cmd/vet/all: get golang.org/x/tools/go/analysis/cmd/vet via a go.mod file, not via coordinator

[bradfitz]

The cmd/vet/all program right now builds golang.org/x/tools/go/analysis/cmd/vet using the x/tools repo head tree places there by the x/build/cmd/coordinator.

Several problems with that, including:

• it doesn't work on release branches
• it's extra complication in the coordinator

It'd be nicer if cmd/vet/all just use modules mechanism & its versioning to get at x/tools/go/analysis/cmd/vet instead.

And then the coordinator could be simplified (https://golang.org/cl/169198).

/cc @dmitshur @bcmills @josharian

[gopherbot]

Change https://golang.org/cl/169198 mentions this issue: cmd/coordinator: remove special cases for misc-vet-vetall

[dmitshur]

cmd/vet/all is inside the cmd module, and its go.mod file specifies a version of the golang.org/x/tools module. Is it not being used?

go/src/cmd/go.mod

Line 11 in e6df179

golang.org/x/tools v0.0.0-20190320160634-b6b7807791df

[bradfitz]

Maybe! We could remove all the code in the coordinator for it and disable it on Go 1.12 and earlier release branches and see what happens.

[gopherbot]

Change https://golang.org/cl/169237 mentions this issue: cmd/vet/all: don't use the x/tools vet in GOPATH

[dmitshur]

And update the go.mod to latest code with the bug fixed.

FWIW, the x/tools version currently specified in the cmd module go.mod file predates both CL 168404 (which caused #30971) and CL 168803 (which fixed it), so it should pass.

When updating to a newer version, we should use golang/tools@6aabc1c or newer.

[gopherbot]

Change https://golang.org/cl/169239 mentions this issue: cmd: update go.mod versions for vetall bug

[gopherbot]

Change https://golang.org/cl/169339 mentions this issue: dashboard: only run misc-vet-vetall for master