forms.py 文件源码

def clean(self):
        data = super(ProductClassForm, self).clean()
        has_variants = self.cleaned_data['has_variants']
        product_attr = set(self.cleaned_data['product_attributes'])
        variant_attr = set(self.cleaned_data['variant_attributes'])
        if not has_variants and len(variant_attr) > 0:
            msg = pgettext_lazy(
                'Product class form error',
                'Product variants are disabled.')
            self.add_error('variant_attributes', msg)
        if len(product_attr & variant_attr) > 0:
            msg = pgettext_lazy(
                'Product class form error',
                'A single attribute can\'t belong to both a product '
                'and its variant.')
            self.add_error('variant_attributes', msg)

        if self.instance.pk:
            variants_changed = not (self.fields['has_variants'].initial ==
                                    has_variants)
            if variants_changed:
                query = self.instance.products.all()
                query = query.annotate(variants_counter=Count('variants'))
                query = query.filter(variants_counter__gt=1)
                if query.exists():
                    msg = pgettext_lazy(
                        'Product class form error',
                        'Some products of this type have more than '
                        'one variant.')
                    self.add_error('has_variants', msg)
        return data