From 2a2a1986ccbcffbb6589e4e7291811d774ee7e79 Mon Sep 17 00:00:00 2001
From: Sam Atkins <sam@ladybird.org>
Date: Wed, 23 Jul 2025 10:02:34 +0100
Subject: [PATCH] LibWeb/CSS: Add `dump_string()` method to TokenStream

This is to support error reporting. It's not the most elegant way of
getting the source CSS, but it works.
---
 Libraries/LibWeb/CSS/Parser/Token.h       | 8 ++++++++
 Libraries/LibWeb/CSS/Parser/TokenStream.h | 7 +++++++
 2 files changed, 15 insertions(+)

diff --git a/Libraries/LibWeb/CSS/Parser/Token.h b/Libraries/LibWeb/CSS/Parser/Token.h
index a01b5ae7034..de4c59ae39a 100644
--- a/Libraries/LibWeb/CSS/Parser/Token.h
+++ b/Libraries/LibWeb/CSS/Parser/Token.h
@@ -187,3 +187,11 @@ private:
 };
 
 }
+
+template<>
+struct AK::Formatter<Web::CSS::Parser::Token> : Formatter<StringView> {
+    ErrorOr<void> format(FormatBuilder& builder, Web::CSS::Parser::Token const& token)
+    {
+        return Formatter<StringView>::format(builder, token.to_string());
+    }
+};
diff --git a/Libraries/LibWeb/CSS/Parser/TokenStream.h b/Libraries/LibWeb/CSS/Parser/TokenStream.h
index 6c99421f5b4..f76bc8c5889 100644
--- a/Libraries/LibWeb/CSS/Parser/TokenStream.h
+++ b/Libraries/LibWeb/CSS/Parser/TokenStream.h
@@ -189,6 +189,13 @@ public:
         }
     }
 
+    String dump_string()
+    {
+        // FIXME: The whitespace is only needed because we strip it when parsing property values. Remove it here once
+        //        we stop doing that.
+        return MUST(String::join(" "sv, m_tokens));
+    }
+
 private:
     // https://drafts.csswg.org/css-syntax/#token-stream-tokens
     Span<T const> m_tokens;