LibWeb: Parse line names in grid track position properties

Parse line names when passed to the grid-column/row-start/end CSS
properties.

Userland/Libraries/LibWeb/CSS/GridTrackPlacement.cpp

@@ -15,6 +15,19 @@ GridTrackPlacement::GridTrackPlacement(int span_count_or_position, bool has_span
 {
 }
 
+GridTrackPlacement::GridTrackPlacement(String line_name, int span_count_or_position, bool has_span)
+    : m_type(has_span ? Type::Span : Type::Position)
+    , m_span_count_or_position(span_count_or_position)
+    , m_line_name(line_name)
+{
+}
+
+GridTrackPlacement::GridTrackPlacement(String line_name, bool has_span)
+    : m_type(has_span ? Type::Span : Type::Position)
+    , m_line_name(line_name)
+{
+}
+
 GridTrackPlacement::GridTrackPlacement()
     : m_type(Type::Auto)
 {
@@ -35,6 +48,9 @@ String GridTrackPlacement::to_string() const
         builder.append(String::number(m_span_count_or_position));
         builder.append(" "sv);
     }
+    if (has_line_name()) {
+        builder.append(m_line_name);
+    }
     return builder.to_string();
 }
 

Userland/Libraries/LibWeb/CSS/GridTrackPlacement.h

@@ -18,7 +18,9 @@ public:
         Auto
     };
 
+    GridTrackPlacement(String line_name, int span_count_or_position, bool has_span = false);
     GridTrackPlacement(int span_count_or_position, bool has_span = false);
+    GridTrackPlacement(String line_name, bool has_span = false);
     GridTrackPlacement();
 
     static GridTrackPlacement make_auto() { return GridTrackPlacement(); };
@@ -26,10 +28,13 @@ public:
     bool is_span() const { return m_type == Type::Span; }
     bool is_position() const { return m_type == Type::Position; }
     bool is_auto() const { return m_type == Type::Auto; }
-    bool is_auto_positioned() const { return m_type == Type::Auto || m_type == Type::Span; }
+    bool is_auto_positioned() const { return m_type == Type::Auto || (m_type == Type::Span && !has_line_name()); }
+
+    bool has_line_name() const { return !m_line_name.is_empty(); }
 
     int raw_value() const { return m_span_count_or_position; }
     Type type() const { return m_type; }
+    String line_name() const { return m_line_name; }
 
     String to_string() const;
     bool operator==(GridTrackPlacement const& other) const
@@ -40,6 +45,7 @@ public:
 private:
     Type m_type;
     int m_span_count_or_position { 0 };
+    String m_line_name;
 };
 
 }

Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp

@@ -5655,6 +5655,13 @@ RefPtr<StyleValue> Parser::parse_grid_track_placement(Vector<ComponentValue> con
             return true;
         return false;
     };
+    auto is_line_name = [](Token token) -> bool {
+        // The <custom-ident> additionally excludes the keywords span and auto.
+        if (token.is(Token::Type::Ident) && !token.ident().equals_ignoring_case("span"sv) && !token.ident().equals_ignoring_case("auto"sv))
+            return true;
+        return false;
+    };
+
     auto tokens = TokenStream { component_values };
     tokens.skip_whitespace();
     auto current_token = tokens.next_token().token();
@@ -5666,11 +5673,14 @@ RefPtr<StyleValue> Parser::parse_grid_track_placement(Vector<ComponentValue> con
             return GridTrackPlacementStyleValue::create(CSS::GridTrackPlacement(1, true));
         if (is_valid_integer(current_token))
             return GridTrackPlacementStyleValue::create(CSS::GridTrackPlacement(static_cast<int>(current_token.number_value())));
+        if (is_line_name(current_token))
+            return GridTrackPlacementStyleValue::create(CSS::GridTrackPlacement(current_token.ident()));
         return {};
     }
 
     auto span_value = false;
     auto span_or_position_value = 0;
+    String line_name_value;
     while (true) {
         if (is_auto(current_token))
             return {};
@@ -5686,6 +5696,12 @@ RefPtr<StyleValue> Parser::parse_grid_track_placement(Vector<ComponentValue> con
             else
                 return {};
         }
+        if (is_line_name(current_token)) {
+            if (line_name_value.is_empty())
+                line_name_value = current_token.ident();
+            else
+                return {};
+        }
         tokens.skip_whitespace();
         if (tokens.has_next_token())
             current_token = tokens.next_token().token();
@@ -5700,6 +5716,9 @@ RefPtr<StyleValue> Parser::parse_grid_track_placement(Vector<ComponentValue> con
     // If the <integer> is omitted, it defaults to 1.
     if (span_or_position_value == 0)
         span_or_position_value = 1;
+
+    if (!line_name_value.is_empty())
+        return GridTrackPlacementStyleValue::create(CSS::GridTrackPlacement(line_name_value, span_or_position_value, span_value));
     return GridTrackPlacementStyleValue::create(CSS::GridTrackPlacement(span_or_position_value, span_value));
 }