x/tools/cmd/bundle: use caller's module version, not $GOPATH

[bradfitz]

There are two bundled packages in $GOROOT/src/net/http:

bradfitz@go:~/go/src/net/http$ git grep go:gener
h2_bundle.go://go:generate bundle -o h2_bundle.go -prefix http2 golang.org/x/net/http2
socks_bundle.go://go:generate bundle -o socks_bundle.go -dst net/http -prefix socks -underscore golang.org/x/net/internal/socks

A bundled package is a a package that gets fused in with another package to avoid an otherwise-circular dependency. (We can't just import golang.org/x/net/http2 from net/http as http2 implements interfaces using types in their signatures defined in net/http)

Currently, to update http2 in std you need to both update the go.mod+vendor files (for some of the http2 subpackages) as well as run the go generate bundle step to generate h2_bundle.go.

The bundle appears to just gets it code from whatever you have on your disk in $GOPATH, though. It should use the same version from the current module ($GOROOT/src/go.mod).

/cc @bcmills @jayconrod @alandonovan @dmitshur @ianlancetaylor

[gopherbot]

Change https://golang.org/cl/177037 mentions this issue: net/http: update vendored, bundled x/net/http2

[dmitshur]

bundle currently uses golang.org/x/tools/go/loader to load packages. At first glance, this issue is about making it use golang.org/x/tools/go/packages instead, which will make it support modules.

Added bundle to #24661.

/cc @ianthehat @matloob

[gopherbot]

Change https://golang.org/cl/189818 mentions this issue: cmd/bundle: use caller's module version via go/packages

[gopherbot]

Change https://golang.org/cl/189897 mentions this issue: src/go.mod: sync golang.org/x/net with h2_bundle.go

[gopherbot]

Change https://golang.org/cl/209901 mentions this issue: src/go.mod: sync golang.org/x/net with h2_bundle.go