在使用 Odoo 的时候，发现 Odoo 的一个 bug，这里贴出来。

先来看一段odoo的代码（addons/product/models/product.py）:

@api.multi
def unlink(self):
    unlink_products = self.env['product.product']
    unlink_templates = self.env['product.template']
    for product in self:
        # Check if product still exists, in case it has been unlinked by unlinking its template
        if not product.exists():
            continue
        # Check if the product is last product of this template...
        other_products = self.search([('product_tmpl_id', '=', product.product_tmpl_id.id), ('id', '!=', product.id)])
        # ... and do not delete product template if it's configured to be created "on demand"
        if not other_products and not product.product_tmpl_id.has_dynamic_attributes():
            unlink_templates |= product.product_tmpl_id
        unlink_products |= product
    res = super(ProductProduct, unlink_products).unlink()
    # delete templates after calling super, as deleting template could lead to deleting
    # products due to ondelete='cascade'
    unlink_templates.unlink()
    return res

这段代码的作用是在删除商品的时候，去检查商品模板，如果商品模板没有关联的其它商品，那么就把商品模板一起删掉，正常情况下，这是没有问题的。

但是，这里有考虑不周到的地方，如果一个产品有多个变体，当其中的一个变体已经归档的话，other_products = self.search([('product_tmpl_id', '=', product.product_tmpl_id.id), ('id', '!=', product.id)]) 这条语句是查不出来已经归档的变体的，从而导致在删除 templates 造成数据库约束错误。

正确的做法如下所示：

@api.multi
def unlink(self):
    unlink_products = self.env['product.product']
    unlink_templates = self.env['product.template']
    for product in self:
        # Check if product still exists, in case it has been unlinked by unlinking its template
        if not product.exists():
            continue
        # Check if the product is last product of this template...
        other_products = self.search([('product_tmpl_id', '=', product.product_tmpl_id.id), ('id', '!=', product.id), \
                                '|', ('active', '=', False), ('active', '=', True)])
        # ... and do not delete product template if it's configured to be created "on demand"
        if not other_products and not product.product_tmpl_id.has_dynamic_attributes():
            unlink_templates |= product.product_tmpl_id
        unlink_products |= product
    res = super(ProductProduct, unlink_products).unlink()
    # delete templates after calling super, as deleting template could lead to deleting
    # products due to ondelete='cascade'
    unlink_templates.unlink()
    return res

遵循最小改动原则，只需要把查询搞成 other_products = self.search([('product_tmpl_id', '=', product.product_tmpl_id.id), ('id', '!=', product.id), '|', ('active', '=', False), ('active', '=', True)]) 即可。

向 Odoo 官方提交了一个 : PR

后来，还有一种更好的做法：

other_products = self.env['product.product'].with_context(active_test=False).\
                                    search([('product_tmpl_id', '=', product.product_tmpl_id.id), ('id', 'not in', self.ids)])

这种写法看起来更好。

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时间线

发布日期：2018-12-25

最后修改日期：2019-03-14