hspec-discover: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/hspec-discover - from package: libghc-hspec-dev

You may install the required package with command apt-get install {package}

Error in other languages:
hspec-discover: bevel nie gevind nie
hspec-discover: comandă negăsită
hspec-discover: comando não encontrado
hspec-discover: commande introuvable
hspec-discover: command not found
hspec-discover: käsku ei ole
hspec-discover: không tìm thấy lệnh
hspec-discover: komanda nerasta
hspec-discover: Kommando nicht gefunden.
hspec-discover: kommandot finns inte
hspec-discover: komut yok
hspec-discover: nie znaleziono polecenia
hspec-discover: níor aimsíodh an t-ordú
hspec-discover: no se encontró la orden
hspec-discover: no s'ha trobat l'ordre
hspec-discover: opdracht niet gevonden
hspec-discover: parancs nem található
hspec-discover: perintah tidak ditemukan
hspec-discover: príkaz nenájdený
hspec-discover: příkaz nenalezen
hspec-discover: команда не найдена
hspec-discover: командата не е открита
hspec-discover: 命令找不到
hspec-discover: コマンドが見つかりません