Fixed boolean validation to handle bool kind (#988)

baked_in.go

@@ -1484,11 +1484,16 @@ func isAlphaUnicode(fl FieldLevel) bool {
 	return alphaUnicodeRegex.MatchString(fl.Field().String())
 }
 
-// isBoolean is the validation function for validating if the current field's value can be safely converted to a boolean.
+// isBoolean is the validation function for validating if the current field's value is a valid boolean value or can be safely converted to a boolean value.
 func isBoolean(fl FieldLevel) bool {
+	switch fl.Field().Kind() {
+	case reflect.Bool:
+		return true
+	default:
 		_, err := strconv.ParseBool(fl.Field().String())
 		return err == nil
 	}
+}
 
 // isDefault is the opposite of required aka hasValue
 func isDefault(fl FieldLevel) bool {

validator_test.go

@@ -8302,6 +8302,43 @@ func TestNumeric(t *testing.T) {
 	errs = validate.Var(i, "numeric")
 	Equal(t, errs, nil)
 }
+func TestBoolean(t *testing.T) {
+	validate := New()
+
+	b := true
+	errs := validate.Var(b, "boolean")
+	Equal(t, errs, nil)
+
+	b = false
+	errs = validate.Var(b, "boolean")
+	Equal(t, errs, nil)
+
+	s := "true"
+	errs = validate.Var(s, "boolean")
+	Equal(t, errs, nil)
+
+	s = "false"
+	errs = validate.Var(s, "boolean")
+	Equal(t, errs, nil)
+
+	s = "0"
+	errs = validate.Var(s, "boolean")
+	Equal(t, errs, nil)
+
+	s = "1"
+	errs = validate.Var(s, "boolean")
+	Equal(t, errs, nil)
+
+	s = "xyz"
+	errs = validate.Var(s, "boolean")
+	NotEqual(t, errs, nil)
+	AssertError(t, errs, "", "", "", "", "boolean")
+
+	s = "1."
+	errs = validate.Var(s, "boolean")
+	NotEqual(t, errs, nil)
+	AssertError(t, errs, "", "", "", "", "boolean")
+}
 
 func TestAlphaNumeric(t *testing.T) {
 	validate := New()