x/tools/gopls: rebuilding golden tests fails

[pjweinb]

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

go version go1.16.2 darwin/amd64

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

go env Output

$ go env
GO111MODULE=""

GOARCH="amd64"

GOBIN=""

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

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

GOEXE=""

GOFLAGS=""

GOHOSTARCH="amd64"

GOHOSTOS="darwin"

GOINSECURE=""

GOMODCACHE="/Users/pjw/go/pkg/mod"

GONOPROXY=""

GONOSUMDB=""

GOOS="darwin"

GOPATH="/Users/pjw/go"

GOPRIVATE=""

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

GOROOT="/usr/local/go"

GOSUMDB="sum.golang.org"

GOTMPDIR=""

GOTOOLDIR="/usr/local/go/pkg/tool/darwin_amd64"

GOVCS=""

GOVERSION="go1.16.2"

GCCGO="gccgo"

AR="ar"

CC="clang"

CXX="clang++"

CGO_ENABLED="1"

GOMOD="/dev/null"

CGO_CFLAGS="-g -O2"

CGO_CPPFLAGS=""

CGO_CXXFLAGS="-g -O2"

CGO_FFLAGS="-g -O2"

CGO_LDFLAGS="-g -O2"

PKG_CONFIG="pkg-config"

GOGCCFLAGS="-fPIC -arch x86_64 -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/72/mj6w6gyj5dn6yp_2_tlbdwym00052r/T/go-build679490406=/tmp/go-build -gno-record-gcc-switches -fno-common"

What did you do?

Following the instructions in golang.org/x/tools/internal/lsp/tests/README.md, I executed

./internal/lsp/reset_golden.sh

What did you expect to see?

i expected no changes

What did you see instead?

	deleted:    internal/lsp/analysis/fillreturns/testdata/src/a/a.go.golden
	deleted:    internal/lsp/analysis/nonewvars/testdata/src/a/a.go.golden
	deleted:    internal/lsp/analysis/noresultvalues/testdata/src/a/a.go.golden
	deleted:    internal/lsp/analysis/simplifycompositelit/testdata/src/a/a.go.golden
	deleted:    internal/lsp/analysis/simplifyrange/testdata/src/a/a.go.golden
	deleted:    internal/lsp/analysis/simplifyslice/testdata/src/a/a.go.golden
	modified:   internal/lsp/testdata/godef/b/h.go.golden
	modified:   internal/lsp/testdata/signature/signature.go.golden
	modified:   internal/lsp/testdata/signature/signature_test.go.golden
	modified:   internal/lsp/testdata/snippets/literal.go.golden

Because of the deleted files the tests no longer pass. (The modified files don't affect test results.)

[ShoshinNikita]

Analyzer tests don't support rebuilding .golden files. So, the script just deletes .golden files under internal/lsp/analysis/. There are two possible solutions:

1. Don't remove .golden files for analyzer tests

   #!/bin/bash
   
   - find ./internal/lsp/ -name *.golden -delete
   + find ./internal/lsp/testdata/ -name *.golden -delete
   go test ./internal/lsp/source -golden
   go test ./internal/lsp/ -golden
   go test ./internal/lsp/cmd -golden

2. Add support for rebuilding .golden files for analyzer tests

---

There's also a new issue with rebuilding .golden files. Commit golang/tools@4c651fc added summary_generics.txt.golden. It is used when type parameters are enabled:

var summaryFile = "summary.txt"

func init() {
	if typeparams.Enabled {
		summaryFile = "summary_generics.txt"
	}
}

The problem is that we can't rebuild summary.txt.golden and summary_generics.txt.golden at the same time:

typeparams.Enabled	summary.txt.golden	summary_generics.txt.golden
false	rebuilt	removed
true	removed	rebuilt