From d461e96f40030c5d21efcbe9fb2c35c9fa591d48 Mon Sep 17 00:00:00 2001
From: Sam Atkins <sam@ladybird.org>
Date: Thu, 28 Aug 2025 10:29:57 +0100
Subject: [PATCH] LibWeb/CSS: Make :heading() pseudo-class take integers not
 AN+B

Corresponds to https://github.com/w3c/csswg-drafts/commit/8eb3787e34fff15b12b110e2492aa414d82ef965
---
 .../LibWeb/CSS/Parser/SelectorParsing.cpp     |  43 ++++++
 Libraries/LibWeb/CSS/PseudoClasses.json       |   2 +-
 Libraries/LibWeb/CSS/Selector.cpp             |   6 +-
 Libraries/LibWeb/CSS/Selector.h               |   3 +
 Libraries/LibWeb/CSS/SelectorEngine.cpp       |  11 +-
 Libraries/LibWeb/Dump.cpp                     |   6 +
 .../LibWeb/GenerateCSSPseudoClass.cpp         |   3 +
 .../wpt-import/css/selectors/heading.txt      | 132 +-----------------
 .../css/selectors/parsing/parse-heading.txt   |  25 ++--
 .../wpt-import/css/selectors/heading.html     |   9 --
 10 files changed, 79 insertions(+), 161 deletions(-)

diff --git a/Libraries/LibWeb/CSS/Parser/SelectorParsing.cpp b/Libraries/LibWeb/CSS/Parser/SelectorParsing.cpp
index 2883b4c38fb..673e3247711 100644
--- a/Libraries/LibWeb/CSS/Parser/SelectorParsing.cpp
+++ b/Libraries/LibWeb/CSS/Parser/SelectorParsing.cpp
@@ -899,6 +899,49 @@ Parser::ParseErrorOr<Selector::SimpleSelector> Parser::parse_pseudo_simple_selec
                     .languages = move(languages) }
             };
         }
+        case PseudoClassMetadata::ParameterType::LevelList: {
+            // https://drafts.csswg.org/selectors-5/#heading-functional-pseudo
+            // :heading() = :heading( <level># )
+            // where <level> is a <number-token> with its type flag set to "integer".
+            Vector<i64> levels;
+            auto function_token_stream = TokenStream(pseudo_function.value);
+            auto level_lists = parse_a_comma_separated_list_of_component_values(function_token_stream);
+
+            for (auto const& level_tokens : level_lists) {
+                TokenStream level_token_stream { level_tokens };
+                level_token_stream.discard_whitespace();
+                auto& maybe_integer = level_token_stream.consume_a_token();
+                level_token_stream.discard_whitespace();
+
+                if (!maybe_integer.is(Token::Type::Number) || !maybe_integer.token().number().is_integer()) {
+                    ErrorReporter::the().report(InvalidPseudoClassOrElementError {
+                        .name = MUST(String::formatted(":{}", pseudo_function.name)),
+                        .value_string = pseudo_class_token.to_string(),
+                        .description = "Failed to parse argument as a <level>: Not an <integer> literal."_string,
+                    });
+                    return ParseError::SyntaxError;
+                }
+
+                if (level_token_stream.has_next_token()) {
+                    ErrorReporter::the().report(InvalidPseudoClassOrElementError {
+                        .name = MUST(String::formatted(":{}", pseudo_function.name)),
+                        .value_string = pseudo_class_token.to_string(),
+                        .description = "Failed to parse argument as a <level>: Has trailing tokens."_string,
+                    });
+                    return ParseError::SyntaxError;
+                }
+
+                levels.append(maybe_integer.token().number().integer_value());
+            }
+
+            return Selector::SimpleSelector {
+                .type = Selector::SimpleSelector::Type::PseudoClass,
+                .value = Selector::SimpleSelector::PseudoClassSelector {
+                    .type = pseudo_class,
+                    .levels = move(levels),
+                }
+            };
+        }
         case PseudoClassMetadata::ParameterType::RelativeSelectorList:
         case PseudoClassMetadata::ParameterType::SelectorList: {
             auto function_token_stream = TokenStream(pseudo_function.value);
diff --git a/Libraries/LibWeb/CSS/PseudoClasses.json b/Libraries/LibWeb/CSS/PseudoClasses.json
index 4048796dddb..d4e2d8cac9b 100644
--- a/Libraries/LibWeb/CSS/PseudoClasses.json
+++ b/Libraries/LibWeb/CSS/PseudoClasses.json
@@ -51,7 +51,7 @@
     "argument": "<relative-selector-list>"
   },
   "heading": {
-    "argument": "<an+b>#?"
+    "argument": "<level>#?"
   },
   "high-value": {
     "argument": ""
diff --git a/Libraries/LibWeb/CSS/Selector.cpp b/Libraries/LibWeb/CSS/Selector.cpp
index 4f2a99d2a30..d4d4eb354f8 100644
--- a/Libraries/LibWeb/CSS/Selector.cpp
+++ b/Libraries/LibWeb/CSS/Selector.cpp
@@ -435,7 +435,7 @@ String Selector::SimpleSelector::serialize() const
             // For pseudo-classes with both a function and identifier form, see if they have arguments.
             switch (pseudo_class.type) {
             case PseudoClass::Heading:
-                return !pseudo_class.an_plus_b_patterns.is_empty();
+                return !pseudo_class.levels.is_empty();
             case PseudoClass::Host:
                 return !pseudo_class.argument_selector_list.is_empty();
             default:
@@ -484,6 +484,10 @@ String Selector::SimpleSelector::serialize() const
                 // The serialization of a comma-separated list of each argument’s serialization as a string, preserving relative order.
                 s.join(", "sv, pseudo_class.languages);
                 break;
+            case PseudoClassMetadata::ParameterType::LevelList:
+                // AD-HOC: not in the spec.
+                s.join(", "sv, pseudo_class.levels);
+                break;
             }
             s.append(')');
         }
diff --git a/Libraries/LibWeb/CSS/Selector.h b/Libraries/LibWeb/CSS/Selector.h
index 1f6860f77c4..8a908f2b0d6 100644
--- a/Libraries/LibWeb/CSS/Selector.h
+++ b/Libraries/LibWeb/CSS/Selector.h
@@ -109,6 +109,9 @@ public:
                 FlyString string_value;
             };
             Optional<Ident> ident {};
+
+            // Used by :heading()
+            Vector<i64> levels {};
         };
 
         struct Name {
diff --git a/Libraries/LibWeb/CSS/SelectorEngine.cpp b/Libraries/LibWeb/CSS/SelectorEngine.cpp
index ad768939dee..f6978eb6c8b 100644
--- a/Libraries/LibWeb/CSS/SelectorEngine.cpp
+++ b/Libraries/LibWeb/CSS/SelectorEngine.cpp
@@ -1037,7 +1037,7 @@ static inline bool matches_pseudo_class(CSS::Selector::SimpleSelector::PseudoCla
         // The :heading pseudo-class must match all h1, h2, h3, h4, h5, and h6 elements.
 
         // https://html.spec.whatwg.org/multipage/semantics-other.html#selector-heading-functional
-        // The :heading(An+B#) pseudo-class must match all h1, h2, h3, h4, h5, and h6 elements that have a heading level among An+B. [CSSSYNTAX] [CSSVALUES]
+        // The :heading(integer#) pseudo-class must match all h1, h2, h3, h4, h5, and h6 elements that have a heading level of integer. [CSSSYNTAX] [CSSVALUES]
 
         // NB: We combine the "is this an h* element?" and "what is it's level?" checks together here.
         if (!element.is_html_element())
@@ -1061,15 +1061,10 @@ static inline bool matches_pseudo_class(CSS::Selector::SimpleSelector::PseudoCla
         if (!heading_level.has_value())
             return false;
 
-        if (pseudo_class.an_plus_b_patterns.is_empty())
+        if (pseudo_class.levels.is_empty())
             return true;
 
-        for (auto const& an_plus_b_pattern : pseudo_class.an_plus_b_patterns) {
-            if (an_plus_b_pattern.matches(heading_level.value()))
-                return true;
-        }
-
-        return false;
+        return pseudo_class.levels.contains_slow(heading_level.value());
     }
     }
 
diff --git a/Libraries/LibWeb/Dump.cpp b/Libraries/LibWeb/Dump.cpp
index b9ebcd7f69f..ce9bcca9165 100644
--- a/Libraries/LibWeb/Dump.cpp
+++ b/Libraries/LibWeb/Dump.cpp
@@ -598,6 +598,12 @@ void dump_selector(StringBuilder& builder, CSS::Selector const& selector, int in
                     builder.append(')');
                     break;
                 }
+                case CSS::PseudoClassMetadata::ParameterType::LevelList: {
+                    builder.append('(');
+                    builder.join(',', pseudo_class.levels);
+                    builder.append(')');
+                    break;
+                }
                 }
             }
 
diff --git a/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateCSSPseudoClass.cpp b/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateCSSPseudoClass.cpp
index 1bf225a9d3c..53ba1e031d7 100644
--- a/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateCSSPseudoClass.cpp
+++ b/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateCSSPseudoClass.cpp
@@ -77,6 +77,7 @@ struct PseudoClassMetadata {
         ForgivingRelativeSelectorList,
         Ident,
         LanguageRanges,
+        LevelList,
         RelativeSelectorList,
         SelectorList,
     } parameter_type;
@@ -183,6 +184,8 @@ PseudoClassMetadata pseudo_class_metadata(PseudoClass pseudo_class)
                 parameter_type = "Ident"_string;
             } else if (argument_string == "<language-ranges>"sv) {
                 parameter_type = "LanguageRanges"_string;
+            } else if (argument_string == "<level>#"sv) {
+                parameter_type = "LevelList"_string;
             } else if (argument_string == "<relative-selector-list>"sv) {
                 parameter_type = "RelativeSelectorList"_string;
             } else if (argument_string == "<selector-list>"sv) {
diff --git a/Tests/LibWeb/Text/expected/wpt-import/css/selectors/heading.txt b/Tests/LibWeb/Text/expected/wpt-import/css/selectors/heading.txt
index ac3cfcad8d7..524054c835f 100644
--- a/Tests/LibWeb/Text/expected/wpt-import/css/selectors/heading.txt
+++ b/Tests/LibWeb/Text/expected/wpt-import/css/selectors/heading.txt
@@ -1,8 +1,8 @@
 Harness status: OK
 
-Found 308 tests
+Found 182 tests
 
-308 Pass
+182 Pass
 Pass	<h1 data-expect-match="1"></h1> :heading
 Pass	<h1 data-expect-match="1"></h1> :heading(1)
 Pass	<h1 data-expect-match="1"></h1> :heading(2)
@@ -14,17 +14,8 @@ Pass	<h1 data-expect-match="1"></h1> :heading(7)
 Pass	<h1 data-expect-match="1"></h1> :heading(8)
 Pass	<h1 data-expect-match="1"></h1> :heading(9)
 Pass	<h1 data-expect-match="1"></h1> :heading(0)
-Pass	<h1 data-expect-match="1"></h1> :heading(-1)
 Pass	<h1 data-expect-match="1"></h1> :heading(0, 1, 2)
 Pass	<h1 data-expect-match="1"></h1> :heading(6, 7)
-Pass	<h1 data-expect-match="1"></h1> :heading(n)
-Pass	<h1 data-expect-match="1"></h1> :heading(2n)
-Pass	<h1 data-expect-match="1"></h1> :heading(2n+1)
-Pass	<h1 data-expect-match="1"></h1> :heading(2n+2)
-Pass	<h1 data-expect-match="1"></h1> :heading(-n+3)
-Pass	<h1 data-expect-match="1"></h1> :heading(2n, 3n)
-Pass	<h1 data-expect-match="1"></h1> :heading(even)
-Pass	<h1 data-expect-match="1"></h1> :heading(odd)
 Pass	<h2 data-expect-match="2"></h2> :heading
 Pass	<h2 data-expect-match="2"></h2> :heading(1)
 Pass	<h2 data-expect-match="2"></h2> :heading(2)
@@ -36,17 +27,8 @@ Pass	<h2 data-expect-match="2"></h2> :heading(7)
 Pass	<h2 data-expect-match="2"></h2> :heading(8)
 Pass	<h2 data-expect-match="2"></h2> :heading(9)
 Pass	<h2 data-expect-match="2"></h2> :heading(0)
-Pass	<h2 data-expect-match="2"></h2> :heading(-1)
 Pass	<h2 data-expect-match="2"></h2> :heading(0, 1, 2)
 Pass	<h2 data-expect-match="2"></h2> :heading(6, 7)
-Pass	<h2 data-expect-match="2"></h2> :heading(n)
-Pass	<h2 data-expect-match="2"></h2> :heading(2n)
-Pass	<h2 data-expect-match="2"></h2> :heading(2n+1)
-Pass	<h2 data-expect-match="2"></h2> :heading(2n+2)
-Pass	<h2 data-expect-match="2"></h2> :heading(-n+3)
-Pass	<h2 data-expect-match="2"></h2> :heading(2n, 3n)
-Pass	<h2 data-expect-match="2"></h2> :heading(even)
-Pass	<h2 data-expect-match="2"></h2> :heading(odd)
 Pass	<h3 data-expect-match="3"></h3> :heading
 Pass	<h3 data-expect-match="3"></h3> :heading(1)
 Pass	<h3 data-expect-match="3"></h3> :heading(2)
@@ -58,17 +40,8 @@ Pass	<h3 data-expect-match="3"></h3> :heading(7)
 Pass	<h3 data-expect-match="3"></h3> :heading(8)
 Pass	<h3 data-expect-match="3"></h3> :heading(9)
 Pass	<h3 data-expect-match="3"></h3> :heading(0)
-Pass	<h3 data-expect-match="3"></h3> :heading(-1)
 Pass	<h3 data-expect-match="3"></h3> :heading(0, 1, 2)
 Pass	<h3 data-expect-match="3"></h3> :heading(6, 7)
-Pass	<h3 data-expect-match="3"></h3> :heading(n)
-Pass	<h3 data-expect-match="3"></h3> :heading(2n)
-Pass	<h3 data-expect-match="3"></h3> :heading(2n+1)
-Pass	<h3 data-expect-match="3"></h3> :heading(2n+2)
-Pass	<h3 data-expect-match="3"></h3> :heading(-n+3)
-Pass	<h3 data-expect-match="3"></h3> :heading(2n, 3n)
-Pass	<h3 data-expect-match="3"></h3> :heading(even)
-Pass	<h3 data-expect-match="3"></h3> :heading(odd)
 Pass	<h4 data-expect-match="4"></h4> :heading
 Pass	<h4 data-expect-match="4"></h4> :heading(1)
 Pass	<h4 data-expect-match="4"></h4> :heading(2)
@@ -80,17 +53,8 @@ Pass	<h4 data-expect-match="4"></h4> :heading(7)
 Pass	<h4 data-expect-match="4"></h4> :heading(8)
 Pass	<h4 data-expect-match="4"></h4> :heading(9)
 Pass	<h4 data-expect-match="4"></h4> :heading(0)
-Pass	<h4 data-expect-match="4"></h4> :heading(-1)
 Pass	<h4 data-expect-match="4"></h4> :heading(0, 1, 2)
 Pass	<h4 data-expect-match="4"></h4> :heading(6, 7)
-Pass	<h4 data-expect-match="4"></h4> :heading(n)
-Pass	<h4 data-expect-match="4"></h4> :heading(2n)
-Pass	<h4 data-expect-match="4"></h4> :heading(2n+1)
-Pass	<h4 data-expect-match="4"></h4> :heading(2n+2)
-Pass	<h4 data-expect-match="4"></h4> :heading(-n+3)
-Pass	<h4 data-expect-match="4"></h4> :heading(2n, 3n)
-Pass	<h4 data-expect-match="4"></h4> :heading(even)
-Pass	<h4 data-expect-match="4"></h4> :heading(odd)
 Pass	<h5 data-expect-match="5"></h5> :heading
 Pass	<h5 data-expect-match="5"></h5> :heading(1)
 Pass	<h5 data-expect-match="5"></h5> :heading(2)
@@ -102,17 +66,8 @@ Pass	<h5 data-expect-match="5"></h5> :heading(7)
 Pass	<h5 data-expect-match="5"></h5> :heading(8)
 Pass	<h5 data-expect-match="5"></h5> :heading(9)
 Pass	<h5 data-expect-match="5"></h5> :heading(0)
-Pass	<h5 data-expect-match="5"></h5> :heading(-1)
 Pass	<h5 data-expect-match="5"></h5> :heading(0, 1, 2)
 Pass	<h5 data-expect-match="5"></h5> :heading(6, 7)
-Pass	<h5 data-expect-match="5"></h5> :heading(n)
-Pass	<h5 data-expect-match="5"></h5> :heading(2n)
-Pass	<h5 data-expect-match="5"></h5> :heading(2n+1)
-Pass	<h5 data-expect-match="5"></h5> :heading(2n+2)
-Pass	<h5 data-expect-match="5"></h5> :heading(-n+3)
-Pass	<h5 data-expect-match="5"></h5> :heading(2n, 3n)
-Pass	<h5 data-expect-match="5"></h5> :heading(even)
-Pass	<h5 data-expect-match="5"></h5> :heading(odd)
 Pass	<h6 data-expect-match="6"></h6> :heading
 Pass	<h6 data-expect-match="6"></h6> :heading(1)
 Pass	<h6 data-expect-match="6"></h6> :heading(2)
@@ -124,17 +79,8 @@ Pass	<h6 data-expect-match="6"></h6> :heading(7)
 Pass	<h6 data-expect-match="6"></h6> :heading(8)
 Pass	<h6 data-expect-match="6"></h6> :heading(9)
 Pass	<h6 data-expect-match="6"></h6> :heading(0)
-Pass	<h6 data-expect-match="6"></h6> :heading(-1)
 Pass	<h6 data-expect-match="6"></h6> :heading(0, 1, 2)
 Pass	<h6 data-expect-match="6"></h6> :heading(6, 7)
-Pass	<h6 data-expect-match="6"></h6> :heading(n)
-Pass	<h6 data-expect-match="6"></h6> :heading(2n)
-Pass	<h6 data-expect-match="6"></h6> :heading(2n+1)
-Pass	<h6 data-expect-match="6"></h6> :heading(2n+2)
-Pass	<h6 data-expect-match="6"></h6> :heading(-n+3)
-Pass	<h6 data-expect-match="6"></h6> :heading(2n, 3n)
-Pass	<h6 data-expect-match="6"></h6> :heading(even)
-Pass	<h6 data-expect-match="6"></h6> :heading(odd)
 Pass	<h7 data-expect-match=""></h7> :heading
 Pass	<h7 data-expect-match=""></h7> :heading(1)
 Pass	<h7 data-expect-match=""></h7> :heading(2)
@@ -146,17 +92,8 @@ Pass	<h7 data-expect-match=""></h7> :heading(7)
 Pass	<h7 data-expect-match=""></h7> :heading(8)
 Pass	<h7 data-expect-match=""></h7> :heading(9)
 Pass	<h7 data-expect-match=""></h7> :heading(0)
-Pass	<h7 data-expect-match=""></h7> :heading(-1)
 Pass	<h7 data-expect-match=""></h7> :heading(0, 1, 2)
 Pass	<h7 data-expect-match=""></h7> :heading(6, 7)
-Pass	<h7 data-expect-match=""></h7> :heading(n)
-Pass	<h7 data-expect-match=""></h7> :heading(2n)
-Pass	<h7 data-expect-match=""></h7> :heading(2n+1)
-Pass	<h7 data-expect-match=""></h7> :heading(2n+2)
-Pass	<h7 data-expect-match=""></h7> :heading(-n+3)
-Pass	<h7 data-expect-match=""></h7> :heading(2n, 3n)
-Pass	<h7 data-expect-match=""></h7> :heading(even)
-Pass	<h7 data-expect-match=""></h7> :heading(odd)
 Pass	<h8 data-expect-match=""></h8> :heading
 Pass	<h8 data-expect-match=""></h8> :heading(1)
 Pass	<h8 data-expect-match=""></h8> :heading(2)
@@ -168,17 +105,8 @@ Pass	<h8 data-expect-match=""></h8> :heading(7)
 Pass	<h8 data-expect-match=""></h8> :heading(8)
 Pass	<h8 data-expect-match=""></h8> :heading(9)
 Pass	<h8 data-expect-match=""></h8> :heading(0)
-Pass	<h8 data-expect-match=""></h8> :heading(-1)
 Pass	<h8 data-expect-match=""></h8> :heading(0, 1, 2)
 Pass	<h8 data-expect-match=""></h8> :heading(6, 7)
-Pass	<h8 data-expect-match=""></h8> :heading(n)
-Pass	<h8 data-expect-match=""></h8> :heading(2n)
-Pass	<h8 data-expect-match=""></h8> :heading(2n+1)
-Pass	<h8 data-expect-match=""></h8> :heading(2n+2)
-Pass	<h8 data-expect-match=""></h8> :heading(-n+3)
-Pass	<h8 data-expect-match=""></h8> :heading(2n, 3n)
-Pass	<h8 data-expect-match=""></h8> :heading(even)
-Pass	<h8 data-expect-match=""></h8> :heading(odd)
 Pass	<h9 data-expect-match=""></h9> :heading
 Pass	<h9 data-expect-match=""></h9> :heading(1)
 Pass	<h9 data-expect-match=""></h9> :heading(2)
@@ -190,17 +118,8 @@ Pass	<h9 data-expect-match=""></h9> :heading(7)
 Pass	<h9 data-expect-match=""></h9> :heading(8)
 Pass	<h9 data-expect-match=""></h9> :heading(9)
 Pass	<h9 data-expect-match=""></h9> :heading(0)
-Pass	<h9 data-expect-match=""></h9> :heading(-1)
 Pass	<h9 data-expect-match=""></h9> :heading(0, 1, 2)
 Pass	<h9 data-expect-match=""></h9> :heading(6, 7)
-Pass	<h9 data-expect-match=""></h9> :heading(n)
-Pass	<h9 data-expect-match=""></h9> :heading(2n)
-Pass	<h9 data-expect-match=""></h9> :heading(2n+1)
-Pass	<h9 data-expect-match=""></h9> :heading(2n+2)
-Pass	<h9 data-expect-match=""></h9> :heading(-n+3)
-Pass	<h9 data-expect-match=""></h9> :heading(2n, 3n)
-Pass	<h9 data-expect-match=""></h9> :heading(even)
-Pass	<h9 data-expect-match=""></h9> :heading(odd)
 Pass	<h0 data-expect-match=""></h0> :heading
 Pass	<h0 data-expect-match=""></h0> :heading(1)
 Pass	<h0 data-expect-match=""></h0> :heading(2)
@@ -212,17 +131,8 @@ Pass	<h0 data-expect-match=""></h0> :heading(7)
 Pass	<h0 data-expect-match=""></h0> :heading(8)
 Pass	<h0 data-expect-match=""></h0> :heading(9)
 Pass	<h0 data-expect-match=""></h0> :heading(0)
-Pass	<h0 data-expect-match=""></h0> :heading(-1)
 Pass	<h0 data-expect-match=""></h0> :heading(0, 1, 2)
 Pass	<h0 data-expect-match=""></h0> :heading(6, 7)
-Pass	<h0 data-expect-match=""></h0> :heading(n)
-Pass	<h0 data-expect-match=""></h0> :heading(2n)
-Pass	<h0 data-expect-match=""></h0> :heading(2n+1)
-Pass	<h0 data-expect-match=""></h0> :heading(2n+2)
-Pass	<h0 data-expect-match=""></h0> :heading(-n+3)
-Pass	<h0 data-expect-match=""></h0> :heading(2n, 3n)
-Pass	<h0 data-expect-match=""></h0> :heading(even)
-Pass	<h0 data-expect-match=""></h0> :heading(odd)
 Pass	<h1 data-expect-match="1" aria-level="2"></h1> :heading
 Pass	<h1 data-expect-match="1" aria-level="2"></h1> :heading(1)
 Pass	<h1 data-expect-match="1" aria-level="2"></h1> :heading(2)
@@ -234,17 +144,8 @@ Pass	<h1 data-expect-match="1" aria-level="2"></h1> :heading(7)
 Pass	<h1 data-expect-match="1" aria-level="2"></h1> :heading(8)
 Pass	<h1 data-expect-match="1" aria-level="2"></h1> :heading(9)
 Pass	<h1 data-expect-match="1" aria-level="2"></h1> :heading(0)
-Pass	<h1 data-expect-match="1" aria-level="2"></h1> :heading(-1)
 Pass	<h1 data-expect-match="1" aria-level="2"></h1> :heading(0, 1, 2)
 Pass	<h1 data-expect-match="1" aria-level="2"></h1> :heading(6, 7)
-Pass	<h1 data-expect-match="1" aria-level="2"></h1> :heading(n)
-Pass	<h1 data-expect-match="1" aria-level="2"></h1> :heading(2n)
-Pass	<h1 data-expect-match="1" aria-level="2"></h1> :heading(2n+1)
-Pass	<h1 data-expect-match="1" aria-level="2"></h1> :heading(2n+2)
-Pass	<h1 data-expect-match="1" aria-level="2"></h1> :heading(-n+3)
-Pass	<h1 data-expect-match="1" aria-level="2"></h1> :heading(2n, 3n)
-Pass	<h1 data-expect-match="1" aria-level="2"></h1> :heading(even)
-Pass	<h1 data-expect-match="1" aria-level="2"></h1> :heading(odd)
 Pass	<h1 data-expect-match="1"></h1> in section :heading
 Pass	<h1 data-expect-match="1"></h1> in section :heading(1)
 Pass	<h1 data-expect-match="1"></h1> in section :heading(2)
@@ -256,17 +157,8 @@ Pass	<h1 data-expect-match="1"></h1> in section :heading(7)
 Pass	<h1 data-expect-match="1"></h1> in section :heading(8)
 Pass	<h1 data-expect-match="1"></h1> in section :heading(9)
 Pass	<h1 data-expect-match="1"></h1> in section :heading(0)
-Pass	<h1 data-expect-match="1"></h1> in section :heading(-1)
 Pass	<h1 data-expect-match="1"></h1> in section :heading(0, 1, 2)
 Pass	<h1 data-expect-match="1"></h1> in section :heading(6, 7)
-Pass	<h1 data-expect-match="1"></h1> in section :heading(n)
-Pass	<h1 data-expect-match="1"></h1> in section :heading(2n)
-Pass	<h1 data-expect-match="1"></h1> in section :heading(2n+1)
-Pass	<h1 data-expect-match="1"></h1> in section :heading(2n+2)
-Pass	<h1 data-expect-match="1"></h1> in section :heading(-n+3)
-Pass	<h1 data-expect-match="1"></h1> in section :heading(2n, 3n)
-Pass	<h1 data-expect-match="1"></h1> in section :heading(even)
-Pass	<h1 data-expect-match="1"></h1> in section :heading(odd)
 Pass	<hgroup data-expect-match=""></hgroup> :heading
 Pass	<hgroup data-expect-match=""></hgroup> :heading(1)
 Pass	<hgroup data-expect-match=""></hgroup> :heading(2)
@@ -278,17 +170,8 @@ Pass	<hgroup data-expect-match=""></hgroup> :heading(7)
 Pass	<hgroup data-expect-match=""></hgroup> :heading(8)
 Pass	<hgroup data-expect-match=""></hgroup> :heading(9)
 Pass	<hgroup data-expect-match=""></hgroup> :heading(0)
-Pass	<hgroup data-expect-match=""></hgroup> :heading(-1)
 Pass	<hgroup data-expect-match=""></hgroup> :heading(0, 1, 2)
 Pass	<hgroup data-expect-match=""></hgroup> :heading(6, 7)
-Pass	<hgroup data-expect-match=""></hgroup> :heading(n)
-Pass	<hgroup data-expect-match=""></hgroup> :heading(2n)
-Pass	<hgroup data-expect-match=""></hgroup> :heading(2n+1)
-Pass	<hgroup data-expect-match=""></hgroup> :heading(2n+2)
-Pass	<hgroup data-expect-match=""></hgroup> :heading(-n+3)
-Pass	<hgroup data-expect-match=""></hgroup> :heading(2n, 3n)
-Pass	<hgroup data-expect-match=""></hgroup> :heading(even)
-Pass	<hgroup data-expect-match=""></hgroup> :heading(odd)
 Pass	<p role="heading" aria-level="1" data-expect-match=""></p> :heading
 Pass	<p role="heading" aria-level="1" data-expect-match=""></p> :heading(1)
 Pass	<p role="heading" aria-level="1" data-expect-match=""></p> :heading(2)
@@ -300,14 +183,5 @@ Pass	<p role="heading" aria-level="1" data-expect-match=""></p> :heading(7)
 Pass	<p role="heading" aria-level="1" data-expect-match=""></p> :heading(8)
 Pass	<p role="heading" aria-level="1" data-expect-match=""></p> :heading(9)
 Pass	<p role="heading" aria-level="1" data-expect-match=""></p> :heading(0)
-Pass	<p role="heading" aria-level="1" data-expect-match=""></p> :heading(-1)
 Pass	<p role="heading" aria-level="1" data-expect-match=""></p> :heading(0, 1, 2)
-Pass	<p role="heading" aria-level="1" data-expect-match=""></p> :heading(6, 7)
-Pass	<p role="heading" aria-level="1" data-expect-match=""></p> :heading(n)
-Pass	<p role="heading" aria-level="1" data-expect-match=""></p> :heading(2n)
-Pass	<p role="heading" aria-level="1" data-expect-match=""></p> :heading(2n+1)
-Pass	<p role="heading" aria-level="1" data-expect-match=""></p> :heading(2n+2)
-Pass	<p role="heading" aria-level="1" data-expect-match=""></p> :heading(-n+3)
-Pass	<p role="heading" aria-level="1" data-expect-match=""></p> :heading(2n, 3n)
-Pass	<p role="heading" aria-level="1" data-expect-match=""></p> :heading(even)
-Pass	<p role="heading" aria-level="1" data-expect-match=""></p> :heading(odd)
\ No newline at end of file
+Pass	<p role="heading" aria-level="1" data-expect-match=""></p> :heading(6, 7)
\ No newline at end of file
diff --git a/Tests/LibWeb/Text/expected/wpt-import/css/selectors/parsing/parse-heading.txt b/Tests/LibWeb/Text/expected/wpt-import/css/selectors/parsing/parse-heading.txt
index 6baa7303344..51cc9791663 100644
--- a/Tests/LibWeb/Text/expected/wpt-import/css/selectors/parsing/parse-heading.txt
+++ b/Tests/LibWeb/Text/expected/wpt-import/css/selectors/parsing/parse-heading.txt
@@ -2,8 +2,7 @@ Harness status: OK
 
 Found 28 tests
 
-17 Pass
-11 Fail
+28 Pass
 Pass	":heading" should be a valid selector
 Pass	":heading(2)" should be a valid selector
 Pass	":heading(99999)" should be a valid selector
@@ -17,17 +16,17 @@ Pass	"h1:heading(2)" should be a valid selector
 Pass	":heading()" should be an invalid selector
 Pass	":heading(1.0)" should be an invalid selector
 Pass	":heading(1.4)" should be an invalid selector
-Fail	":heading(n)" should be an invalid selector
-Fail	":heading(odd)" should be an invalid selector
-Fail	":heading(even)" should be an invalid selector
-Fail	":heading(2n)" should be an invalid selector
-Fail	":heading(2n+1)" should be an invalid selector
-Fail	":heading(2n+2)" should be an invalid selector
-Fail	":heading(-n+3)" should be an invalid selector
-Fail	":heading(2n, 3n)" should be an invalid selector
-Fail	":heading(2, 3n)" should be an invalid selector
-Fail	":heading(2 of .foo)" should be an invalid selector
-Fail	":heading(2n of .foo)" should be an invalid selector
+Pass	":heading(n)" should be an invalid selector
+Pass	":heading(odd)" should be an invalid selector
+Pass	":heading(even)" should be an invalid selector
+Pass	":heading(2n)" should be an invalid selector
+Pass	":heading(2n+1)" should be an invalid selector
+Pass	":heading(2n+2)" should be an invalid selector
+Pass	":heading(-n+3)" should be an invalid selector
+Pass	":heading(2n, 3n)" should be an invalid selector
+Pass	":heading(2, 3n)" should be an invalid selector
+Pass	":heading(2 of .foo)" should be an invalid selector
+Pass	":heading(2n of .foo)" should be an invalid selector
 Pass	":heading(calc(1))" should be an invalid selector
 Pass	":heading(max(1, 2))" should be an invalid selector
 Pass	":heading(min(1, 2)" should be an invalid selector
diff --git a/Tests/LibWeb/Text/input/wpt-import/css/selectors/heading.html b/Tests/LibWeb/Text/input/wpt-import/css/selectors/heading.html
index 5165474b2ff..d303a5bc21e 100644
--- a/Tests/LibWeb/Text/input/wpt-import/css/selectors/heading.html
+++ b/Tests/LibWeb/Text/input/wpt-import/css/selectors/heading.html
@@ -33,17 +33,8 @@ const tests = [
   {args: ['8'], match: []},
   {args: ['9'], match: []},
   {args: ['0'], match: []},
-  {args: ['-1'], match: []},
   {args: ['0', '1', '2'], match: [1, 2]},
   {args: ['6', '7'], match: [6]},
-  {args: ['n'], match: [1, 2, 3, 4, 5, 6]},
-  {args: ['2n'], match: [2, 4, 6]},
-  {args: ['2n+1'], match: [1, 3, 5]},
-  {args: ['2n+2'], match: [2, 4, 6]},
-  {args: ['-n+3'], match: [1, 2, 3]},
-  {args: ['2n', '3n'], match: [2, 3, 4, 6]},
-  {args: ['even'], match: [2, 4, 6]},
-  {args: ['odd'], match: [1, 3, 5]},
 ];
 for (const el of els) {
   const testName = el.outerHTML + (el.parentNode === document.body ? '' : ' in ' + el.parentNode.localName);