x/tools/internal/lsp: gopls hangs on a testdata workspace

[bstaletic]

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

$ go version
go version go1.12.1 linux/amd64

Does this issue reproduce with the latest release?

Yes, I am using the latest go release.

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

go env Output

$ go env
GOARCH="amd64"
GOBIN=""
GOCACHE="/home/bstaletic/.cache/go-build"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOOS="linux"
GOPATH="/home/bstaletic/Temp/ycmd/test"
GOPROXY=""
GORACE=""
GOROOT="/usr/lib/go"
GOTMPDIR=""
GOTOOLDIR="/usr/lib/go/pkg/tool/linux_amd64"
GCCGO="gccgo"
CC="gcc"
CXX="g++"
CGO_ENABLED="1"
GOMOD=""
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build983012561=/tmp/go-build -gno-record-gcc-switches"

This was also reproduced on Windows.

What did you do?

I am one of the maintainers of ycmd and we wanted to switch from gocode to gopls, however gopls doesn't respond to any requests.

Unfortunately that means the steps to reproduce need to contain instruction on setting up ycmd.

Steps to reproduce:

• Since ycmd can be used with different editors, I'm going to assume vim.
• git clone https://github.com/Valloric/YouComplete (use your vim plugin manager)
• cd YouCompleteMe
• git submodule update --init --recursive
• cd third_party/ycmd
• git remote add bstaletic https://github.com/bstaletic/ycmd && git fetch bstaletic
• git checkout bstaletic/gopls
• ./build.py --go-completer
• vim foo.go
• Type :YcmCompleter GoTo (or any other :YcmCompleter command)
  • Result: vim hangs until ycmd reports "request timed out"
• Enter insert mode and press <C-Space> (should display gopls's completion results)
  • Result: Nothing happens.

What did you expect to see?

GOPLS providing completions and other advertised capabilities.

What did you see instead?

Request timeouts and editor hangs.

GOPLS and ycmd logs: https://gist.github.com/bstaletic/57ac9351b356c9266391bcc477f865b4

[stamblerre]

@bstaletic: do you mind syncing to head and trying again? I broke gopls for about an hour today, and I'm wondering if you maybe just synced to a bad CL. I followed your repro instructions, and it worked for me.

[bstaletic]

Thanks for looking into this. I have pulled in the latest master and now I do get a response, but it's always the same error.

From ycmd log:

2019-04-02 02:41:30,522 - DEBUG - TX: Sending message: b'Content-Length: 255\r\n\r\n{"id": "2", "jsonrpc": "2.0", "method": "textDocument/definition", "params": {"position": {"character": 1, "line": 8}, "textDocument": {"uri": "file:///home/bstaletic/.vim/pack/bundle/start/YouCompleteMe/third_party/ycmd/ycmd/tests/go/testdata/test.go"}}}'
2019-04-02 02:41:30,547 - DEBUG - RX: Received message: b'{"jsonrpc":"2.0","error":{"code":0,"message":"no file information for file:///home/bstaletic/.vim/pack/bundle/start/YouCompleteMe/third_party/ycmd/ycmd/tests/go/testdata/test.go","data":null},"id":"2"}'
Traceback (most recent call last):
  File "/home/bstaletic/.vim/pack/bundle/start/YouCompleteMe/third_party/ycmd/third_party/bottle/bottle.py", line 862, in _handle
    return route.call(**args)
  File "/home/bstaletic/.vim/pack/bundle/start/YouCompleteMe/third_party/ycmd/third_party/bottle/bottle.py", line 1740, in wrapper
    rv = callback(*a, **ka)
  File "/home/bstaletic/.vim/pack/bundle/start/YouCompleteMe/third_party/ycmd/ycmd/watchdog_plugin.py", line 104, in wrapper
    return callback( *args, **kwargs )
  File "/home/bstaletic/.vim/pack/bundle/start/YouCompleteMe/third_party/ycmd/ycmd/hmac_plugin.py", line 68, in wrapper
    body = callback( *args, **kwargs )
  File "/home/bstaletic/.vim/pack/bundle/start/YouCompleteMe/third_party/ycmd/ycmd/handlers.py", line 82, in RunCompleterCommand
    request_data ) )
  File "/home/bstaletic/.vim/pack/bundle/start/YouCompleteMe/third_party/ycmd/ycmd/completers/completer.py", line 350, in OnUserCommand
    return command( self, request_data, arguments[ 1: ] )
  File "/home/bstaletic/.vim/pack/bundle/start/YouCompleteMe/third_party/ycmd/ycmd/completers/language_server/language_server_completer.py", line 54, in <lambda>
    lambda self, request_data, args: self.GoTo( request_data, [ 'Definition' ] )
  File "/home/bstaletic/.vim/pack/bundle/start/YouCompleteMe/third_party/ycmd/ycmd/completers/language_server/language_server_completer.py", line 1657, in GoTo
    result = self._GoToRequest( request_data, handlers[ 0 ] )
  File "/home/bstaletic/.vim/pack/bundle/start/YouCompleteMe/third_party/ycmd/ycmd/completers/language_server/language_server_completer.py", line 1638, in _GoToRequest
    REQUEST_TIMEOUT_COMMAND )[ 'result' ]
  File "/home/bstaletic/.vim/pack/bundle/start/YouCompleteMe/third_party/ycmd/ycmd/completers/language_server/language_server_completer.py", line 387, in GetResponse
    return response.AwaitResponse( timeout )
  File "/home/bstaletic/.vim/pack/bundle/start/YouCompleteMe/third_party/ycmd/ycmd/completers/language_server/language_server_completer.py", line 195, in AwaitResponse
    error.get( 'message' ) or 'No message' ) )
ycmd.completers.language_server.language_server_completer.ResponseFailedException: Request failed: 0: no file information for file:///home/bstaletic/.vim/pack/bundle/start/YouCompleteMe/third_party/ycmd/ycmd/tests/go/testdata/test.go

Unfortunately the gopls log is completely empty. Currently on commit:

4c644d7e (HEAD -> master, origin/master, origin/HEAD) internal/lsp: avoid extra work in *cache.View.remove

[stamblerre]

Oh right, forgot that you were in a testdata directory. go list specifically ignores testdata files, so gopls doesn't work on them. Can you try it in another file?

[bstaletic]

I wish it was that easy. Exactly the same behaviour for file:///home/bstaletic/foo.go - no log and Request failed: 0: no file information for <any URI>.

[stamblerre]

are you using $GOPATH or go modules?

[stamblerre]

to get a log, you will want to pass the -logfile flag.

[bstaletic]

are you using $GOPATH or go modules?

I tried with and without $GOPATH and no module. When I had $GOPATH set, it was set to the same directory that was used for gopls installation, which ends up being ycmd/third_party/go.

to get a log, you will want to pass the -logfile flag.

Even with that flag, the log was 0 bytes.

[stamblerre]

If you're not using Go modules, you will need to have $GOPATH configured correctly. Did the ycmd/third_party/go directory have the expected $GOPATH layout with the src, bin, and pkg directories in it?

[bstaletic]

ycmd/third_party/go does have src and bin, but there's no pkg, but even if I create ycmd/third_party/go/pkg I still get the "no file information" error.

[stamblerre]

What is the path of the file you are testing on. Is it also in $GOPATH/src? file:///home/bstaletic/foo.go doesn't appear to be.

[bstaletic]

Ahhh! So that was the problem! golsp works inside $GOPATH. Thanks for helping me figure this out.

[stamblerre]

No problem! Glad it's working.