fileSet in engine plugin undefined

[Circlebit]

I'm just getting started with unified and tried to run the example code for engine plugins from here.

Unfortunately it won't work because in the plugin function the parameter set is undefined.

My understanding is, that it should contain a fileSet at this point. Can somebody help / explain?

[wooorm]

It should be a set if you follow the example strictly.
But that means that you are using the engine.
Are you using the engine?
Did you change the example?

[Circlebit]

My goal is to learn how to use the engine.
I pasted the example into index.js of an empty module (see here)

running node index.js returns this error:

readme.md
  1:1  error  TypeError: Cannot read properties of undefined (reading 'use')
    at Function.plugin (file:///Users/paul/Labor/unified-engine-example/index.js:21:7)
    at Function.freeze (file:///Users/paul/Labor/unified-engine-example/node_modules/unified/lib/index.js:136:36)
    at Function.parse (file:///Users/paul/Labor/unified-engine-example/node_modules/unified/lib/index.js:262:15)
    at parse (file:///Users/paul/Labor/unified-engine-example/node_modules/unified-engine/lib/file-pipeline/parse.js:50:36)
    at wrapped (file:///Users/paul/Labor/unified-engine-example/node_modules/trough/index.js:115:27)
    at next (file:///Users/paul/Labor/unified-engine-example/node_modules/trough/index.js:65:23)
    at done (file:///Users/paul/Labor/unified-engine-example/node_modules/trough/index.js:148:7)
    at file:///Users/paul/Labor/unified-engine-example/node_modules/unified-engine/lib/file-pipeline/read.js:42:7
    at FSReqCallback.readFileAfterClose [as oncomplete] (node:internal/fs/read_file_context:68:3)

✖ 1 error

[wooorm]

Ah, something changed years ago and didn’t make it in that example:

function plugin(processor, options, set) {

->

function plugin(options, set) {
  // `this` is now `processor`, if needed.

[wooorm]

Fixed: unifiedjs/unified-engine@cea793e.

Though, file sets aren’t very useful. You almost never need them. So I am not sure why you’re interested in them.