Struggling to rewrite SalesRule Model

Question

I am trying to rewrite Mage_SalesRule_Model_Rule_Condition_Product_Subselect but it seems like my changes are not being picked. Below is what i've done trying to rewrite the Model.

app/code/local/Invent/SalesRule/etc/config.xml

<?xml version="1.0"?>
<config>
    <modules>
        <Invent_SalesRule>
            <version>0.0.1</version>
        </Invent_SalesRule>
    </modules>
    <global>
        <models>
            <salesrule>
                <rewrite>
                    <rule_condition_product_subselect>Invent_SalesRule_Model_Rule_Condition_Product_Subselect</rule_condition_product_subselect>
                </rewrite>
            </salesrule>
        </models>
    </global>
</config>

app/etc/modules/Invent_SalesRule.xml

<config>
    <modules>
        <Invent_SalesRule>
            <active>true</active>
            <codePool>local</codePool>
        </Invent_SalesRule>
    </modules>
</config>

app/code/local/Invent/SalesRule/Model/Rule/Condition/Product/Subselect.php

<?php
class Invent_SalesRule_Model_Rule_Condition_Product_Subselect extends Mage_SalesRule_Model_Rule_Condition_Product_Subselect
{
    public function validate(Varien_Object $object)
    {
       // the code
    }
}

Answer 1

Please use below code in respective folders

app\etc\modules\Invent_SalesRule.xml

<?xml version="1.0"?>
<config>
  <modules>
    <Invent_SalesRule>
      <active>true</active>
      <codePool>local</codePool>
      <version>0.1.0</version>
    </Invent_SalesRule>
  </modules>
</config>

app\code\local\Invent\SalesRule\etc\config.xml

<?xml version="1.0"?>
<config>
  <modules>
    <Invent_SalesRule>
      <version>0.1.0</version>
    </Invent_SalesRule>
  </modules>
  <global>   
    <models>
            <salesrule>
                <rewrite>
                    <rule_condition_product_subselect>Invent_SalesRule_Model_SalesRule_Rule_Condition_Product_Subselect</rule_condition_product_subselect>
                </rewrite>
            </salesrule>
    </models>
  </global>
</config> 

app\code\local\Invent\SalesRule\Model\SalesRule\Rule\Condition\Product\Subselect.php

class Invent_SalesRule_Model_SalesRule_Rule_Condition_Product_Subselect extends Mage_SalesRule_Model_Rule_Condition_Product_Subselect
{
}

Hope it will help you!.