proposal: cmd/go: force vendor directory only

[azr]

Hello there,

TLDR: it would be nice to be able to go build --using-vendors-only or something similar.

More thought:
I like a revision of a go project to be buildable.
Often when I update the vendors of a project, the ci tools tell me there is a missing dep or something is wrong with this or that dep, because that other pkg is outdated, because the system are different or other various reasons.
But it always works locally and then I find myself having a lot commits that contain fix godeps

So I'd like to have a pre commit hook that checks if the project builds in my ci.

that hook would do something like this: GOOS=linux go build --using-vendors-only

Tried GOOS=linux go build -pkgdir ./vendor but nope

[mvdan]

What about setting GOPATH to an empty directory?

[azr]

@mvdan empty default to $HOME and "/tmp" failed:

GOPATH=/tmp GOOS=linux go build ./cmd/runner
output:

 cannot find package "github.com/stvp/rollbar" in any of:
	/usr/local/opt/go/libexec/src/github.com/stvp/rollbar (from $GOROOT)
	/tmp/src/github.com/stvp/rollbar (from $GOPATH)

It doesn't look for the vendor dir, may be it should ?

And I can't use go build "project name/repo" because GOPATH is wrong.

Edit: same output for GOPATH=/tmp GOOS=linux go build -pkgdir ./vendor ./cmd/runner

[mvdan]

Ah right, it can't find any of the packages then. I guess you could set up a new GOPATH and link src/your/pkg to the right place, which should work as a script or shell alias. But that's not as simple.

Alternatively, I've seen discussions around "building Go packages outside of GOPATH". That might be a solution for this if you unset GOPATH, but it would probably be in the long term. I think that's #17271.

[vcabbage]

I agree that it would be useful to do this.

For the time being you could try https://github.com/cloudflare/hellogopher. The Makefile creates a .GOPATH directory within your project and uses that for tests, building, etc.

[azr]

@vcabbage works like a charm, thanks

[rtuin]

I think this is a great idea. Being able to build (dependencies) in an isolated environment reduces frustration and increases software stability. 👍

[rsc]

On hold for package management. We'll get there but vendor may or may not be the answer.

[bcmills]

I think this is -mod=vendor in module mode.
(Can this proposal be closed as completed?)