$ juju set juju-reports lp-key=""
panic: runtime error: index out of range
goroutine 1 [running]:
runtime.panic(0xcc1300, 0x19ec9b7)
/usr/lib/go/src/pkg/runtime/panic.c:266 +0xb6
main.(*SetCommand).Run(0xc21010af80, 0xc2100e2000, 0x0, 0x0)
/build/buildd/juju-core-1.20.1/src/github.com/juju/juju/cmd/juju/set.go:92 +0x62d
github.com/juju/juju/cmd/envcmd.(*environCommandWrapper).Run(0xc21010cb00, 0xc2100e2000, 0xb27740, 0xc21014b3f0)
/build/buildd/juju-core-1.20.1/src/github.com/juju/juju/cmd/envcmd/environmentcommand.go:1 +0x3d
main.(*envCmdWrapper).Run(0xc21010cb20, 0xc2100e2000, 0x0, 0x0)
/build/buildd/juju-core-1.20.1/src/github.com/juju/juju/cmd/juju/addmachine.go:1 +0x3d
github.com/juju/cmd.(*SuperCommand).Run(0xc2100ee160, 0xc2100e2000, 0xc2100e2000, 0x0)
/build/buildd/juju-core-1.20.1/src/github.com/juju/cmd/supercommand.go:321 +0x3ca
github.com/juju/cmd.Main(0x7fe47f763188, 0xc2100ee160, 0xc2100e2000, 0xc21000a010, 0x3, ...)
/build/buildd/juju-core-1.20.1/src/github.com/juju/cmd/cmd.go:247 +0x283
main.Main(0xc21000a000, 0x4, 0x4)
/build/buildd/juju-core-1.20.1/src/github.com/juju/juju/cmd/juju/main.go:77 +0xada
main.main()
/build/buildd/juju-core-1.20.1/src/github.com/juju/juju/cmd/juju/main.go:174 +0x44
goroutine 3 [syscall]:
os/signal.loop()
/usr/lib/go/src/pkg/os/signal/signal_unix.go:21 +0x1e
created by os/signal.init·1
/usr/lib/go/src/pkg/os/signal/signal_unix.go:27 +0x31
goroutine 12 [syscall]:
runtime.goexit()
/usr/lib/go/src/pkg/runtime/proc.c:1394
$ juju --version
1.20.1-trusty-amd64
