horse: fix formatting TenThousandths in (-1, 0)

horse/skill.go

@@ -12,11 +12,12 @@ type TenThousandths int32
 
 func (x TenThousandths) String() string {
 	b := make([]byte, 0, 12)
+	if x < 0 {
+		x = -x
+		b = append(b, '-')
+	}
 	b = strconv.AppendInt(b, int64(x/1e4), 10)
 	if x%1e4 != 0 {
-		if x < 0 {
-			x = -x
-		}
 		b = append(b, '.')
 		b = fmt.Appendf(b, "%04d", x%1e4)
 		b = bytes.TrimRight(b, "0")

horse/skill_test.go

@@ -40,6 +40,8 @@ func TestTenThousandthsString(t *testing.T) {
 		want string
 	}{
 		{0, "0"},
+		{500, "0.05"},
+		{-500, "-0.05"},
 		{10000, "1"},
 		{-10000, "-1"},
 		{15000, "1.5"},