testing: T.Setenv can be called after T.Parallel #55128
Description
What version of Go are you using (go version)?
$ go version go version go1.19.1 linux/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="$HOME/.cache/go-build" GOENV="$HOME/.config/go/env" GOEXE="" GOEXPERIMENT="" GOFLAGS="" GOHOSTARCH="amd64" GOHOSTOS="linux" GOINSECURE="" GOMODCACHE="$HOME/go/pkg/mod" GONOPROXY="" GONOSUMDB="" GOOS="linux" GOPATH="$HOME/go" GOPRIVATE="" GOPROXY="https://proxy.golang.org,direct" GOROOT="/usr/local/go" GOSUMDB="sum.golang.org" GOTMPDIR="" GOTOOLDIR="/usr/local/go/pkg/tool/linux_amd64" GOVCS="" GOVERSION="go1.19.1" GCCGO="gccgo" GOAMD64="v1" AR="ar" CC="gcc" CXX="g++" CGO_ENABLED="1" GOMOD="$HOME/dev/go.mod" GOWORK="" 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 -Wl,--no-gc-sections -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build1463438795=/tmp/go-build -gno-record-gcc-switches"
What did you do?
T.Setenv will panic if it be called after T.Parallel but it can be called in T.Run.
Sample code:
https://go.dev/play/p/54VhJKYpb_q
What did you expect to see?
I think it should panic even in T.Run.
What did you see instead?
Those tests become flaky without panic.
Others
I'm trying to fix this issue now.