def test_when_input_is_closed_reading_any_output_gives_empty_string():
with nested(Pipe(), Pipe(), Pipe()) as (p1, p2, p3):
with tee(p1.read_fd, (p2.write_fd, p3.write_fd)).background():
p1.close_write()
assert os.read(p2.read_fd, 4096) == ''
assert os.read(p3.read_fd, 4096) == ''
assert p2.write_closed
assert p3.write_closed
def test_can_tee_to_stdout_and_a_simple_pipe():
with nested(Pipe(), Pipe()) as (p1, p2):
with tee(p1.read_fd, (sys.stdout.fileno(), p2.write_fd)).background():
# Write to input pipe, the output should show up on one output
# pipe and stdout (though there's no easy way to check this)
os.write(p1.write_fd, 'foobar')
os.close(p1.write_fd)
assert os.read(p2.read_fd, 6) == 'foobar'
def test_tee_can_capture_subprocess_output_and_send_to_stdout():
with nested(Pipe(), Pipe()) as (in_pipe, out_pipe):
with tee(in_pipe.read_fd, (sys.stdout.fileno(), out_pipe.write_fd)).background():
echo = subprocess.Popen(['echo', 'hello'], stdout=in_pipe.write_fd)
echo.wait()
os.close(in_pipe.write_fd)
captured_output = os.read(out_pipe.read_fd, 8192)
assert captured_output == 'hello\n'
def test_tee_can_handle_pipe_closures_gracefully():
with nested(Pipe(), Pipe(), Pipe()) as (p1, p2, p3):
with tee(p1.read_fd, (p2.write_fd, p3.write_fd)).background():
os.write(p1.write_fd, "Hello!\n")
p1.close_write()
assert p2.write_closed
assert p3.write_closed
assert os.read(p2.read_fd, 100) == "Hello!\n"
assert os.read(p3.read_fd, 100) == "Hello!\n"
def test_can_tee_to_two_pipes():
with nested(Pipe(), Pipe(), Pipe()) as (p1, p2, p3):
with tee(p1.read_fd, (p2.write_fd, p3.write_fd)).background():
# Write to input pipe, the output should show up on one output
# pipe and stdout (though there's no easy way to check this)
os.write(p1.write_fd, 'foobar')
os.close(p1.write_fd)
assert os.read(p2.read_fd, 6) == 'foobar'
assert os.read(p3.read_fd, 6) == 'foobar'
