x/tools/go/vcs: package could provide an id of current working index

[krnowak]

Something like:

rr, _ := vcs.RepoRootForImportPath("github.com/golang/go", false)
fmt.Println("Current working change id:", rr.Cmd.GetId())

The GetId() function prototype could be func (v *Cmd) GetId() (string, error) and getting an id means:

1. git - git rev-parse HEAD
2. hg - hg id -i
3. bzr - bzr revno
4. svn - svnversion

The subversion here is an odd man out, which might be troublesome as the code in vcs package assumes that a command stored in Cmd member can provide all info.

My use case is creating container images from given project, so the created image could have a vcs info in its (JSON) metadata, for example git: 66199afb25487fd75bf870c72bc3cea33d95f89e

[dmitshur]

Thanks for the report. This package has been deprecated in #57051 and won't receive further development, so closing this as not planned.