time.Parse("Jan 2, 2006", "Dec 4, 2019 11:14:25") returns an "extra text" error but does not even partially populate the time return value

[rbucker]

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

$ go version
1.16.2

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/rbucker/.cache/go-build"
GOENV="/home/rbucker/.config/go/env"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOINSECURE=""
GOMODCACHE="/home/rbucker/go/pkg/mod"
GONOPROXY=""
GONOSUMDB=""
GOOS="linux"
GOPATH="/home/rbucker/go"
GOPRIVATE=""
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/home/rbucker/bin/go"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/home/rbucker/bin/go/pkg/tool/linux_amd64"
GOVCS=""
GOVERSION="go1.16.2"
GCCGO="gccgo"
AR="gcc-ar"
CC="gcc"
CXX="g++"
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 -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build1925909121=/tmp/go-build -gno-record-gcc-switches"

What did you do?

time.Parse("Jan 2, 2006", "Dec 4, 2019 11:14:25")

https://play.golang.org/p/8RN0EnD2NMB

What did you expect to see?

I'm thinking about the OS file exists test where one has to test the err to determine what type of file... or something like that, however, it would be better if the time variable was filled with whatever had been collected to that point.

What did you see instead?

the default time value.

[ianlancetaylor]

I'm not sure what to say except: you're right. If time.Parse is unable to parse the date, then it returns an error and an empty time.Time value. That is how the function has worked since it was written, and changing it now would be more likely to introduce problems rather than fix them.