def test_number():
int_pattern = r.seq(r.opt(r.alt(r.quote("+"), r.quote("-"))),
r.repeat(1, None, r.char_from("0123456789")))
num_pattern = r.seq(int_pattern,
r.opt(r.seq(r.quote("."),
r.opt(int_pattern))))
number = re.compile(num_pattern)
assert not number.fullmatch("foo")
assert not number.fullmatch("+")
assert number.fullmatch("0")
assert number.fullmatch("-42")
assert number.fullmatch("3.")
assert number.fullmatch("3.14")
def test_char_from():
pattern = r.char_from("x]")
assert re.fullmatch(pattern, "x")
assert re.fullmatch(pattern, "]")
assert not re.fullmatch(pattern, "foo")
def test_char_from_string_needing_escape():
assert r.char_from("^x-z]") == r"[]xz^-]"
def test_char_from_simple_string():
assert r.char_from("abcABC") == "[abcABC]"
def test_char_from_single_char():
assert r.char_from("X") == "(X)"
assert r.char_from(".") == r"(\.)"
def test_char_from_empty_string():
assert r.char_from("") == "()"