LibHTML: Support the :first-child and :last-child pseudo classes

3 files changed, 14 insertions, 0 deletions

diff --git a/Libraries/LibHTML/CSS/Selector.h b/Libraries/LibHTML/CSS/Selector.h
index 288f16a9a5..e0e68e2be6 100644
--- a/Libraries/LibHTML/CSS/Selector.h
+++ b/Libraries/LibHTML/CSS/Selector.h
@@ -20,6 +20,8 @@ public:
             None,
             Link,
             Hover,
+            FirstChild,
+            LastChild,
         };
         PseudoClass pseudo_class { PseudoClass::None };
 
diff --git a/Libraries/LibHTML/CSS/SelectorEngine.cpp b/Libraries/LibHTML/CSS/SelectorEngine.cpp
index f33018607d..affedd2128 100644
--- a/Libraries/LibHTML/CSS/SelectorEngine.cpp
+++ b/Libraries/LibHTML/CSS/SelectorEngine.cpp
@@ -27,6 +27,14 @@ bool matches(const Selector::SimpleSelector& component, const Element& element)
         if (!matches_hover_pseudo_class(element))
             return false;
         break;
+    case Selector::SimpleSelector::PseudoClass::FirstChild:
+        if (element.previous_element_sibling())
+            return false;
+        break;
+    case Selector::SimpleSelector::PseudoClass::LastChild:
+        if (element.next_element_sibling())
+            return false;
+        break;
     }
 
     switch (component.attribute_match_type) {
diff --git a/Libraries/LibHTML/Parser/CSSParser.cpp b/Libraries/LibHTML/Parser/CSSParser.cpp
index 786c713591..6cfc93c75a 100644
--- a/Libraries/LibHTML/Parser/CSSParser.cpp
+++ b/Libraries/LibHTML/Parser/CSSParser.cpp
@@ -321,6 +321,10 @@ public:
                 simple_selector.pseudo_class = Selector::SimpleSelector::PseudoClass::Link;
             else if (pseudo_name == "hover")
                 simple_selector.pseudo_class = Selector::SimpleSelector::PseudoClass::Hover;
+            else if (pseudo_name == "first-child")
+                simple_selector.pseudo_class = Selector::SimpleSelector::PseudoClass::FirstChild;
+            else if (pseudo_name == "last-child")
+                simple_selector.pseudo_class = Selector::SimpleSelector::PseudoClass::LastChild;
         }
 
         return simple_selector;