x/tools/gopls: version created by didChange ignored?

[myitcv]

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

$ go version
go version devel +3f21c2381d Thu Nov 14 01:57:00 2019 +0000 linux/amd64
$ go list -m golang.org/x/tools
golang.org/x/tools v0.0.0-20191113232020-e2727e816f5a
$ go list -m golang.org/x/tools/gopls
golang.org/x/tools/gopls v0.1.8-0.20191113232020-e2727e816f5a

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="on"
GOARCH="amd64"
GOBIN=""
GOCACHE="/home/myitcv/.cache/go-build"
GOENV="/home/myitcv/.config/go/env"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOINSECURE=""
GONOPROXY=""
GONOSUMDB=""
GOOS="linux"
GOPATH="/home/myitcv/gostuff"
GOPRIVATE=""
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/home/myitcv/gos"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/home/myitcv/gos/pkg/tool/linux_amd64"
GCCGO="gccgo"
AR="ar"
CC="gcc"
CXX="g++"
CGO_ENABLED="1"
GOMOD="/home/myitcv/gostuff/src/github.com/myitcv/govim/go.mod"
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-build713590986=/tmp/go-build -gno-record-gcc-switches"

What did you do?

govim has a test that verifies suggested fixes. The following file is opened in Vim:

package main

var x int

func main() {
	x = x
}

Because of a slight vagary of the test setup, the following sequence of events occurs with exactly the file contents above:

• didOpen with version 1
• didChange with version 2
• didChange with version 3

At this point therefore the current version of main.go is 3.

Then we trigger the code action:

&protocol.CodeActionParams{
    TextDocument: protocol.TextDocumentIdentifier{URI:"file:///tmp/go-test-script071826122/script-suggested_fixes/main.go"},
    Range:        protocol.Range{
        Start: protocol.Position{Line:5, Character:1},
        End:   protocol.Position{Line:5, Character:1},
    },
    Context: protocol.CodeActionContext{
        Diagnostics: {
            {
                Range: protocol.Range{
                    Start: protocol.Position{Line:5, Character:1},
                    End:   protocol.Position{Line:5, Character:1},
                },
                Severity:           2,
                Code:               nil,
                Source:             "assign",
                Message:            "self-assignment of x to x",
                Tags:               {1},
                RelatedInformation: nil,
            },
        },
        Only: {"quickfix"},
    },
    WorkDoneProgressParams: protocol.WorkDoneProgressParams{},
    PartialResultParams:    protocol.PartialResultParams{},
}

This gives us the following response:

[]protocol.CodeAction{
    {
        Title:       "Remove",
        Kind:        "quickfix",
        Diagnostics: {
            {
                Range: protocol.Range{
                    Start: protocol.Position{Line:5, Character:1},
                    End:   protocol.Position{Line:5, Character:1},
                },
                Severity:           2,
                Code:               nil,
                Source:             "assign",
                Message:            "self-assignment of x to x",
                Tags:               {1},
                RelatedInformation: nil,
            },
        },
        IsPreferred: false,
        Edit:        &protocol.WorkspaceEdit{
            Changes:         (*map[string][]protocol.TextEdit)(nil),
            DocumentChanges: {
                {
                    TextDocument: protocol.VersionedTextDocumentIdentifier{
                        Version:                1,
                        TextDocumentIdentifier: protocol.TextDocumentIdentifier{URI:"file:///tmp/go-test-script875975760/script-suggested_fixes/main.go"},
                    },
                    Edits: {
                        {
                            Range: protocol.Range{
                                Start: protocol.Position{Line:5, Character:1},
                                End:   protocol.Position{Line:5, Character:6},
                            },
                            NewText: "",
                        },
                    },
                },
            },
        },
        Command: (*protocol.Command)(nil),
    },
}

Notice however the version of the document change for main.go is version 1, not version 3.

What did you expect to see?

Version 3 in the document changes for main.go

What did you see instead?

Version 1.

Possibly related to #35114

gopls log file: fail.log

---

cc @stamblerre @ianthehat

[myitcv]

Closing for the same reasons described in #35114 (comment)