def test_rules():
g = lib.Bnf('s-indent(<n)')
assert g.expr == ("rule", "s-indent", "<n")
g = lib.Bnf('nb-json')
assert g.expr == ("rule", "nb-json")
g = lib.Bnf('s-separate(n,c)')
assert g.expr == ("rule", "s-separate", "n", "c")
def test_star():
g = lib.Bnf('"a"*')
assert g.expr == ("repeat", 0, math.inf, "a")
def test_opt():
g = lib.Bnf('"a"?')
assert g.expr == ("repeat", 0, 1, "a")
def test_or():
g = lib.Bnf('"0" | "9"')
assert g.expr == {'0', '9'}
def test_range():
g = lib.Bnf('[#x30-#x39]')
assert g.expr == range(0x30, 0x3A)
def test_unicode():
g = lib.Bnf('#x9')
assert g.expr == '\x09'
g = lib.Bnf('#x10FFFF')
assert g.expr == '\U0010ffff'
def test_empty():
g = lib.Bnf(' ')
assert g.expr == ('concat', )
def test_times_n():
g = lib.Bnf('"a" × n')
assert g.expr == ("repeat", "n", "n", "a")
def test_str():
g = lib.Bnf('"y" "a" "m" "l"')
assert g.expr == ('concat', 'y', 'a', 'm', 'l')
def test_char():
g = lib.Bnf('"c"')
assert g.expr == 'c'
def test_bad_string():
with pytest.raises(ValueError) as e_info:
lib.Bnf('"1\' "2"')
assert '"2"' in str(e_info.value)
assert 'expected' in str(e_info.value)
def test_remaining():
with pytest.raises(ValueError) as e_info:
lib.Bnf('"1" ^^garbage')
assert 'garbage' in str(e_info.value)
assert 'remaining' in str(e_info.value)
def test_comments():
g = lib.Bnf('[#x41-#x46] /* A-F */ | [#x61-#x66] /* a-f */ ')
assert g.expr == {range(0x41, 0x47), range(0x61, 0x67)}
def test_comment():
g = lib.Bnf(' /* Empty */ ')
assert g.expr == ('concat', )
def test_plus():
g = lib.Bnf('"a"+')
assert g.expr == ("repeat", 1, math.inf, "a")
def test_times():
g = lib.Bnf('"a" × 4')
def test_quote():
g = lib.Bnf(r'"\""')
assert g.expr == '"'
def test_backslash():
g = lib.Bnf(r'"\\"')
assert g.expr == '\\'
def test_switch():
g = lib.Bnf('t=a⇒"-" t=b⇒"+"')
assert g.expr == ("switch", "t", "a", "-", "b", "+")