# We use a simple Go program to report many Go versions.
# The program also errors on any command other than "go version",
# which saves us having to rebuild main.go many times.
go build -o .bin/go$exe ./fakego
env PATH=${WORK}/.bin${:}${PATH}

# An empty go version.
env GO_VERSION=''
! garble build
stderr 'Can''t get Go version'

# An invalid devel string.
env GO_VERSION='go version devel someinvalidversion'
! garble build
stderr 'Can''t recognize devel build timestamp'

# An invalid devel date.
env GO_VERSION='go version devel +afb5fca Sun Sep 99 99:99:99 9999 +0000 linux/amd64'
! garble build
stderr 'Can''t recognize devel build timestamp: parsing time'

# We should error on a devel version that's too old.
env GO_VERSION='go version devel +afb5fca Sun Aug 07 00:00:00 2020 +0000 linux/amd64'
! garble build
stderr 'Go version.*Aug 07.*too old; please upgrade to Go 1.16.x or a newer devel version'

# A future devel timestamp should be fine.
env GO_VERSION='go version devel +afb5fca Sun Sep 13 07:54:42 2021 +0000 linux/amd64'
! garble build
stderr 'mocking the real build'

# We should error on a stable version that's too old.
env GO_VERSION='go version go1.14 windows/amd64'
! garble build
stderr 'Go version.*go1.14.*too old; please upgrade to Go 1.16.x'
! stderr 'or a newer devel version'

# We should accept a future stable version.
env GO_VERSION='go version go1.16.2 windows/amd64'
! garble build
stderr 'mocking the real build'

-- go.mod --
module test/main

go 1.16
-- main.go --
package main

func main() {}

-- fakego/main.go --
package main

import (
	"fmt"
	"os"
)

func main() {
	if len(os.Args) > 0 && os.Args[1] == "version" {
		fmt.Println(os.Getenv("GO_VERSION"))
		return
	}
	fmt.Fprintln(os.Stderr, "mocking the real build")
	os.Exit(1)
}