From e76026372844004bc0d6a5876363093d272d4c7f Mon Sep 17 00:00:00 2001
From: Sam Atkins <atkinssj@serenityos.org>
Date: Mon, 22 Nov 2021 17:27:09 +0000
Subject: [PATCH] LibWeb: Parse CSS `<general-enclosed>`

---
 .../Libraries/LibWeb/CSS/Parser/Parser.cpp    | 22 ++++++++++++++++---
 Userland/Libraries/LibWeb/CSS/Parser/Parser.h |  6 ++---
 2 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp b/Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp
index 6248325a0f..d56ad35bd2 100644
--- a/Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp
+++ b/Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp
@@ -1111,10 +1111,26 @@ Optional<Supports::Feature> Parser::parse_supports_feature(TokenStream<StyleComp
     return {};
 }
 
-template<typename T>
-Optional<Parser::GeneralEnclosed> Parser::parse_general_enclosed(TokenStream<T>&)
+// https://www.w3.org/TR/mediaqueries-4/#typedef-general-enclosed
+Optional<GeneralEnclosed> Parser::parse_general_enclosed(TokenStream<StyleComponentValueRule>& tokens)
 {
-    // FIXME: Actually parse this! https://www.w3.org/TR/mediaqueries-5/#typedef-general-enclosed
+    tokens.skip_whitespace();
+    auto start_position = tokens.position();
+
+    auto& first_token = tokens.next_token();
+
+    // `[ <function-token> <any-value> ) ]`
+    if (first_token.is_function())
+        return GeneralEnclosed { first_token.to_string() };
+
+    // `( <ident> <any-value> )`
+    if (first_token.is_block() && first_token.block().is_paren()) {
+        auto& block = first_token.block();
+        if (!block.values().is_empty() && block.values().first().is(Token::Type::Ident))
+            return GeneralEnclosed { first_token.to_string() };
+    }
+
+    tokens.rewind_to_position(start_position);
     return {};
 }
 
diff --git a/Userland/Libraries/LibWeb/CSS/Parser/Parser.h b/Userland/Libraries/LibWeb/CSS/Parser/Parser.h
index 4f028b6053..191d5da917 100644
--- a/Userland/Libraries/LibWeb/CSS/Parser/Parser.h
+++ b/Userland/Libraries/LibWeb/CSS/Parser/Parser.h
@@ -13,6 +13,7 @@
 #include <AK/Result.h>
 #include <AK/Vector.h>
 #include <LibWeb/CSS/CSSStyleDeclaration.h>
+#include <LibWeb/CSS/GeneralEnclosed.h>
 #include <LibWeb/CSS/MediaQuery.h>
 #include <LibWeb/CSS/Parser/DeclarationOrAtRule.h>
 #include <LibWeb/CSS/Parser/StyleBlockRule.h>
@@ -170,10 +171,7 @@ private:
     template<typename T>
     [[nodiscard]] NonnullRefPtr<StyleFunctionRule> consume_a_function(TokenStream<T>&);
 
-    struct GeneralEnclosed {
-    };
-    template<typename T>
-    [[nodiscard]] Optional<GeneralEnclosed> parse_general_enclosed(TokenStream<T>&);
+    [[nodiscard]] Optional<GeneralEnclosed> parse_general_enclosed(TokenStream<StyleComponentValueRule>&);
 
     [[nodiscard]] RefPtr<CSSRule> convert_to_rule(NonnullRefPtr<StyleRule>);
     [[nodiscard]] RefPtr<PropertyOwningCSSStyleDeclaration> convert_to_declaration(NonnullRefPtr<StyleBlockRule>);