feat(ansi): add WcStringWidth function test

ansi/width_test.go

@@ -9,29 +9,31 @@ var cases = []struct {
 	input    string
 	stripped string
 	width    int
+	wcwidth  int
 }{
-	{"empty", "", "", 0},
-	{"ascii", "hello", "hello", 5},
-	{"emoji", "👋", "👋", 2},
-	{"wideemoji", "🫧", "🫧", 2},
-	{"combining", "a\u0300", "à", 1},
-	{"control", "\x1b[31mhello\x1b[0m", "hello", 5},
-	{"csi8", "\x9b38;5;1mhello\x9bm", "hello", 5},
-	{"osc", "\x9d2;charmbracelet: ~/Source/bubbletea\x9c", "", 0},
-	{"controlemoji", "\x1b[31m👋\x1b[0m", "👋", 2},
-	{"oscwideemoji", "\x1b]2;title👨‍👩‍👦\x07", "", 0},
-	{"oscwideemoji", "\x1b[31m👨‍👩‍👦\x1b[m", "👨\u200d👩\u200d👦", 2},
-	{"multiemojicsi", "👨‍👩‍👦\x9b38;5;1mhello\x9bm", "👨‍👩‍👦hello", 7},
-	{"osc8eastasianlink", "\x9d8;id=1;https://example.com/\x9c打豆豆\x9d8;id=1;\x07", "打豆豆", 6},
-	{"dcsarabic", "\x1bP?123$pسلام\x1b\\اهلا", "اهلا", 4},
-	{"newline", "hello\nworld", "hello\nworld", 10},
-	{"tab", "hello\tworld", "hello\tworld", 10},
-	{"controlnewline", "\x1b[31mhello\x1b[0m\nworld", "hello\nworld", 10},
-	{"style", "\x1B[38;2;249;38;114mfoo", "foo", 3},
-	{"unicode", "\x1b[35m“box”\x1b[0m", "“box”", 5},
-	{"just_unicode", "Claire’s Boutique", "Claire’s Boutique", 17},
-	{"unclosed_ansi", "Hey, \x1b[7m\n猴", "Hey, \n猴", 7},
-	{"double_asian_runes", " 你\x1b[8m好.", " 你好.", 6},
+	{"empty", "", "", 0, 0},
+	{"ascii", "hello", "hello", 5, 5},
+	{"emoji", "👋", "👋", 2, 2},
+	{"wideemoji", "🫧", "🫧", 2, 2},
+	{"combining", "a\u0300", "à", 1, 1},
+	{"control", "\x1b[31mhello\x1b[0m", "hello", 5, 5},
+	{"csi8", "\x9b38;5;1mhello\x9bm", "hello", 5, 5},
+	{"osc", "\x9d2;charmbracelet: ~/Source/bubbletea\x9c", "", 0, 0},
+	{"controlemoji", "\x1b[31m👋\x1b[0m", "👋", 2, 2},
+	{"oscwideemoji", "\x1b]2;title👨‍👩‍👦\x07", "", 0, 0},
+	{"oscwideemoji", "\x1b[31m👨‍👩‍👦\x1b[m", "👨\u200d👩\u200d👦", 2, 2},
+	{"multiemojicsi", "👨‍👩‍👦\x9b38;5;1mhello\x9bm", "👨‍👩‍👦hello", 7, 7},
+	{"osc8eastasianlink", "\x9d8;id=1;https://example.com/\x9c打豆豆\x9d8;id=1;\x07", "打豆豆", 6, 6},
+	{"dcsarabic", "\x1bP?123$pسلام\x1b\\اهلا", "اهلا", 4, 4},
+	{"newline", "hello\nworld", "hello\nworld", 10, 10},
+	{"tab", "hello\tworld", "hello\tworld", 10, 10},
+	{"controlnewline", "\x1b[31mhello\x1b[0m\nworld", "hello\nworld", 10, 10},
+	{"style", "\x1B[38;2;249;38;114mfoo", "foo", 3, 3},
+	{"unicode", "\x1b[35m“box”\x1b[0m", "“box”", 5, 5},
+	{"just_unicode", "Claire’s Boutique", "Claire’s Boutique", 17, 17},
+	{"unclosed_ansi", "Hey, \x1b[7m\n猴", "Hey, \n猴", 7, 7},
+	{"double_asian_runes", " 你\x1b[8m好.", " 你好.", 6, 6},
+	{"flag", "🇸🇦", "🇸🇦", 2, 1},
 }
 
 func TestStrip(t *testing.T) {
@@ -54,6 +56,16 @@ func TestStringWidth(t *testing.T) {
 	}
 }
 
+func TestWcStringWidth(t *testing.T) {
+	for i, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+			if width := WcStringWidth(c.input); width != c.wcwidth {
+				t.Errorf("test case %d failed: expected %d, got %d", i+1, c.wcwidth, width)
+			}
+		})
+	}
+}
+
 func BenchmarkStringWidth(b *testing.B) {
 	b.RunParallel(func(pb *testing.PB) {
 		b.ReportAllocs()