LibWeb: Define if identifier represent area or line during layout [GFC]

This fixes regression introduced in
c03e025a32 by assuming that it is
possible to determine whether identifier stands for line or area
during parsing.

Userland/Libraries/LibWeb/CSS/GridTrackPlacement.cpp

@@ -17,13 +17,15 @@ String GridTrackPlacement::to_string() const
         [&](Auto const&) {
             builder.append("auto"sv);
         },
-        [&](Area const& area) {
-            builder.append(area.name);
-        },
-        [&](Line const& line) {
-            builder.appendff("{}", line.value);
-            if (line.name.has_value())
-                builder.appendff(" {}", line.name.value());
+        [&](AreaOrLine const& area_or_line) {
+            if (area_or_line.line_number.has_value() && area_or_line.name.has_value()) {
+                builder.appendff("{} {}", *area_or_line.line_number, *area_or_line.name);
+            } else if (area_or_line.line_number.has_value()) {
+                builder.appendff("{}", *area_or_line.line_number);
+            }
+            if (area_or_line.name.has_value()) {
+                builder.appendff("{}", *area_or_line.name);
+            }
         },
         [&](Span const& span) {
             builder.appendff("span {}", span.value);

Userland/Libraries/LibWeb/CSS/GridTrackPlacement.h

@@ -18,14 +18,9 @@ public:
         return GridTrackPlacement();
     }
 
-    static GridTrackPlacement make_area(String name)
+    static GridTrackPlacement make_line(Optional<int> line_number, Optional<String> name)
     {
-        return GridTrackPlacement(Area { .name = name });
-    }
-
-    static GridTrackPlacement make_line(int value, Optional<String> name)
-    {
-        return GridTrackPlacement(Line { .value = value, .name = name });
+        return GridTrackPlacement(AreaOrLine { .line_number = line_number, .name = name });
     }
 
     static GridTrackPlacement make_span(int value)
@@ -34,21 +29,25 @@ public:
     }
 
     bool is_auto() const { return m_value.has<Auto>(); }
-    bool is_area() const { return m_value.has<Area>(); }
-    bool is_line() const { return m_value.has<Line>(); }
     bool is_span() const { return m_value.has<Span>(); }
+    bool is_area_or_line() const { return m_value.has<AreaOrLine>(); }
 
     bool is_auto_positioned() const { return is_auto() || is_span(); }
     bool is_positioned() const { return !is_auto_positioned(); }
 
-    bool has_line_name() const
+    bool has_identifier() const
     {
-        return is_line() && m_value.get<Line>().name.has_value();
+        return is_area_or_line() && m_value.get<AreaOrLine>().name.has_value();
     }
 
-    String area_name() const { return m_value.get<Area>().name; }
-    String line_name() const { return m_value.get<Line>().name.value(); }
-    int line_number() const { return m_value.get<Line>().value; }
+    bool has_line_number() const
+    {
+        return is_area_or_line() && m_value.get<AreaOrLine>().line_number.has_value();
+    }
+
+    String identifier() const { return *m_value.get<AreaOrLine>().name; }
+
+    int line_number() const { return *m_value.get<AreaOrLine>().line_number; }
     int span() const { return m_value.get<Span>().value; }
 
     String to_string() const;
@@ -60,15 +59,10 @@ private:
         bool operator==(Auto const&) const = default;
     };
 
-    struct Area {
-        String name;
-        bool operator==(Area const& other) const = default;
-    };
-
-    struct Line {
-        int value;
+    struct AreaOrLine {
+        Optional<int> line_number;
         Optional<String> name;
-        bool operator==(Line const& other) const = default;
+        bool operator==(AreaOrLine const& other) const = default;
     };
 
     struct Span {
@@ -78,14 +72,12 @@ private:
 
     GridTrackPlacement()
         : m_value(Auto {}) {};
-    GridTrackPlacement(Area value)
-        : m_value(value) {};
-    GridTrackPlacement(Line value)
+    GridTrackPlacement(AreaOrLine value)
         : m_value(value) {};
     GridTrackPlacement(Span value)
         : m_value(value) {};
 
-    Variant<Auto, Area, Line, Span> m_value;
+    Variant<Auto, AreaOrLine, Span> m_value;
 };
 
 }

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

@@ -5371,7 +5371,7 @@ RefPtr<StyleValue> Parser::parse_grid_track_placement(Vector<ComponentValue> con
         if (is_identifier(current_token)) {
             auto maybe_string = String::from_utf8(current_token.ident());
             if (!maybe_string.is_error())
-                return GridTrackPlacementStyleValue::create(GridTrackPlacement::make_area(maybe_string.value()));
+                return GridTrackPlacementStyleValue::create(GridTrackPlacement::make_line({}, maybe_string.value()));
         }
         return nullptr;
     }