time: Parse lacks Y10K support

[BenLubar]

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

$ go version
go version go1.12.5 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
GOARCH="amd64"
GOBIN="/home/ben/go/bin"
GOCACHE="/home/ben/.cache/go-build"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOOS="linux"
GOPATH="/home/ben/.golang-path:/home/ben/go"
GOPROXY=""
GORACE=""
GOROOT="/home/ben/.gimme/versions/go1.12.5.linux.amd64"
GOTMPDIR=""
GOTOOLDIR="/home/ben/.gimme/versions/go1.12.5.linux.amd64/pkg/tool/linux_amd64"
GCCGO="gccgo"
CC="gcc"
CXX="g++"
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 -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build930211599=/tmp/go-build -gno-record-gcc-switches"

What did you do?

https://play.golang.org/p/UKFjYzeIFA0

What did you expect to see?

10000-01-01
success 10000-01-01 00:00:00 +0000 UTC

What did you see instead?

10000-01-01
error parsing time "10000-01-01" as "2006-01-02": cannot parse "0-01-01" as "-"

[jamdagni86]

@ianlancetaylor the reason this is failing is the code expects years of length 4 (time/format.go:parse). fix is to look for the position of the first occurrence of hyphen instead of the hardcoded value (4). let me know if this needs to be fixed though.

[rsc]

We can probably put off trying to fix this until the year 9000. I'm confident 1000 years of lead time will be long enough. Please reopen or refile then. Thanks.

[BenLubar]

Alright, I will check back in 6981 years.

[rsc]

Thanks!