src/Leevel/Validate/Validator.php
protected function hasFieldRuleWithoutParameter(string $field, string $rule)
    {
        $result = $this->hasFieldRuleWithoutParameterReal($field, $rule);

        if (!$result && $rule === static::DEFAULT_CONDITION) {
            return !$this->hasFieldRuleWithoutParameterReal($field, [
                static::CONDITION_MUST,
                static::CONDITION_VALUE,
            ]);
        }

        return $result;
    }
protected function hasFieldRuleWithoutParameter(string $field, string $rule)
    {
        $result = $this->hasFieldRuleWithoutParameterReal($field, $rule);

        if (!$result && $rule === static::DEFAULT_CONDITION) {
            return !$this->hasFieldRuleWithoutParameterReal($field, [
                static::CONDITION_MUST,
                static::CONDITION_VALUE,
            ]);
        }

        return $result;
    }
是否存在单个字段验证规则
不带条件的简单规则.

@param string $field
@param string $rule

@return mixed