

• bugfix
• feature
• refactor
• documentation
• other

Are tests included?

• yes (bugfixes and features will not be merged without tests)
• no

Breaking Changes?

• yes (breaking changes will not be merged unless absolutely necessary)
• no

List any relevant issue numbers:

Description

I found case where new rollup fails with run plugin.
When entry point and dynamic import use the same module
chunk.modules becomes empty. Run checks chunk.modules[input] for some
reason which fails when chunk.modules is empty.

@lukastaegert could you take a look?

[TrySound]

@lukastaegert I guess this happens because of circular dependencies. This is a tradeoff of reusing stuff in dynamic chunks. Would be good to have a warning for such cases. I didn't found any in my circular dependencies warnings though I could miss it because I have ~100 in graphql server.

[shellscape]

@TrySound a few CI issues to clear up there.

[lukastaegert]

This does not always work and was already broken before Rollup 2: https://github.com/rollup/plugins/blob/master/packages/run/lib/index.js#L52-L55

The point is that when Rollup cannot match the export signature of an entry chunk because it needs to add additional exports, it will create a facade chunk that reexports exactly those exports that the original entry point exposed. A facade chunk will have its chunk.modules empty because it does not contain the code of any module, it just contains reexports.

However you can use the facadeModuleId to achieve what you want.

Also note that if a plugin just wants to read options, it should NOT use the options hook because other plugins can still mutate options at that point. If you just want to read, always use buildStart which receives the final options used by Rollup. Here is a proposal how you could rewrite the plugin to make it work:

const path = require('path');
const childProcess = require('child_process');

module.exports = (opts = {}) => {
  let input;
  let proc;

  const args = opts.args || [];
  const forkOptions = opts.options || opts;
  delete forkOptions.args;

  return {
    name: 'run',

    // As stated above, do not use options here
    buildStart(opts) {
      let inputs = opts.input;

      if (typeof inputs === 'string') {
        inputs = [inputs];
      }

      if (typeof inputs === 'object') {
        inputs = Object.values(inputs);
      }

      if (inputs.length > 1) {
        throw new Error(`@rollup/plugin-run only works with a single entry point`);
      }

      input = path.resolve(inputs[0]);
    },

    generateBundle(outputOptions, bundle, isWrite) {
      if (!isWrite) {
        this.error(`@rollup/plugin-run currently only works with bundles that are written to disk`);
      }
    },

    writeBundle(outputOptions, bundle) {
      const dir = outputOptions.dir || path.dirname(outputOptions.file);
      const entryFileName = Object.keys(bundle)
        .find(fileName => bundle[fileName].facadeModuleId === input);

      if (entryFileName) {
        if (proc) proc.kill();
        proc = childProcess.fork(path.join(dir, entryFileName), args, forkOptions);
      } else {
        this.error(`@rollup/plugin-run could not find output chunk`);
      }
    }
  };
};

[TrySound]

Awesome! Thanks for response @lukastaegert. I'll try to cover all cases with tests.