x/tools/cmd/goimports: GOPATH not honored with absolute file paths

[akavel]

Please answer these questions before submitting your issue. Thanks!

1. What version of Go are you using (go version)?

go version go1.5.4 linux/amd64

1. What operating system and processor architecture are you using (go env)?

GOARCH="amd64"
GOBIN=""
GOEXE=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOOS="linux"
GOPATH="/home/akavel/gopath/src/zpaslab.com/lockerbox/_vendor:/home/akavel/gopath"
GORACE=""
GOROOT="/home/akavel/go"
GOTOOLDIR="/home/akavel/go/pkg/tool/linux_amd64"
GO15VENDOREXPERIMENT=""
CC="gcc"
GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0"
CXX="g++"
CGO_ENABLED="1"

1. What did you do?
   If possible, provide a recipe for reproducing the error.
   A complete runnable program is good.
   A link on play.golang.org is best.

I've upgraded goimports, following the recent "it's now faster" announcement. I retained the old binary, and now I have 2 binaries:

$ LC_ALL=C ll ~/gopath/bin/goimports*
-rwxr-xr-x 1 akavel akavel 5509320 Jul 21 13:59 /home/akavel/gopath/bin/goimports*
-rwxr-xr-x 1 akavel akavel 5323816 Apr 27 14:49 /home/akavel/gopath/bin/goimports.old1*
-rwxr-xr-x 1 akavel akavel 5509320 Jul 21 13:59 /home/akavel/gopath/bin/goimports.old2*
$ LC_ALL=C date -Isec
2016-07-21T14:21:05+0200                                            

Depending whether I run the new one with relative or absolute path to source file, import gets found or not:

$ goimports.old2 /home/akavel/gopath/src/zpaslab.com/lockerbox/overmind/collector_rest_test.go | grep protobuf
$ goimports.old1 /home/akavel/gopath/src/zpaslab.com/lockerbox/overmind/collector_rest_test.go | grep protobuf
        "github.com/golang/protobuf/proto"
$ goimports.old2 ./overmind/collector_rest_test.go | grep protobuf
        "github.com/golang/protobuf/proto"
$ goimports.old1 ./overmind/collector_rest_test.go | grep protobuf
        "github.com/golang/protobuf/proto"

Additional notes:

• exactly the same behavior happens for packages not in _vendor/, e.g. "zpaslab.com/lockerbox/db"
• standard library packages are found OK (e.g. "testing")
• the same seems to happen when using -srcdir (i.e. in vim-go)

1. What did you expect to see?

All versions would find the import:

$ goimports.old2 /home/akavel/gopath/src/zpaslab.com/lockerbox/overmind/collector_rest_test.go | grep protobuf
        "github.com/golang/protobuf/proto"
$ goimports.old1 /home/akavel/gopath/src/zpaslab.com/lockerbox/overmind/collector_rest_test.go | grep protobuf
        "github.com/golang/protobuf/proto"
$ goimports.old2 ./overmind/collector_rest_test.go | grep protobuf
        "github.com/golang/protobuf/proto"
$ goimports.old1 ./overmind/collector_rest_test.go | grep protobuf
        "github.com/golang/protobuf/proto"

1. What did you see instead?

$ goimports.old2 /home/akavel/gopath/src/zpaslab.com/lockerbox/overmind/collector_rest_test.go | grep protobuf
$ goimports.old1 /home/akavel/gopath/src/zpaslab.com/lockerbox/overmind/collector_rest_test.go | grep protobuf
        "github.com/golang/protobuf/proto"
$ goimports.old2 ./overmind/collector_rest_test.go | grep protobuf
        "github.com/golang/protobuf/proto"
$ goimports.old1 ./overmind/collector_rest_test.go | grep protobuf
        "github.com/golang/protobuf/proto"

[bradfitz]

What does the -v flag to goimports.old2 say with an absolute path?

$ goimports.old2 -v /home/akavel/gopath/src/zpaslab.com/lockerbox/overmind/collector_rest_test.go

And can you diff the -v output between the absolute and relative path mode and include that too?

[stapelberg]

I’m facing the same issue.

git bisect identifies commit golang/tools@e047ae7 as the first bad commit

Unfortunately, the previous commit does not have the -v flag, so I can’t provide the output you’ve asked for.

However, while collecting the steps to reproduce, I think I figured out what caused the issue for me:

$ go env GOPATH GOROOT
/home/michael/gocode
/home/michael/go

The following change makes goimports work again in my setup:

diff --git i/imports/fix.go w/imports/fix.go
index 4d7dfeb..ca721e0 100644
--- i/imports/fix.go
+++ w/imports/fix.go
@@ -661,7 +661,7 @@ func findImportGoPath(pkgName string, symbols map[string]bool, filename string)
        // TODO(bradfitz): run each $GOPATH entry async. But nobody
        // really has more than one anyway, so low priority.
        scanGoRootOnce.Do(scanGoRoot) // async
-       if !strings.HasPrefix(filename, build.Default.GOROOT) {
+       if !strings.HasPrefix(filename, build.Default.GOROOT+"/") {
                scanGoPathOnce.Do(scanGoPath) // blocking
        }
        <-scanGoRootDone

[bradfitz]

@stapelberg, thanks for the clue. I sent out https://golang.org/cl/25192. Feel free to review.

[gopherbot]

CL https://golang.org/cl/25192 mentions this issue.

[akavel]

the CL fixes it, thanks guys! (i.e. works correctly in vim-go now)