Plotter crashes and burns on stroke with non-existent tool

[ju5t]

I ran into a problem today and for some reason I can't seem to try {} catch {} my way out of it. I get the following error when trying to parse gerber files that were created with Vutrax.

/usr/local/lib/node_modules/gerber-to-svg/node_modules/gerber-plotter/lib/_operate.js:358
  if (!region && (tool.trace.length === 0)) {
                       ^

TypeError: Cannot read property 'trace' of null
    at interpolate (/usr/local/lib/node_modules/gerber-to-svg/node_modules/gerber-plotter/lib/_operate.js:358:24)
    at operate (/usr/local/lib/node_modules/gerber-to-svg/node_modules/gerber-plotter/lib/_operate.js:405:13)
    at Plotter._transform (/usr/local/lib/node_modules/gerber-to-svg/node_modules/gerber-plotter/lib/plotter.js:177:18)
    at Plotter.Transform._read (/usr/local/lib/node_modules/gerber-to-svg/node_modules/readable-stream/lib/_stream_transform.js:184:10)
    at Plotter.Transform._write (/usr/local/lib/node_modules/gerber-to-svg/node_modules/readable-stream/lib/_stream_transform.js:172:83)
    at doWrite (/usr/local/lib/node_modules/gerber-to-svg/node_modules/readable-stream/lib/_stream_writable.js:418:64)
    at writeOrBuffer (/usr/local/lib/node_modules/gerber-to-svg/node_modules/readable-stream/lib/_stream_writable.js:407:5)
    at Plotter.Writable.write (/usr/local/lib/node_modules/gerber-to-svg/node_modules/readable-stream/lib/_stream_writable.js:334:11)
    at Parser.ondata (/usr/local/lib/node_modules/gerber-to-svg/node_modules/readable-stream/lib/_stream_readable.js:619:20)
    at Parser.emit (events.js:180:13)

@mcous I can send you the gerber files via e-mail if that helps.

[mcous]

@ju5t that's pretty odd. Gerber file would be super helpful if available

[mcous]

@ju5t turns out this is a bug in plotter exposed by a bug in the parser which is actually causing your problems: mcous/gerber-parser#23. TL;DR: gerber-parser thinks your Gerber files are drill files because they start with a newline.

As a workaround until the parser is fixed, you could look into passing the filetype option to gerber-to-svg to force the parser to use the correct type. Assuming whats-that-gerber is already involved, you could probably get away with something like:

const whatsThatGerber = require('whats-that-gerber')
const gerberToSvg = require('gerber-to-svg')
// ...
const filename = getFilenameSomehow()
const layerType = whatsThatGerber(filename)
// ...
const converter = gerberToSvg(fs.createReadStream(filename), {
  id: getIdSomehow(),
  filetype: (layerType === 'drl') ? 'drill' : 'gerber'
})
// ...

[ju5t]

Got it. I don't think it'll be that easy for us to implement the workaround because we're using pcb-stackup in our project. It's not a major problem, I'll figure out how to catch it for now so we can display a user friendly error.

[mcous]

@ju5t pcb-stackup still has the ability to pass options into gerber-to-svg

const fs = require('fs')
const pcbStackup = require('pcb-stackup')
const whatsThatGerber = require('whats-that-gerber')
const shortId = require('shortid')

const fileNames = [
  '/path/to/board-F.Cu.gtl',
  '/path/to/board-F.Mask.gts',
  '/path/to/board-F.SilkS.gto',
  '/path/to/board-F.Paste.gtp',
  '/path/to/board-B.Cu.gbl',
  '/path/to/board-B.Mask.gbs',
  '/path/to/board-B.SilkS.gbo',
  '/path/to/board-B.Paste.gbp',
  '/path/to/board-Edge.Cuts.gm1',
  '/path/to/board.drl',
  '/path/to/board-NPTH.drl',
]

const layers = fileNames.map(filename => ({
  filename,
  gerber: fs.createReadStream(path),
  options: {
    id: shortId.generate()
    filetype: (layerType === 'drl') ? 'drill' : 'gerber'
  }
}))

pcbStackup(layers, (error, stackup) => {
  if (error) return console.error(error)

  console.log(stackup.top.svg) // logs "<svg ... </svg>"
  console.log(stackup.bottom.svg) // logs "<svg ... </svg>"
})

[ju5t]

@mcous thanks for the example. I've tested the workaround locally and that works.

[mcous]

Closing in favor of tracespace/tracespace#83