x/tools/gopls: Diagnostic's CodeDescription field with empty href

[martskins]

go version:
    go version go1.15.2 darwin/amd64

go version -m (which gopls):
    /path/to/go/bin//gopls: go1.15.2
        path    golang.org/x/tools/gopls
        mod     golang.org/x/tools/gopls        v0.0.0-20201031021630-582c62ec74d0      h1:rkV8jMWGmZrVZYXGAWnw2J2dFwvwVqU6bYbd1bOJKNo=
        dep     github.com/BurntSushi/toml      v0.3.1  h1:WXkYYl6Yr3qBf1K79EBnL4mak0OimBfB0XUf9Vl28OQ=
        dep     github.com/google/go-cmp        v0.5.2  h1:X2ev0eStA3AbceY54o37/0PQ/UWqKEiiO2dKL5OPaFM=
        dep     github.com/sergi/go-diff        v1.1.0  h1:we8PVUC3FE2uYfodKH/nBHMSetSfHDR6scGdBi+erh0=
        dep     golang.org/x/mod        v0.3.0  h1:RM4zey1++hCTbCVQfnWeKs9/IEsaBLA8vTkd0WVtmH4=
        dep     golang.org/x/sync       v0.0.0-20201020160332-67f06af15bc9      h1:SQFwaSi55rU7vdNs9Yr0Z324VNlrF+0wMqRXT4St8ck=
        dep     golang.org/x/tools      v0.0.0-20201031021630-582c62ec74d0      h1:obBdJPIfkOi5/rVh102giHaq0G8BZGE4eGB+NU6SgBo=
        dep     golang.org/x/xerrors    v0.0.0-20200804184101-5ec99f83aff1      h1:go1bK/D/BFZV2I8cIQd1NKEZ+0owSTG1fDTci4IqFcE=
        dep     honnef.co/go/tools      v0.0.1-2020.1.6 h1:W18jzjh8mfPez+AwGLxmOImucz/IFjpNlrKVnaj2YVc=
        dep     mvdan.cc/gofumpt        v0.0.0-20201027171050-85d5401eb0f6      h1:QQ9mYdTscaVSaHC8A1wtLkECzvpD/YO2E2GyPvU1D/Y=
        dep     mvdan.cc/xurls/v2       v2.2.0  h1:NSZPykBXJFCetGZykLAxaL6SIpvbVy/UFEniIfHAa8A=

What did you do?

Open a file that had diagnostics to be reported. For example:

package main

func main() {
	var a = 42
}

What did you expect to see?

The diagnostics with either no codeDescription or a codeDescription with an href field and non-empty value.

What did you see instead?

Diagnostics with {"codeDescription": {"href": ""}}.

To add a little more context: I'm not sure if that's being marshaled that way intentionally, but I get the impression that it wasn't what was intended, given that there's an omitempty tag on the field (https://github.com/golang/tools/blob/8dabb740183dd603f671da47324972b578eaf158/internal/lsp/protocol/tsprotocol.go#L1140), but that field being a (non-pointer) struct will never be omitted. As it is being sent right now it breaks at least LanguageClientNeovim, as it fails to deserialize that into an URL, given that the value is an empty string.

[leitzler]

@gopherbot please add labels Tools, gopls

[leitzler]

cc @pjweinb

[pjweinb]

probably the right thing to do is to make Diagnostic.CodeDescription into a pointer. Let me look more closely.

[gopherbot]

Change https://golang.org/cl/267106 mentions this issue: internal/lsp: make Diagnostics.CodeDescription a pointer