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_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_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_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'
def test_pipe_closes_fds_on_garbage_collection():
pipe = Pipe()
ident = id(pipe)
read_fd, write_fd = pipe.read_fd, pipe.write_fd
# Check that the pipe gets collected.
assert object_exists(ident)
del pipe
gc.collect()
assert not object_exists(ident)
ensure_fd_closed(read_fd)
ensure_fd_closed(write_fd)
def test_multiple_closes_are_a_noop():
pipe = Pipe()
pipe.close()
pipe.close()
ensure_pipe_closed(pipe)
def test_close_closes_both_fds():
pipe = Pipe()
pipe.close()
ensure_pipe_closed(pipe)
def test_closed_indicates_whether_an_fd_is_closed():
pipe = Pipe()
os.close(pipe.read_fd)
assert pipe.read_closed
os.close(pipe.write_fd)
assert pipe.write_closed
def test_pipe_as_context_manager_closes_its_file_descriptors():
with Pipe() as pipe:
pass
ensure_pipe_closed(pipe)
def test_non_blocking_pipes_raise_EAGAIN_when_no_data_are_ready_to_read():
pipe = Pipe(non_blocking=True)
with assert_raises(IOError) as cm:
pipe.read_file.read()
assert cm.exception.errno == errno.EAGAIN
def test_smoke_test_pipe():
pipe = Pipe()
pipe.write_file.write('FooBar\n')
pipe.write_file.flush()
assert pipe.read_file.readline() == 'FooBar\n'
def test_pipe_gets_read_and_write_file_handles():
pipe = Pipe()
assert hasattr(pipe.read_file, 'read')
assert hasattr(pipe.write_file, 'write')
def test_pipe_gets_read_and_write_file_descriptors():
pipe = Pipe()
assert isinstance(pipe.read_fd, int)
assert isinstance(pipe.write_fd, int)