diff --git a/Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp b/Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp index 01ac4b99748..84c9bf5f42a 100644 --- a/Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp +++ b/Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp @@ -20,6 +20,8 @@ #include #include #include +#include +#include #include #include #include @@ -1245,6 +1247,46 @@ RefPtr Parser::parse_basic_shape_value(TokenStream Parser::parse_layer_name(TokenStream& tokens, AllowBlankLayerName allow_blank_layer_name) +{ + // https://drafts.csswg.org/css-cascade-5/#typedef-layer-name + // = [ '.' ]* + + // "The CSS-wide keywords are reserved for future use, and cause the rule to be invalid at parse time if used as an in the ." + auto is_valid_layer_name_part = [](auto& token) { + return token.is(Token::Type::Ident) && !is_css_wide_keyword(token.token().ident()); + }; + + auto transaction = tokens.begin_transaction(); + tokens.skip_whitespace(); + if (!tokens.has_next_token() && allow_blank_layer_name == AllowBlankLayerName::Yes) { + // No name present, just return a blank one + return FlyString(); + } + + auto& first_name_token = tokens.next_token(); + if (!is_valid_layer_name_part(first_name_token)) + return {}; + + StringBuilder builder; + builder.append(first_name_token.token().ident()); + + while (tokens.has_next_token()) { + // Repeatedly parse `'.' ` + if (!tokens.peek_token().is_delim('.')) + break; + (void)tokens.next_token(); // '.' + + auto& name_token = tokens.next_token(); + if (!is_valid_layer_name_part(name_token)) + return {}; + builder.appendff(".{}", name_token.token().ident()); + } + + transaction.commit(); + return builder.to_fly_string_without_validation(); +} + JS::GCPtr Parser::convert_to_rule(NonnullRefPtr rule) { if (rule->is_at_rule()) { @@ -1265,6 +1307,9 @@ JS::GCPtr Parser::convert_to_rule(NonnullRefPtr rule) if (rule->at_rule_name().equals_ignoring_ascii_case("keyframes"sv)) return convert_to_keyframes_rule(rule); + if (rule->at_rule_name().equals_ignoring_ascii_case("layer"sv)) + return convert_to_layer_rule(rule); + if (rule->at_rule_name().equals_ignoring_ascii_case("media"sv)) return convert_to_media_rule(rule); @@ -1357,6 +1402,75 @@ JS::GCPtr Parser::convert_to_import_rule(Rule& rule) return CSSImportRule::create(url.value(), const_cast(*m_context.document())); } +JS::GCPtr Parser::convert_to_layer_rule(Rule& rule) +{ + // https://drafts.csswg.org/css-cascade-5/#at-layer + if (rule.block()) { + // CSSLayerBlockRule + // @layer ? { + // + // } + + // First, the name + FlyString layer_name = {}; + auto prelude_tokens = TokenStream { rule.prelude() }; + if (auto maybe_name = parse_layer_name(prelude_tokens, AllowBlankLayerName::Yes); maybe_name.has_value()) { + layer_name = maybe_name.release_value(); + } else { + dbgln_if(CSS_PARSER_DEBUG, "CSSParser: @layer has invalid prelude, (not a valid layer name) prelude = {}; discarding.", rule.prelude()); + return {}; + } + + prelude_tokens.skip_whitespace(); + if (prelude_tokens.has_next_token()) { + dbgln_if(CSS_PARSER_DEBUG, "CSSParser: @layer has invalid prelude, (tokens after layer name) prelude = {}; discarding.", rule.prelude()); + return {}; + } + + // Then the rules + auto child_tokens = TokenStream { rule.block()->values() }; + auto parser_rules = parse_a_list_of_rules(child_tokens); + JS::MarkedVector child_rules(m_context.realm().heap()); + for (auto& raw_rule : parser_rules) { + if (auto child_rule = convert_to_rule(raw_rule)) + child_rules.append(child_rule); + } + auto rule_list = CSSRuleList::create(m_context.realm(), child_rules); + return CSSLayerBlockRule::create(m_context.realm(), layer_name, rule_list); + } + + // CSSLayerStatementRule + // @layer #; + auto tokens = TokenStream { rule.prelude() }; + tokens.skip_whitespace(); + Vector layer_names; + while (tokens.has_next_token()) { + // Comma + if (!layer_names.is_empty()) { + if (auto comma = tokens.next_token(); !comma.is(Token::Type::Comma)) { + dbgln_if(CSS_PARSER_DEBUG, "CSSParser: @layer missing separating comma, ({}) prelude = {}; discarding.", comma.to_debug_string(), rule.prelude()); + return {}; + } + tokens.skip_whitespace(); + } + + if (auto name = parse_layer_name(tokens, AllowBlankLayerName::No); name.has_value()) { + layer_names.append(name.release_value()); + } else { + dbgln_if(CSS_PARSER_DEBUG, "CSSParser: @layer contains invalid name, prelude = {}; discarding.", rule.prelude()); + return {}; + } + tokens.skip_whitespace(); + } + + if (layer_names.is_empty()) { + dbgln_if(CSS_PARSER_DEBUG, "CSSParser: @layer statement has no layer names, prelude = {}; discarding.", rule.prelude()); + return {}; + } + + return CSSLayerStatementRule::create(m_context.realm(), move(layer_names)); +} + JS::GCPtr Parser::convert_to_keyframes_rule(Rule& rule) { // https://www.w3.org/TR/css-animations-1/#keyframes diff --git a/Userland/Libraries/LibWeb/CSS/Parser/Parser.h b/Userland/Libraries/LibWeb/CSS/Parser/Parser.h index e9a937b9f89..e6f30c7774f 100644 --- a/Userland/Libraries/LibWeb/CSS/Parser/Parser.h +++ b/Userland/Libraries/LibWeb/CSS/Parser/Parser.h @@ -170,10 +170,17 @@ private: template Vector parse_font_face_src(TokenStream&); + enum class AllowBlankLayerName { + No, + Yes, + }; + Optional parse_layer_name(TokenStream&, AllowBlankLayerName); + JS::GCPtr convert_to_rule(NonnullRefPtr); - JS::GCPtr convert_to_media_rule(Rule&); JS::GCPtr convert_to_keyframes_rule(Rule&); JS::GCPtr convert_to_import_rule(Rule&); + JS::GCPtr convert_to_layer_rule(Rule&); + JS::GCPtr convert_to_media_rule(Rule&); JS::GCPtr convert_to_namespace_rule(Rule&); JS::GCPtr convert_to_supports_rule(Rule&);