Karma finishes unexpectedly with no output?

[thepian]

Sorry in advance for a poor bug report.

I'm trying out the preprocessor and have it working without plugins, however it seems the rollup doesn't include the imports. I assume the Babel plugin is needed for things to work properly.

So I tried your example of adding rollup-plugin-babel, but when I do that the Karma server never takes off. There is no debug output, Karma just finishes.

Do you have any suggestions for how to debug this?

[thepian]

Actually I missed a cool part of rollup. Since I didn't refer to the imported source code it was removed ending up in a test without implementation. Once I referenced the source in a test it gets pulled in.

[klaascuvelier]

Glad you were able to resolve your own issue :) 👍

[danini-the-panini]

@thepian Hi, I seem to be getting the same issue as you. Karma is finishing with no output, however even if I reference the imported code it still does not work. I suspect it has something to do with the es2015 class syntax, as removing classes allows karma to run.

Here is a small example that reproduces my issue

// test/foo_test.js
import Foo from "../src/foo";

describe("foo", () => {
  it("bar", () => {
    assert.equal(new Foo().bar(), "baz");
  });
});

// src/foo.js

export default class Foo {
  bar() {
    return "baz";
  }
}

// karma.conf.js

module.exports = function(config) {
  config.set({
    basePath: "",
    frameworks: ["mocha", "chai"],
    files: [
      "test/**/*_test.js"
    ],
    preprocessors: {
      "test/**/*_test.js": ["rollup"]
    },
    exclude: [],
    rollupPreprocessor: {
      rollup: {
        plugins: [
          require("rollup-plugin-node-resolve")(),
          require("rollup-plugin-commonjs")({
            exclude: ["src/**", "test/**/*.js"]
          }),
          require("rollup-plugin-babel")({
            exclude: "node_modules/**",
            presets: [require("babel-preset-es2015-rollup")],
            babelrc: false
          })
        ]
      },
      bundle: {
        sourceMap: "inline"
      }
    },
    reporters: ["progress"],
    port: 9876,
    colors: true,
    logLevel: config.LOG_INFO,
    autoWatch: false,
    browsers: ["Chrome"],
    singleRun: true,
    concurrency: Infinity
  });
};

[jlmakes]

I noticed an invalid configuration (specifically an invalid moduleName) was causing the Karma to fail silently. I believe this would have been resolved by a try/catch around bundle.generate(), but in my recent testing with the latest version of Rollup — this no longer seems necessary.

Also @jellymann, I know I'm late to the party but the error you describe is surely related to this one... seems to have been an issue with the specific combination of plug-ins you listed:

• rollup-plugin-node-resolve
• rollup-plugin-commonjs
• rollup-plugin-babel

For what it's worth, I've had terrible luck combining Babel with Rollup... particularly in earlier versions of Node (where I suppose various ES2015 features aren't supported.)

Related #4