romannum_test.gno

 1package romannum
 2
 3import (
 4	"testing"
 5
 6	"gno.land/p/nt/uassert/v0"
 7)
 8
 9func TestToRoman(t *testing.T) {
10	cases := []struct {
11		in   int
12		want string
13	}{
14		{1, "I"},
15		{4, "IV"},
16		{9, "IX"},
17		{40, "XL"},
18		{90, "XC"},
19		{400, "CD"},
20		{900, "CM"},
21		{1994, "MCMXCIV"},
22		{2024, "MMXXIV"},
23		{3999, "MMMCMXCIX"},
24	}
25	for _, c := range cases {
26		uassert.Equal(t, c.want, ToRoman(c.in))
27	}
28}
29
30func TestParseRoman(t *testing.T) {
31	// canonical numerals round-trip back to their value
32	good := []struct {
33		in   string
34		want int
35	}{
36		{"I", 1},
37		{"IV", 4},
38		{"mmxxiv", 2024}, // case-insensitive
39		{" XLII ", 42},   // trimmed
40		{"MMMCMXCIX", 3999},
41	}
42	for _, c := range good {
43		got, ok := parseRoman(c.in)
44		uassert.True(t, ok)
45		uassert.Equal(t, c.want, got)
46	}
47
48	// malformed / non-canonical forms are rejected
49	bad := []string{"", "IIII", "VV", "IC", "MMMM", "XIↃ", "ABC"}
50	for _, s := range bad {
51		_, ok := parseRoman(s)
52		uassert.False(t, ok)
53	}
54}
55
56func TestRoundTrip(t *testing.T) {
57	for n := 1; n <= 3999; n++ {
58		got, ok := parseRoman(ToRoman(n))
59		uassert.True(t, ok)
60		uassert.Equal(t, n, got)
61	}
62}