Go: x/build/cmd/release: go1.12rc1 source tarball includes empty gocache and tmp directories

[dmitshur]

Issue #29906 has been mostly resolved, but there's still a minor issue where the go1.12rc1.src.tar.gz release archive (from #30175) has empty gocache and tmp directories:

$ tree
.
├── go1.12rc1.src.tar.gz
└── go1.12rc1.src
    ├── go
    │   ├── AUTHORS
    │   ├── CONTRIBUTING.md
    │   ├── CONTRIBUTORS
    │   └── ...
    ├── gocache
    └── tmp

All other release archives do not have gocache and tmp directories.

These directories are empty, so the impact is low, but we should still clean this up further. /cc @bradfitz @FiloSottile @julieqiu @andybons

The source tarball also has a slightly different structure: it contains a top-level "go1.12rc1.src" directory, which then has a "go" directory inside. All others have "go" at the root. This isn't a problem, just mentioning it because it might be helpful for identifying the cause.

[bradfitz]

Sent https://go-review.googlesource.com/c/build/+/161967 (not sure what gopherbot is doing)

[gopherbot]

Change https://golang.org/cl/161967 mentions this issue: cmd/release: clean gocache and tmp in source mode too

[rsc]

This gets to be "Go1.12" not "Unreleased" because it affects the bits that go into the release (even though the command itself is not released).

[bradfitz]

The source tarball also has a slightly different structure: it contains a top-level "go1.12rc1.src" directory, which then has a "go" directory inside. All others have "go" at the root. This isn't a problem, just mentioning it because it might be helpful for identifying the cause.

I think the cause is you double clicking it on a Mac and macOS auto-extracting it using its prefix as the directory name. I don't see such a top-level directory actually existing:

bradfitz@gdev:~/src/golang.org/x/build/cmd/release$ curl --silent https://dl.google.com/go/go1.10.4.src.tar.gz | tar -zt | grep -v ^go/
bradfitz@gdev:~/src/golang.org/x/build/cmd/release$ curl --silent https://dl.google.com/go/go1.11.5.src.tar.gz | tar -zt | grep -v ^go/
gocache/
tmp/
bradfitz@gdev:~/src/golang.org/x/build/cmd/release$ curl --silent https://dl.google.com/go/go1.11.4.src.tar.gz | tar -zt | grep -v ^go/
bradfitz@gdev:~/src/golang.org/x/build/cmd/release$ 

[dmitshur]

@bradfitz You're absolutely right, that's what happened. I didn't know about that behavior of Archive Utility.app on macOS.

I also confirmed the "go" directory is indeed top-level in go1.12rc1.src.tar.gz by making quick use of the compress/gzip and archive/tar packages. Thanks for helping me understand this.