diff options
Diffstat (limited to 'Userland/Libraries/LibWeb/CSS/Parser')
| -rw-r--r-- | Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp | 189 |
1 files changed, 110 insertions, 79 deletions
diff --git a/Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp b/Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp index 88c38d5fee..238eff596e 100644 --- a/Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp +++ b/Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp @@ -763,28 +763,24 @@ NonnullRefPtr<MediaQuery> Parser::parse_media_query(TokenStream<ComponentValue>& { // `<media-query> = <media-condition> // | [ not | only ]? <media-type> [ and <media-condition-without-or> ]?` - auto position = tokens.position(); - tokens.skip_whitespace(); // `[ not | only ]?`, Returns whether to negate the query auto parse_initial_modifier = [](auto& tokens) -> Optional<bool> { - auto position = tokens.position(); + auto transaction = tokens.begin_transaction(); tokens.skip_whitespace(); auto& token = tokens.next_token(); - - if (!token.is(Token::Type::Ident)) { - tokens.rewind_to_position(position); + if (!token.is(Token::Type::Ident)) return {}; - } auto ident = token.token().ident(); - if (ident.equals_ignoring_case("not")) { + if (ident.equals_ignoring_case("not"sv)) { + transaction.commit(); return true; } - if (ident.equals_ignoring_case("only")) { + if (ident.equals_ignoring_case("only"sv)) { + transaction.commit(); return false; } - tokens.rewind_to_position(position); return {}; }; @@ -795,7 +791,6 @@ NonnullRefPtr<MediaQuery> Parser::parse_media_query(TokenStream<ComponentValue>& dbgln("Invalid media query:"); tokens.dump_all_tokens(); } - tokens.rewind_to_position(position); return MediaQuery::create_not_all(); }; @@ -849,36 +844,38 @@ NonnullRefPtr<MediaQuery> Parser::parse_media_query(TokenStream<ComponentValue>& OwnPtr<MediaCondition> Parser::parse_media_condition(TokenStream<ComponentValue>& tokens, MediaCondition::AllowOr allow_or) { // `<media-not> | <media-in-parens> [ <media-and>* | <media-or>* ]` - auto position = tokens.position(); + auto transaction = tokens.begin_transaction(); tokens.skip_whitespace(); // `<media-not> = not <media-in-parens>` auto parse_media_not = [&](auto& tokens) -> OwnPtr<MediaCondition> { - auto position = tokens.position(); + auto local_transaction = tokens.begin_transaction(); tokens.skip_whitespace(); auto& first_token = tokens.next_token(); if (first_token.is(Token::Type::Ident) && first_token.token().ident().equals_ignoring_case("not"sv)) { - if (auto child_condition = parse_media_condition(tokens, MediaCondition::AllowOr::Yes)) + if (auto child_condition = parse_media_condition(tokens, MediaCondition::AllowOr::Yes)) { + local_transaction.commit(); return MediaCondition::from_not(child_condition.release_nonnull()); + } } - tokens.rewind_to_position(position); return {}; }; auto parse_media_with_combinator = [&](auto& tokens, StringView combinator) -> OwnPtr<MediaCondition> { - auto position = tokens.position(); + auto local_transaction = tokens.begin_transaction(); tokens.skip_whitespace(); auto& first = tokens.next_token(); if (first.is(Token::Type::Ident) && first.token().ident().equals_ignoring_case(combinator)) { tokens.skip_whitespace(); - if (auto media_in_parens = parse_media_in_parens(tokens)) + if (auto media_in_parens = parse_media_in_parens(tokens)) { + local_transaction.commit(); return media_in_parens; + } } - tokens.rewind_to_position(position); return {}; }; @@ -888,15 +885,19 @@ OwnPtr<MediaCondition> Parser::parse_media_condition(TokenStream<ComponentValue> auto parse_media_or = [&](auto& tokens) { return parse_media_with_combinator(tokens, "or"sv); }; // `<media-not>` - if (auto maybe_media_not = parse_media_not(tokens)) + if (auto maybe_media_not = parse_media_not(tokens)) { + transaction.commit(); return maybe_media_not.release_nonnull(); + } // `<media-in-parens> [ <media-and>* | <media-or>* ]` if (auto maybe_media_in_parens = parse_media_in_parens(tokens)) { tokens.skip_whitespace(); // Only `<media-in-parens>` - if (!tokens.has_next_token()) + if (!tokens.has_next_token()) { + transaction.commit(); return maybe_media_in_parens.release_nonnull(); + } NonnullOwnPtrVector<MediaCondition> child_conditions; child_conditions.append(maybe_media_in_parens.release_nonnull()); @@ -913,10 +914,10 @@ OwnPtr<MediaCondition> Parser::parse_media_condition(TokenStream<ComponentValue> continue; } // We failed - invalid syntax! - tokens.rewind_to_position(position); return {}; } + transaction.commit(); return MediaCondition::from_and_list(move(child_conditions)); } @@ -933,16 +934,15 @@ OwnPtr<MediaCondition> Parser::parse_media_condition(TokenStream<ComponentValue> continue; } // We failed - invalid syntax! - tokens.rewind_to_position(position); return {}; } + transaction.commit(); return MediaCondition::from_or_list(move(child_conditions)); } } } - tokens.rewind_to_position(position); return {}; } @@ -950,7 +950,6 @@ OwnPtr<MediaCondition> Parser::parse_media_condition(TokenStream<ComponentValue> Optional<MediaFeature> Parser::parse_media_feature(TokenStream<ComponentValue>& tokens) { // `[ <mf-plain> | <mf-boolean> | <mf-range> ]` - auto position = tokens.position(); tokens.skip_whitespace(); // `<mf-name> = <ident>` @@ -963,18 +962,19 @@ Optional<MediaFeature> Parser::parse_media_feature(TokenStream<ComponentValue>& MediaFeatureID id; }; auto parse_mf_name = [](auto& tokens, bool allow_min_max_prefix) -> Optional<MediaFeatureName> { - auto& token = tokens.peek_token(); + auto transaction = tokens.begin_transaction(); + auto& token = tokens.next_token(); if (token.is(Token::Type::Ident)) { auto name = token.token().ident(); if (auto id = media_feature_id_from_string(name); id.has_value()) { - tokens.next_token(); + transaction.commit(); return MediaFeatureName { MediaFeatureName::Type::Normal, id.value() }; } if (allow_min_max_prefix && (name.starts_with("min-", CaseSensitivity::CaseInsensitive) || name.starts_with("max-", CaseSensitivity::CaseInsensitive))) { auto adjusted_name = name.substring_view(4); if (auto id = media_feature_id_from_string(adjusted_name); id.has_value() && media_feature_type_is_range(id.value())) { - tokens.next_token(); + transaction.commit(); return MediaFeatureName { name.starts_with("min-", CaseSensitivity::CaseInsensitive) ? MediaFeatureName::Type::Min : MediaFeatureName::Type::Max, id.value() @@ -987,22 +987,23 @@ Optional<MediaFeature> Parser::parse_media_feature(TokenStream<ComponentValue>& // `<mf-boolean> = <mf-name>` auto parse_mf_boolean = [&](auto& tokens) -> Optional<MediaFeature> { - auto position = tokens.position(); + auto transaction = tokens.begin_transaction(); tokens.skip_whitespace(); if (auto maybe_name = parse_mf_name(tokens, false); maybe_name.has_value()) { tokens.skip_whitespace(); - if (!tokens.has_next_token()) + if (!tokens.has_next_token()) { + transaction.commit(); return MediaFeature::boolean(maybe_name->id); + } } - tokens.rewind_to_position(position); return {}; }; // `<mf-plain> = <mf-name> : <mf-value>` auto parse_mf_plain = [&](auto& tokens) -> Optional<MediaFeature> { - auto position = tokens.position(); + auto transaction = tokens.begin_transaction(); tokens.skip_whitespace(); if (auto maybe_name = parse_mf_name(tokens, true); maybe_name.has_value()) { @@ -1012,6 +1013,7 @@ Optional<MediaFeature> Parser::parse_media_feature(TokenStream<ComponentValue>& if (auto maybe_value = parse_media_feature_value(maybe_name->id, tokens); maybe_value.has_value()) { tokens.skip_whitespace(); if (!tokens.has_next_token()) { + transaction.commit(); switch (maybe_name->type) { case MediaFeatureName::Type::Normal: return MediaFeature::plain(maybe_name->id, maybe_value.release_value()); @@ -1025,8 +1027,6 @@ Optional<MediaFeature> Parser::parse_media_feature(TokenStream<ComponentValue>& } } } - - tokens.rewind_to_position(position); return {}; }; @@ -1035,33 +1035,38 @@ Optional<MediaFeature> Parser::parse_media_feature(TokenStream<ComponentValue>& // <mf-eq> = '=' // <mf-comparison> = <mf-lt> | <mf-gt> | <mf-eq>` auto parse_comparison = [](auto& tokens) -> Optional<MediaFeature::Comparison> { - auto position = tokens.position(); + auto transaction = tokens.begin_transaction(); tokens.skip_whitespace(); auto& first = tokens.next_token(); if (first.is(Token::Type::Delim)) { auto first_delim = first.token().delim(); - if (first_delim == '=') + if (first_delim == '=') { + transaction.commit(); return MediaFeature::Comparison::Equal; + } if (first_delim == '<') { auto& second = tokens.peek_token(); if (second.is(Token::Type::Delim) && second.token().delim() == '=') { tokens.next_token(); + transaction.commit(); return MediaFeature::Comparison::LessThanOrEqual; } + transaction.commit(); return MediaFeature::Comparison::LessThan; } if (first_delim == '>') { auto& second = tokens.peek_token(); if (second.is(Token::Type::Delim) && second.token().delim() == '=') { tokens.next_token(); + transaction.commit(); return MediaFeature::Comparison::GreaterThanOrEqual; } + transaction.commit(); return MediaFeature::Comparison::GreaterThan; } } - tokens.rewind_to_position(position); return {}; }; @@ -1100,7 +1105,7 @@ Optional<MediaFeature> Parser::parse_media_feature(TokenStream<ComponentValue>& // | <mf-value> <mf-lt> <mf-name> <mf-lt> <mf-value> // | <mf-value> <mf-gt> <mf-name> <mf-gt> <mf-value>` auto parse_mf_range = [&](auto& tokens) -> Optional<MediaFeature> { - auto position = tokens.position(); + auto transaction = tokens.begin_transaction(); tokens.skip_whitespace(); // `<mf-name> <mf-comparison> <mf-value>` @@ -1111,8 +1116,10 @@ Optional<MediaFeature> Parser::parse_media_feature(TokenStream<ComponentValue>& tokens.skip_whitespace(); if (auto maybe_value = parse_media_feature_value(maybe_name->id, tokens); maybe_value.has_value()) { tokens.skip_whitespace(); - if (!tokens.has_next_token() && !maybe_value->is_ident()) + if (!tokens.has_next_token() && !maybe_value->is_ident()) { + transaction.commit(); return MediaFeature::half_range(maybe_value.release_value(), flip(maybe_comparison.release_value()), maybe_name->id); + } } } } @@ -1125,18 +1132,20 @@ Optional<MediaFeature> Parser::parse_media_feature(TokenStream<ComponentValue>& // treat the next non-whitespace token as the <mf-name>, which should be correct as long as they don't add a value // type that can include a comparison in it. :^) Optional<MediaFeatureName> maybe_name; - while (tokens.has_next_token() && !maybe_name.has_value()) { - if (auto maybe_comparison = parse_comparison(tokens); maybe_comparison.has_value()) { - // We found a comparison, so the next non-whitespace token should be the <mf-name> + { + // This transaction is never committed, we just use it to rewind automatically. + auto temp_transaction = tokens.begin_transaction(); + while (tokens.has_next_token() && !maybe_name.has_value()) { + if (auto maybe_comparison = parse_comparison(tokens); maybe_comparison.has_value()) { + // We found a comparison, so the next non-whitespace token should be the <mf-name> + tokens.skip_whitespace(); + maybe_name = parse_mf_name(tokens, false); + break; + } + tokens.next_token(); tokens.skip_whitespace(); - maybe_name = parse_mf_name(tokens, false); - break; } - tokens.next_token(); - tokens.skip_whitespace(); } - tokens.rewind_to_position(position); - tokens.skip_whitespace(); // Now, we can parse the range properly. if (maybe_name.has_value() && media_feature_type_is_range(maybe_name->id)) { @@ -1147,8 +1156,10 @@ Optional<MediaFeature> Parser::parse_media_feature(TokenStream<ComponentValue>& tokens.next_token(); // The <mf-name> which we already parsed above. tokens.skip_whitespace(); - if (!tokens.has_next_token()) + if (!tokens.has_next_token()) { + transaction.commit(); return MediaFeature::half_range(maybe_left_value.release_value(), maybe_left_comparison.release_value(), maybe_name->id); + } if (auto maybe_right_comparison = parse_comparison(tokens); maybe_right_comparison.has_value()) { tokens.skip_whitespace(); @@ -1165,6 +1176,7 @@ Optional<MediaFeature> Parser::parse_media_feature(TokenStream<ComponentValue>& && comparisons_match(left_comparison, right_comparison) && left_comparison != MediaFeature::Comparison::Equal && !maybe_left_value->is_ident() && !maybe_right_value->is_ident()) { + transaction.commit(); return MediaFeature::range(maybe_left_value.release_value(), left_comparison, maybe_name->id, right_comparison, maybe_right_value.release_value()); } } @@ -1173,7 +1185,6 @@ Optional<MediaFeature> Parser::parse_media_feature(TokenStream<ComponentValue>& } } - tokens.rewind_to_position(position); return {}; }; @@ -1186,27 +1197,24 @@ Optional<MediaFeature> Parser::parse_media_feature(TokenStream<ComponentValue>& if (auto maybe_mf_range = parse_mf_range(tokens); maybe_mf_range.has_value()) return maybe_mf_range.release_value(); - tokens.rewind_to_position(position); return {}; } Optional<MediaQuery::MediaType> Parser::parse_media_type(TokenStream<ComponentValue>& tokens) { - auto position = tokens.position(); + auto transaction = tokens.begin_transaction(); tokens.skip_whitespace(); auto& token = tokens.next_token(); - if (!token.is(Token::Type::Ident)) { - tokens.rewind_to_position(position); + if (!token.is(Token::Type::Ident)) return {}; - } auto ident = token.token().ident(); if (auto media_type = media_type_from_string(ident); media_type.has_value()) { + transaction.commit(); return media_type.release_value(); } - tokens.rewind_to_position(position); return {}; } @@ -1214,7 +1222,7 @@ Optional<MediaQuery::MediaType> Parser::parse_media_type(TokenStream<ComponentVa OwnPtr<MediaCondition> Parser::parse_media_in_parens(TokenStream<ComponentValue>& tokens) { // `<media-in-parens> = ( <media-condition> ) | ( <media-feature> ) | <general-enclosed>` - auto position = tokens.position(); + auto transaction = tokens.begin_transaction(); tokens.skip_whitespace(); // `( <media-condition> ) | ( <media-feature> )` @@ -1223,10 +1231,12 @@ OwnPtr<MediaCondition> Parser::parse_media_in_parens(TokenStream<ComponentValue> TokenStream inner_token_stream { first_token.block().values() }; if (auto maybe_media_condition = parse_media_condition(inner_token_stream, MediaCondition::AllowOr::Yes)) { tokens.next_token(); + transaction.commit(); return maybe_media_condition.release_nonnull(); } if (auto maybe_media_feature = parse_media_feature(inner_token_stream); maybe_media_feature.has_value()) { tokens.next_token(); + transaction.commit(); return MediaCondition::from_feature(maybe_media_feature.release_value()); } } @@ -1235,64 +1245,85 @@ OwnPtr<MediaCondition> Parser::parse_media_in_parens(TokenStream<ComponentValue> // FIXME: We should only be taking this branch if the grammar doesn't match the above options. // Currently we take it if the above fail to parse, which is different. // eg, `@media (min-width: 76yaks)` is valid grammar, but does not parse because `yaks` isn't a unit. - if (auto maybe_general_enclosed = parse_general_enclosed(tokens); maybe_general_enclosed.has_value()) + if (auto maybe_general_enclosed = parse_general_enclosed(tokens); maybe_general_enclosed.has_value()) { + transaction.commit(); return MediaCondition::from_general_enclosed(maybe_general_enclosed.release_value()); + } - tokens.rewind_to_position(position); return {}; } // `<mf-value>`, https://www.w3.org/TR/mediaqueries-4/#typedef-mf-value Optional<MediaFeatureValue> Parser::parse_media_feature_value(MediaFeatureID media_feature, TokenStream<ComponentValue>& tokens) { - auto position = tokens.position(); - tokens.skip_whitespace(); - auto& first = tokens.next_token(); - tokens.skip_whitespace(); - // Identifiers - if (first.is(Token::Type::Ident)) { - auto ident = value_id_from_string(first.token().ident()); - if (ident != ValueID::Invalid && media_feature_accepts_identifier(media_feature, ident)) + if (tokens.peek_token().is(Token::Type::Ident)) { + auto transaction = tokens.begin_transaction(); + tokens.skip_whitespace(); + auto ident = value_id_from_string(tokens.next_token().token().ident()); + if (ident != ValueID::Invalid && media_feature_accepts_identifier(media_feature, ident)) { + transaction.commit(); return MediaFeatureValue(ident); + } } // One branch for each member of the MediaFeatureValueType enum: // Boolean (<mq-boolean> in the spec: a 1 or 0) if (media_feature_accepts_type(media_feature, MediaFeatureValueType::Boolean)) { + auto transaction = tokens.begin_transaction(); + tokens.skip_whitespace(); + auto& first = tokens.next_token(); if (first.is(Token::Type::Number) && first.token().number().is_integer() - && (first.token().number_value() == 0 || first.token().number_value() == 1)) + && (first.token().number_value() == 0 || first.token().number_value() == 1)) { + transaction.commit(); return MediaFeatureValue(first.token().number_value()); + } } // Integer if (media_feature_accepts_type(media_feature, MediaFeatureValueType::Integer)) { - if (first.is(Token::Type::Number) && first.token().number().is_integer()) + auto transaction = tokens.begin_transaction(); + tokens.skip_whitespace(); + auto& first = tokens.next_token(); + if (first.is(Token::Type::Number) && first.token().number().is_integer()) { + transaction.commit(); return MediaFeatureValue(first.token().number_value()); + } } // Length if (media_feature_accepts_type(media_feature, MediaFeatureValueType::Length)) { - if (auto length = parse_length(first); length.has_value()) + auto transaction = tokens.begin_transaction(); + tokens.skip_whitespace(); + auto& first = tokens.next_token(); + if (auto length = parse_length(first); length.has_value()) { + transaction.commit(); return MediaFeatureValue(length.release_value()); - } - - // Resolution - if (media_feature_accepts_type(media_feature, MediaFeatureValueType::Resolution)) { - if (auto resolution = parse_dimension(first); resolution.has_value() && resolution->is_resolution()) - return MediaFeatureValue(resolution->resolution()); + } } // Ratio - // Done last because it uses multiple tokens. - tokens.rewind_to_position(position); if (media_feature_accepts_type(media_feature, MediaFeatureValueType::Ratio)) { - if (auto ratio = parse_ratio(tokens); ratio.has_value()) + auto transaction = tokens.begin_transaction(); + tokens.skip_whitespace(); + if (auto ratio = parse_ratio(tokens); ratio.has_value()) { + transaction.commit(); return MediaFeatureValue(ratio.release_value()); + } + } + + // Resolution + if (media_feature_accepts_type(media_feature, MediaFeatureValueType::Resolution)) { + auto transaction = tokens.begin_transaction(); + tokens.skip_whitespace(); + auto& first = tokens.next_token(); + if (auto resolution = parse_dimension(first); resolution.has_value() && resolution->is_resolution()) { + transaction.commit(); + return MediaFeatureValue(resolution->resolution()); + } } - tokens.rewind_to_position(position); return {}; } |