specify posix.stdlib:
- before:
    stdlib = require "posix.stdlib"


- describe abort:
  - context with bad arguments:
      badargs.diagnose (stdlib.abort, "()")


- describe getenv:
  - before:
      getenv = stdlib.getenv

  - context with bad arguments:
      badargs.diagnose (getenv, "(?string)")

  - it fetches a table of process environment variables: |
      volatile = { _=true, CWD=true, LUA_PATH=true, PWD=true, SHLVL=true, }
      for k,v in pairs (getenv ()) do
       if not volatile[k] then
         expect (hell.spawn ('echo "' .. k .. '=$' .. k .. '"')).
           to_contain_output (k.."="..v)
       end
      end
  - it fetches a named process environment variable:
      expect (getenv "USER").to_be (cmd_output ('echo "$USER"'))
      expect (getenv "HOME").to_be (cmd_output ('echo "$HOME"'))
      expect (getenv "SHELL").to_be (cmd_output ('echo "$SHELL"'))
  - it returns nil for an absent environment setting:
      expect (getenv "very_unlikely_to_be_set").to_be (nil)


- describe grantpt:
  - context with bad arguments:
      badargs.diagnose (stdlib.grantpt, "(int)")


- describe mkdtemp:
  - before:
      st = require "posix.sys.stat"
      mkdtemp = stdlib.mkdtemp
      stat, IFMT, IFDIR, IRWXU = st.stat, st.S_IFMT, st.S_IFDIR, st.S_IRWXU
      IRWXA = bor (st.S_IRWXU, st.S_IRWXG, st.S_IRWXO)

  - context with bad arguments:
      badargs.diagnose (mkdtemp, "(string)")

  - it creates a temporary directory from a template:
      dir, errmsg = mkdtemp (template)
      expect (dir).not_to_be (nil)
      dirstat = stat (dir)
      expect (band (dirstat.st_mode, IFMT)).to_be (IFDIR)
      expect (band (dirstat.st_mode, IRWXA)).to_be (IRWXU)
      rmtmp (dir)


- describe mkstemp:
  - before:
      fc = require "posix.fcntl"
      st = require "posix.sys.stat"
      unistd = require "posix.unistd"
      O_RDONLY, open = fc.O_RDONLY, fc.open
      mkstemp = stdlib.mkstemp
      close, isatty, read, write =
        unistd.close, unistd.isatty, unistd.read, unistd.write
      stat, IFMT, IFREG = st.stat, st.S_IFMT, st.S_IFREG
      IRW_U = bor (st.S_IRUSR, st.S_IWUSR)
      IRWXA = bor (st.S_IRWXU, st.S_IRWXG, st.S_IRWXO)
      fd, path = mkstemp (template)
  - after:
      close (fd)
      os.remove (path)

  - context with bad arguments:
      badargs.diagnose (mkstemp, "(string)")

  - it creates a temporary file from a template:
      expect (fd).not_to_be (nil)
      write (fd, "12345")
      expect (isatty (fd)).not_to_be (true)
      fstat = stat (path)
      expect (band (fstat.st_mode, IFMT)).to_be (IFREG)
      expect (band (fstat.st_mode, IRWXA)).to_be (IRW_U)
      expect (fstat.st_size).to_be (5)
      fd2 = open (path, O_RDONLY)
      expect (read (fd2, 5)).to_be "12345"
      close (fd2)
  - it creates a new temporary file on each call:
      fd2, another = mkstemp (template)
      expect (fd2).not_to_be (fd)
      expect (another).not_to_be (path)
      close (fd2)
      os.remove (another)


- describe openpt:
  - before:
      fc = require "posix.fcntl"
      st = require "posix.sys.stat"
      close = require "posix.unistd".close
      grantpt, openpt, ptsname, unlockpt =
        stdlib.grantpt, stdlib.openpt, stdlib.ptsname, stdlib.unlockpt
      O_RDWR, O_NOCTTY, open = fc.O_RDWR, fc.O_NOCTTY, fc.open
      stat, IFMT, IFCHR = st.stat, st.S_IFMT, st.S_IFCHR

  - context with bad arguments:
      badargs.diagnose (openpt, "(int)")

  - it can create a pseudoterminal:
      masterfd = openpt (bor (O_RDWR, O_NOCTTY))
      expect (type (masterfd)).to_be "number"
      expect (masterfd > 0).to_be (true)
      expect (Emsg (grantpt (masterfd))).to_be ""
      expect (Emsg (unlockpt (masterfd))).to_be ""
      slavename = ptsname (masterfd)
      slavestat = stat (slavename)
      expect (band (slavestat.st_mode, IFMT)).to_be (IFCHR)
      slavefd = open (slavename, bor (O_RDWR, O_NOCTTY))
      expect (type (slavefd)).to_be "number"
      expect (slavefd > 0).to_be (true)
      close (slavefd)
      close (masterfd)


- describe ptsname:
  - context with bad arguments:
      badargs.diagnose (stdlib.ptsname, "(int)")


- describe realpath:
  - context with bad arguments:
      badargs.diagnose (stdlib.realpath, "(string)")


- describe setenv:
  - before:
      getenv, setenv = stdlib.getenv, stdlib.setenv

  - context with bad arguments:
      badargs.diagnose (stdlib.setenv, "(string, ?string, ?any)")

  - it sets a new value in the process environment:
      setenv ("MYVAR", "123")
      expect (getenv "MYVAR").to_be "123"
      setenv ("MYVAR", nil)
      expect (getenv "MYVAR").to_be (nil)


- describe unlockpt:
  - context with bad arguments:
      badargs.diagnose (stdlib.unlockpt, "(int)")