Missing options in examples

[jlmakes]

Missing options in examples

[jlmakes]

As I understand it, the options property is a common convention for preprocessors to distinguish between first-party and third-party configuration. I think a good example is the karma-typescript-preprocessor:

typescriptPreprocessor: {
	options: {
		sourceMap: false,
		target: 'ES5',
		module: 'amd',
		// etc...
	},
	transformPath(path) {
		return path.replace(/\.ts$/, '.js');
	}
}

The options property takes an object containing options to pass to the TypeScript compiler (third-party configuration).

Whereas other properties, transformPath in this case are, are for karma-typescript-preprocessor (first-party configuration).

[jlmakes]

We can see in the source how karma-rollup-preprocessor is designed:

karma-rollup-preprocessor/lib/index.js

Lines 19 to 22 in 9332a90

	const options = Object.assign({}, config.rollupPreprocessor, preconfig.options, {
	input: file.path,
	cache: cache.get(file.path),
	})

There is no expectation of an options property for normal preprocessor configurations… everything (i.e. config.rollupPreprocessor) is simply passed along to Rollup (with exception to input and cache being handled for you).

However when creating configured preprocessors, the preconfig.options property is used to distinguished between first and third party options as mentioned above.

...none of the plugins I specified were invoked. When I added options, it started working

It sounds like you were using a configured preprocessor. Otherwise, please share a reproduction.