Added support for excellon drill files w/ leading/trailing set in M71/M72 line

[davidworkman9]

Ran into a drill file recently that started off like this:

M48
M72,LZ

I don't know that this is official syntax, but this adds support for files like it.

Note this is completely untested. I started writing tests, but couldn't figure out how to get them to run. It appears there's a bunch of unmarked dependencies required to get a test environment working.

[mcous]

Thanks @davidworkman9, this looks like a good change. M71 and M72 are listed as valid inch and metric commands in this archived version of the Excellon "spec".

As for tests, it looks like a sub-dependency was unpublished from npm for some reason, so CI is broken because that version doesn't exist in the lockfile. I'll need to fix that up, and I'll ping you here once it's done so you can rebase. Sorry for the inconvenience.

Once that's fixed, make sure you're in the repository root and do:

npm install
npm test

(Same instructions as in the "contributing" section of the readme)

[mcous]

CI job was fixed with #97. I'd recommend rebasing your branch and giving tests another shot!

[mcous]

@davidworkman9 were you able to make any progress on rebasing?

[codecov]

Codecov Report

Merging #96 into next will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##             next      #96   +/-   ##
=======================================
  Coverage   94.26%   94.26%           
=======================================
  Files          49       49           
  Lines        2058     2058           
=======================================
  Hits         1940     1940           
  Misses        118      118

Impacted Files	Coverage Δ
packages/gerber-parser/lib/_parse-drill.js	100% <100%> (ø)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 2adf8ca...03a3985. Read the comment docs.

[davidworkman9]

Thanks @mcous I was able to get a test environment running after rebasing.

[mcous]

Thanks for the PR! This looks great

[mcous]

Released as:

• @tracespace/cli: 4.0.0-next.17
• gerber-parser: 4.0.0-next.17
• gerber-to-svg: 4.0.0-next.17
• pcb-stackup: 4.0.0-next.17

[davidworkman9]

Thanks @mcous !