snapcraft build <part> ignores the part

[Kyle Fazzari]

Using snapcraft v4.3:

$ snapcraft build part1
<snip>
Pulling part1
Pulling part2
Building part1
Building part2

I expect that to ONLY build "part1". Particularly given the help text:

$ snapcraft build --help
Usage: snapcraft build [OPTIONS] <part>...

  Build artifacts defined for a part.

  Examples:
      snapcraft build
      snapcraft build my-part1 my-part2
<snip>

[Sergio Schvezov (sergiusens)]

This seems to have never worked, while the CLI accepts these commands, the build provider's execute step only has step in its signature

[Kyle Fazzari (kyrofa)]

It certainly worked in v2, not sure when it broke in v3 (I only recently upgraded to v3 for my larger projects, so it makes sense that I'm discovering these things now).

[Chris Patterson (cjp256)]

Opened a PR to fix:
https://github.com/snapcore/snapcraft/pull/3572