If we encounter `go list` errors when loading a user's package, we
should try to see if they've encountered any of our common error cases.
They are: 1) a user has GO111MODULE=off, but is outside of their GOPATH,
and 2) a user is in module mode but doesn't have a go.mod file.
Fortunately, go/packages does a great job handling edge cases so gopls
will work well for most of them. The main issue will be unresolved
imports. These show up in DepErrors in `go list`, so go/packages doesn't
propagate them through to the list of errors. This will require changes
to go/packages.
Updates golang/go#31668
Change-Id: Ibd5253b33b38caffeaad54a403c74c0b861fcc14
Reviewed-on: https://go-review.googlesource.com/c/tools/+/194018
Run-TryBot: Rebecca Stambler <rstambler@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Cottrell <iancottrell@google.com>
