! garble
stderr -count=1 'Usage'
stderr 'garble \[flags\] build'
! stderr 'usage: go build'
! stdout .

! garble -h
stderr 'garble \[flags\] build'
! stdout .

! garble help
stderr 'garble \[flags\] build'
! stdout .

! garble build -h
stderr 'garble \[flags\] build'
! stderr 'usage: go build'
! stdout .

! garble -badflag
stderr 'garble \[flags\] build'
! stdout .

! garble badcmd
stderr 'unknown command'

[!windows] ! garble /does/not/exist/compile
[!windows] stderr 'no such file'
[windows] ! garble C:\does\not\exist\compile
[windows] stderr 'file does not exist'