Return None for empty nested selectors

itemloaders/__init__.py

@@ -154,7 +154,7 @@ def item(self) -> Any:
         else:
             return self._local_item
 
-    def nested_xpath(self, xpath: str, **context: Any) -> Self:
+    def nested_xpath(self, xpath: str, **context: Any) -> Optional[Self]:
         """
         Create a nested loader with an xpath selector.
         The supplied selector is applied relative to selector associated
@@ -165,11 +165,13 @@ def nested_xpath(self, xpath: str, **context: Any) -> Self:
         self._check_selector_method()
         assert self.selector
         selector = self.selector.xpath(xpath)
+        if not selector:
+            return None
         context.update(selector=selector)
         subloader = self.__class__(item=self.item, parent=self, **context)
         return subloader
 
-    def nested_css(self, css: str, **context: Any) -> Self:
+    def nested_css(self, css: str, **context: Any) -> Optional[Self]:
         """
         Create a nested loader with a css selector.
         The supplied selector is applied relative to selector associated
@@ -180,6 +182,8 @@ def nested_css(self, css: str, **context: Any) -> Self:
         self._check_selector_method()
         assert self.selector
         selector = self.selector.css(css)
+        if not selector:
+            return None
         context.update(selector=selector)
         subloader = self.__class__(item=self.item, parent=self, **context)
         return subloader

tests/test_nested_loader.py

@@ -117,3 +117,8 @@ def test_nested_load_item(self):
         self.assertEqual(item["name"], ["marta"])
         self.assertEqual(item["url"], ["http://www.scrapy.org"])
         self.assertEqual(item["image"], ["/images/logo.png"])
+
+    def test_nested_empty_selector(self):
+        loader = ItemLoader(selector=self.selector)
+        assert loader.nested_xpath("//bar") is None
+        assert loader.nested_css(".foo") is None