"""Check that the shell processes a pipe before its writer closes it."""
import select
import subprocess
import sys
from pathlib import Path

TIMEOUT = 4
shell = str(Path(sys.argv[1] if len(sys.argv) > 1 else "rc2").resolve())
process = subprocess.Popen([shell, "-I"], stdin=subprocess.PIPE,
                           stdout=subprocess.PIPE, stderr=subprocess.PIPE)
try:
    process.stdin.write(b"echo first\n")
    process.stdin.flush()
    ready, _, _ = select.select([process.stdout], [], [], TIMEOUT)
    assert ready, "The shell waited for EOF before it processed a complete command"
    assert process.stdout.readline() == b"first\n"
    process.stdin.write(b"fn f {\necho second\n}\nf")
    process.stdin.close()
    assert process.wait(timeout=TIMEOUT) == 0
    assert process.stdout.read() == b"second\n"
    assert process.stderr.read() == b""
    print("Stream tests passed")
finally:
    if process.poll() is None:
        process.kill()
        process.wait()

result = subprocess.run([shell, "-I"], input=b"echo 'a\x00b'\n", capture_output=True, timeout=TIMEOUT)
assert result.returncode == 1 and not result.stdout and result.stderr, "The shell accepted a NUL source byte"