x/tools/gopls: gopls ignores the fact that the client doesn't support hierarchicalDocumentSymbolSupport

[edkolev]

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

$ go version

go version go1.13.1 darwin/amd64

Does this issue reproduce with the latest release?

Yes.

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

go env Output

$ go env
GO111MODULE=""

GOARCH="amd64"

GOBIN=""

GOCACHE="/Users/edkolev/Library/Caches/go-build"

GOENV="/Users/edkolev/Library/Application Support/go/env"

GOEXE=""

GOFLAGS=""

GOHOSTARCH="amd64"

GOHOSTOS="darwin"

GONOPROXY=""

GONOSUMDB=""

GOOS="darwin"

GOPATH="/Users/edkolev/gocode"

GOPRIVATE=""

GOPROXY="https://proxy.golang.org,direct"

GOROOT="/usr/local/Cellar/go/1.13.1/libexec"

GOSUMDB="sum.golang.org"

GOTMPDIR=""

GOTOOLDIR="/usr/local/Cellar/go/1.13.1/libexec/pkg/tool/darwin_amd64"

GCCGO="gccgo"

AR="ar"

CC="clang"

CXX="clang++"

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 -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/v7/fnkk7zpd0hvdsl45hpj92cc40000gn/T/go-build203896190=/tmp/go-build -gno-record-gcc-switches -fno-common"

What did you do?

1. Start emacs, install eglot LSP client
2. Open a main.go with contents

package main

func main() {
	print("hello")
}

3. Run M-x eglot. At this point eglot notifies gopls for its capabilities as a client. Note that it doesn't report hierarchicalDocumentSymbolSupport as supported.

:capabilities
                      (:workspace
                       (:applyEdit t :executeCommand
                                   (:dynamicRegistration :json-false)
                                   :workspaceEdit
                                   (:documentChanges :json-false)
                                   :didChangeWatchedFiles
                                   (:dynamicRegistration t)
                                   :symbol
                                   (:dynamicRegistration :json-false))
                       :textDocument
                       (:synchronization
                        (:dynamicRegistration :json-false :willSave t :willSaveWaitUntil t :didSave t)
                        :completion
                        (:dynamicRegistration :json-false :completionItem
                                              (:snippetSupport t)
                                              :contextSupport t)
                        :hover
                        (:dynamicRegistration :json-false)
                        :signatureHelp
                        (:dynamicRegistration :json-false :signatureInformation
                                              (:parameterInformation
                                               (:labelOffsetSupport t)))
                        :references
                        (:dynamicRegistration :json-false)
                        :definition
                        (:dynamicRegistration :json-false)
                        :documentSymbol
                        (:dynamicRegistration :json-false :symbolKind
                                              (:valueSet
                                               [1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26]))
                        :documentHighlight
                        (:dynamicRegistration :json-false)
                        :codeAction
                        (:dynamicRegistration :json-false :codeActionLiteralSupport
                                              (:codeActionKind
                                               (:valueSet
                                                ["quickfix" "refactor" "refactor.extract" "refactor.inline" "refactor.rewrite" "source" "source.organizeImports"])))
                        :formatting
                        (:dynamicRegistration :json-false)
                        :rangeFormatting
                        (:dynamicRegistration :json-false)
                        :rename
                        (:dynamicRegistration :json-false)
                        :publishDiagnostics
                        (:relatedInformation :json-false))
                       :experimental nil)

4. Run M-x imenu which causes the following communication, note that gopls replies with a hierarchical document symbol response.

client-request (id:4) Sat Oct 12 11:59:33 2019:
(:jsonrpc "2.0" :id 4 :method "textDocument/documentSymbol" :params
          (:textDocument
           (:uri "file:///Users/edkolev/dev/go-play/main.go")))

server-reply (id:4) Sat Oct 12 11:59:33 2019:
(:jsonrpc "2.0" :result
          [(:name "main" :detail "()" :kind 12 :range
                  (:start
                   (:line 2 :character 0)
                   :end
                   (:line 4 :character 1))
                  :selectionRange
                  (:start
                   (:line 2 :character 5)
                   :end
                   (:line 2 :character 9)))]
          :id 4)

5. Emacs shows an error

What did you expect to see?

The list of symbols in the main.go file, i.e. the main() function.

What did you see instead?

Emacs error.

Notes

• this issue has been reported in eglot here joaotavora/eglot#317
• there's an open PR in eglot to add support for hierarchical response to textDocument/documentSymbol joaotavora/eglot#303

[ysz]

Claimed! :-)