def test_exposure_parser_mandatory(capsys):
"""Check that either the exposure time or the number of images is required."""
with pytest.raises(SystemExit, match="2"):
exposure_parser.parse_args([])
assert (
"error: one of the arguments -e/--exposure-time -n/--num-images is required"
in capsys.readouterr().err)
def test_exposure_time_no_help(capsys):
"""Check that this parser does not introduce a help flag."""
for flag in "-h", "--help":
with pytest.raises(SystemExit, match="2"):
exposure_parser.parse_args(["-e", ".1", flag])
assert f"error: unrecognized arguments: {flag}" in capsys.readouterr(
).err
def test_exposure_parser_invalid_image_number(capsys):
"""Check that mal-formed image number values are rejected with a help message."""
for number in "100.", "a", "100s", "0", "-1":
with pytest.raises(SystemExit, match="2"):
exposure_parser.parse_args(["-n", number])
msg = f"error: argument -n/--num-images: invalid positive_int value: '{number}'"
assert msg in capsys.readouterr().err
def test_exposure_parser_invalid_exposure_time(capsys):
"""Check that mal-formed exposure time values are rejected with a help message."""
for e in "foo", "1m", "0", "0s", "-1":
with pytest.raises(SystemExit, match="2"):
exposure_parser.parse_args(["-e", e])
assert (
f"error: argument -e/--exposure-time: invalid units_of_time value: '{e}'"
in capsys.readouterr().err)
def test_exposure_parser_exposure_time():
"""Test the behaviour of the exposure time/image number parser's exposure flag."""
for flag in "-e", "--exposure-time":
args = exposure_parser.parse_args([flag, ".1"])
assert args.exposure_time == pint.Quantity(100, "ms")
assert args.num_images is None
for exposure in ".1s", "ms", "100µs":
args = exposure_parser.parse_args(["-e", exposure])
assert args.exposure_time == pint.Quantity(exposure)
def test_exposure_time_mutually_exclusive(capsys):
"""Check that the exposure time and image number args are mutually exclusive."""
with pytest.raises(SystemExit, match="2"):
exposure_parser.parse_args(["-e", ".1", "-n", "100"])
assert (
"error: argument -n/--num-images: not allowed with argument -e/--exposure-time"
in capsys.readouterr().err)
with pytest.raises(SystemExit, match="2"):
exposure_parser.parse_args(["-n", "100", "-e", ".1"])
assert (
"error: argument -e/--exposure-time: not allowed with argument -n/--num-images"
in capsys.readouterr().err)
def test_exposure_parser_image_number():
"""Test the behaviour of the exposure time/image number parser's images flag."""
for flag in "-n", "--num-images":
args = exposure_parser.parse_args([flag, "100"])
assert args.exposure_time is None
assert args.num_images == 100