exec git init
exec git config user.email i@example.com
exec git config user.name someone
exec git checkout -b main

exec git add file
exec sed -i '1d' file

exec git status --porcelain --branch
stdout '## No commits yet on .+\nAM file'

env WANT_STATUS='NumModified=1 NumStaged=1 IsInitial=true LocalBranch=main State=Default'
gitstatus
! stderr .

-- file --
line1
line2