Wacky idea: Print a warning in go build (and friends) too. Lots of people have packages already checked out, so won't benefit from a go get warning alone.

If you want to check your package is depend on code.google.com, see https://github.com/mattn/check-code-google-com

What's the status here? It looks like the tool warns for some things but not others, and, e.g., oracle is just left broken on the old site:

maciek@mothra:~$ go get code.google.com/p/go.tools/cmd/oracle
# code.google.com/p/go.tools/cmd/oracle
../../../.gvm/pkgsets/go1.4/global/src/code.google.com/p/go.tools/cmd/oracle/main.go:166: too many arguments to conversion to oracle.Query: oracle.Query(args, mode, *posFlag, ptalog, &build.Default, *reflectFlag)

while godoc is nicer:

maciek@mothra:~$ go get code.google.com/p/go.tools/cmd/godoc
can't load package: the code.google.com/p/go.tools/cmd/godoc command has moved; use golang.org/x/tools/cmd/godoc instead.

Is that a server-side warning? In any case, it'd be great to provide warning; this would have saved me a few minutes tonight.

I don't think we should warn on go build. People with vendored code.google.com packages are fine as long as they don't update.

The bit about whether a package has moved is up to the package owner.

CL https://golang.org/cl/12070 mentions this issue.

CL https://golang.org/cl/18952 mentions this issue.

CL https://golang.org/cl/18974 mentions this issue.

CL https://golang.org/cl/21189 mentions this issue.