time: LoadLocation: ZONEINFO variable without effect on Windows

[geoko86]

When you try to execute time.LoadLocation() on Windows program panic unless it finds zoneinfo.zip file in $GOROOT/lib/time/zoneinfo.zip. Even with ZONEINFO environment variable set you get the same panic.

Test program can be found here: http://play.golang.org/p/UgiIKSEiIP

Using golang 1.5.3 on Windows x86_64

Repro:

1. Take program from playground, and compile locally on windows. (Cross compiling will result in $GOROOT pointing to $GOROOT of the original Mac OS X machine)
2. Compile with go build and execute. Output should be something like this:

Found zoneinfo env: false, location: '' .
2009-11-11T07:00:00.0000+08:00

1. Copy zoneinfo.zip from $GOROOT\lib\time\ to another location. E.g. C:\zoneinfo.zip
2. Set ZONEINFO environment variable to point to previously copied zoneinfo E.g. set ZONEINFO=C:\zoneinfo.zip
3. Move or delete your $GOROOT directory, so that it cannot be found anymore.
4. Execute again

Expected output
Similar to output in step 2

Observed behavior
Program panics.

Found zoneinfo env: true, location: 'E:\zoneinfo.zip' .
open C:\Go\lib\time\zoneinfo.zip: The system cannot find the path specified.
panic: time: missing Location in call to Date

[bradfitz]

/cc @alexbrainman

[alexbrainman]

@geoko86 I tried to follow your instructions. But I cannot reproduce your problem.

C:\a>go version
go version go1.5.3 windows/386

C:\a>type main.go
package main

import (
        "fmt"
        "syscall"
        "time"
)

func main() {
        zi, found := syscall.Getenv("ZONEINFO")
        fmt.Printf("Found zoneinfo env: %v, location: '%v' .\n", found, zi)

        str := getTimeString("Asia/Hong_Kong", time.Now())
        fmt.Println(str)
}

func getTimeString(strLocation string, ts time.Time) string {
        const MyRFC3339 = "2006-01-02T15:04:05.0000Z07:00"

        var loc *time.Location
        println("--------------")
        loc, err := time.LoadLocation(strLocation)
        if err != nil {
                fmt.Println(err)
                return ""
        }

        return ts.In(loc).Format(MyRFC3339)
}

C:\a>copy %GOROOT%\lib\time\zoneinfo.zip c:\
        1 file(s) copied.

C:\a>set ZONEINFO=C:\zoneinfo.zip

C:\a>go run main.go
Found zoneinfo env: true, location: 'C:\zoneinfo.zip' .
--------------
2016-02-11T14:01:45.7686+08:00

C:\a>del %GOROOT%\lib\time\zoneinfo.zip

C:\a>go run main.go
Found zoneinfo env: true, location: 'C:\zoneinfo.zip' .
--------------
2016-02-11T14:02:02.7219+08:00

C:\a>

What did I do wrong?

Alex

[geoko86]

@alexbrainman Thanks for checking.
It figured out what went wrong. I double checked the zoneinfo.zip that i was using and it turned out, that the copy was incomplete, only 105kB vs some 352kB.

When I copied it again and pointed ZONEINFO to it, it works.

The error message was not completely clear to me, would have expected something along the line "found zoneinfo.zip, but I cannot read it".

It is safe to close this as user error. :)