LibWeb: Make serializing media-queries infallible

Userland/Libraries/LibWeb/CSS/MediaList.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2021, Sam Atkins <atkinssj@serenityos.org>
+ * Copyright (c) 2021-2023, Sam Atkins <atkinssj@serenityos.org>
  * Copyright (c) 2022-2023, Andreas Kling <kling@serenityos.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
@@ -33,7 +33,7 @@ void MediaList::initialize(JS::Realm& realm)
 // https://www.w3.org/TR/cssom-1/#dom-medialist-mediatext
 DeprecatedString MediaList::media_text() const
 {
-    return serialize_a_media_query_list(m_media).release_value_but_fixme_should_propagate_errors().to_deprecated_string();
+    return serialize_a_media_query_list(m_media).to_deprecated_string();
 }
 
 // https://www.w3.org/TR/cssom-1/#dom-medialist-mediatext
@@ -56,7 +56,7 @@ DeprecatedString MediaList::item(u32 index) const
     if (!is_supported_property_index(index))
         return {};
 
-    return m_media[index]->to_string().release_value_but_fixme_should_propagate_errors().to_deprecated_string();
+    return m_media[index]->to_string().to_deprecated_string();
 }
 
 // https://www.w3.org/TR/cssom-1/#dom-medialist-appendmedium
@@ -70,9 +70,9 @@ void MediaList::append_medium(DeprecatedString medium)
         return;
 
     // 3. If comparing m with any of the media queries in the collection of media queries returns true, then return.
-    auto serialized = m->to_string().release_value_but_fixme_should_propagate_errors();
+    auto serialized = m->to_string();
     for (auto& existing_medium : m_media) {
-        if (existing_medium->to_string().release_value_but_fixme_should_propagate_errors() == serialized)
+        if (existing_medium->to_string() == serialized)
             return;
     }
 
@@ -87,7 +87,7 @@ void MediaList::delete_medium(DeprecatedString medium)
     if (!m)
         return;
     m_media.remove_all_matching([&](auto& existing) -> bool {
-        return m->to_string().release_value_but_fixme_should_propagate_errors() == existing->to_string().release_value_but_fixme_should_propagate_errors();
+        return m->to_string() == existing->to_string();
     });
     // FIXME: If nothing was removed, then throw a NotFoundError exception.
 }
@@ -117,7 +117,7 @@ WebIDL::ExceptionOr<JS::Value> MediaList::item_value(size_t index) const
 {
     if (index >= m_media.size())
         return JS::js_undefined();
-    return JS::PrimitiveString::create(vm(), m_media[index]->to_string().release_value_but_fixme_should_propagate_errors().to_deprecated_string());
+    return JS::PrimitiveString::create(vm(), m_media[index]->to_string().to_deprecated_string());
 }
 
 }

Userland/Libraries/LibWeb/CSS/MediaQuery.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2021, Sam Atkins <atkinssj@serenityos.org>
+ * Copyright (c) 2021-2023, Sam Atkins <atkinssj@serenityos.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
@@ -21,7 +21,7 @@ NonnullRefPtr<MediaQuery> MediaQuery::create_not_all()
     return adopt_ref(*media_query);
 }
 
-ErrorOr<String> MediaFeatureValue::to_string() const
+String MediaFeatureValue::to_string() const
 {
     return m_value.visit(
         [](ValueID const& ident) { return MUST(String::from_utf8(string_from_value_id(ident))); },
@@ -41,7 +41,7 @@ bool MediaFeatureValue::is_same_type(MediaFeatureValue const& other) const
         [&](float) { return other.is_number(); });
 }
 
-ErrorOr<String> MediaFeature::to_string() const
+String MediaFeature::to_string() const
 {
     auto comparison_string = [](Comparison comparison) -> StringView {
         switch (comparison) {
@@ -61,18 +61,18 @@ ErrorOr<String> MediaFeature::to_string() const
 
     switch (m_type) {
     case Type::IsTrue:
-        return String::from_utf8(string_from_media_feature_id(m_id));
+        return MUST(String::from_utf8(string_from_media_feature_id(m_id)));
     case Type::ExactValue:
-        return String::formatted("{}:{}", string_from_media_feature_id(m_id), TRY(m_value->to_string()));
+        return MUST(String::formatted("{}:{}", string_from_media_feature_id(m_id), m_value->to_string()));
     case Type::MinValue:
-        return String::formatted("min-{}:{}", string_from_media_feature_id(m_id), TRY(m_value->to_string()));
+        return MUST(String::formatted("min-{}:{}", string_from_media_feature_id(m_id), m_value->to_string()));
     case Type::MaxValue:
-        return String::formatted("max-{}:{}", string_from_media_feature_id(m_id), TRY(m_value->to_string()));
+        return MUST(String::formatted("max-{}:{}", string_from_media_feature_id(m_id), m_value->to_string()));
     case Type::Range:
         if (!m_range->right_comparison.has_value())
-            return String::formatted("{} {} {}", TRY(m_range->left_value.to_string()), comparison_string(m_range->left_comparison), string_from_media_feature_id(m_id));
+            return MUST(String::formatted("{} {} {}", m_range->left_value.to_string(), comparison_string(m_range->left_comparison), string_from_media_feature_id(m_id)));
 
-        return String::formatted("{} {} {} {} {}", TRY(m_range->left_value.to_string()), comparison_string(m_range->left_comparison), string_from_media_feature_id(m_id), comparison_string(*m_range->right_comparison), TRY(m_range->right_value->to_string()));
+        return MUST(String::formatted("{} {} {} {} {}", m_range->left_value.to_string(), comparison_string(m_range->left_comparison), string_from_media_feature_id(m_id), comparison_string(*m_range->right_comparison), m_range->right_value->to_string()));
     }
 
     VERIFY_NOT_REACHED();
@@ -276,17 +276,17 @@ NonnullOwnPtr<MediaCondition> MediaCondition::from_or_list(Vector<NonnullOwnPtr<
     return adopt_own(*result);
 }
 
-ErrorOr<String> MediaCondition::to_string() const
+String MediaCondition::to_string() const
 {
     StringBuilder builder;
     builder.append('(');
     switch (type) {
     case Type::Single:
-        builder.append(TRY(feature->to_string()));
+        builder.append(feature->to_string());
         break;
     case Type::Not:
         builder.append("not "sv);
-        builder.append(TRY(conditions.first()->to_string()));
+        builder.append(conditions.first()->to_string());
         break;
     case Type::And:
         builder.join(" and "sv, conditions);
@@ -299,7 +299,7 @@ ErrorOr<String> MediaCondition::to_string() const
         break;
     }
     builder.append(')');
-    return builder.to_string();
+    return MUST(builder.to_string());
 }
 
 MatchResult MediaCondition::evaluate(HTML::Window const& window) const
@@ -319,7 +319,7 @@ MatchResult MediaCondition::evaluate(HTML::Window const& window) const
     VERIFY_NOT_REACHED();
 }
 
-ErrorOr<String> MediaQuery::to_string() const
+String MediaQuery::to_string() const
 {
     StringBuilder builder;
 
@@ -333,10 +333,10 @@ ErrorOr<String> MediaQuery::to_string() const
     }
 
     if (m_media_condition) {
-        builder.append(TRY(m_media_condition->to_string()));
+        builder.append(m_media_condition->to_string());
     }
 
-    return builder.to_string();
+    return MUST(builder.to_string());
 }
 
 bool MediaQuery::evaluate(HTML::Window const& window)
@@ -380,7 +380,7 @@ bool MediaQuery::evaluate(HTML::Window const& window)
 }
 
 // https://www.w3.org/TR/cssom-1/#serialize-a-media-query-list
-ErrorOr<String> serialize_a_media_query_list(Vector<NonnullRefPtr<MediaQuery>> const& media_queries)
+String serialize_a_media_query_list(Vector<NonnullRefPtr<MediaQuery>> const& media_queries)
 {
     // 1. If the media query list is empty, then return the empty string.
     if (media_queries.is_empty())
@@ -388,7 +388,7 @@ ErrorOr<String> serialize_a_media_query_list(Vector<NonnullRefPtr<MediaQuery>> c
 
     // 2. Serialize each media query in the list of media queries, in the same order as they
     // appear in the media query list, and then serialize the list.
-    return String::join(", "sv, media_queries);
+    return MUST(String::join(", "sv, media_queries));
 }
 
 bool is_media_feature_name(StringView name)

Userland/Libraries/LibWeb/CSS/MediaQuery.h

@@ -46,7 +46,7 @@ public:
     {
     }
 
-    ErrorOr<String> to_string() const;
+    String to_string() const;
 
     bool is_ident() const { return m_value.has<ValueID>(); }
     bool is_length() const { return m_value.has<Length>(); }
@@ -145,7 +145,7 @@ public:
     }
 
     bool evaluate(HTML::Window const&) const;
-    ErrorOr<String> to_string() const;
+    String to_string() const;
 
 private:
     enum class Type {
@@ -201,7 +201,7 @@ struct MediaCondition {
     static NonnullOwnPtr<MediaCondition> from_or_list(Vector<NonnullOwnPtr<MediaCondition>>&&);
 
     MatchResult evaluate(HTML::Window const&) const;
-    ErrorOr<String> to_string() const;
+    String to_string() const;
 
 private:
     MediaCondition() = default;
@@ -240,7 +240,7 @@ public:
 
     bool matches() const { return m_matches; }
     bool evaluate(HTML::Window const&);
-    ErrorOr<String> to_string() const;
+    String to_string() const;
 
 private:
     MediaQuery() = default;
@@ -254,7 +254,7 @@ private:
     bool m_matches { false };
 };
 
-ErrorOr<String> serialize_a_media_query_list(Vector<NonnullRefPtr<MediaQuery>> const&);
+String serialize_a_media_query_list(Vector<NonnullRefPtr<MediaQuery>> const&);
 
 bool is_media_feature_name(StringView name);
 
@@ -269,7 +269,7 @@ template<>
 struct Formatter<Web::CSS::MediaFeature> : Formatter<StringView> {
     ErrorOr<void> format(FormatBuilder& builder, Web::CSS::MediaFeature const& media_feature)
     {
-        return Formatter<StringView>::format(builder, TRY(media_feature.to_string()));
+        return Formatter<StringView>::format(builder, media_feature.to_string());
     }
 };
 
@@ -277,7 +277,7 @@ template<>
 struct Formatter<Web::CSS::MediaCondition> : Formatter<StringView> {
     ErrorOr<void> format(FormatBuilder& builder, Web::CSS::MediaCondition const& media_condition)
     {
-        return Formatter<StringView>::format(builder, TRY(media_condition.to_string()));
+        return Formatter<StringView>::format(builder, media_condition.to_string());
     }
 };
 
@@ -285,7 +285,7 @@ template<>
 struct Formatter<Web::CSS::MediaQuery> : Formatter<StringView> {
     ErrorOr<void> format(FormatBuilder& builder, Web::CSS::MediaQuery const& media_query)
     {
-        return Formatter<StringView>::format(builder, TRY(media_query.to_string()));
+        return Formatter<StringView>::format(builder, media_query.to_string());
     }
 };
 

Userland/Libraries/LibWeb/CSS/MediaQueryList.cpp

@@ -43,7 +43,7 @@ void MediaQueryList::visit_edges(Cell::Visitor& visitor)
 // https://drafts.csswg.org/cssom-view/#dom-mediaquerylist-media
 DeprecatedString MediaQueryList::media() const
 {
-    return serialize_a_media_query_list(m_media).release_value_but_fixme_should_propagate_errors().to_deprecated_string();
+    return serialize_a_media_query_list(m_media).to_deprecated_string();
 }
 
 // https://drafts.csswg.org/cssom-view/#dom-mediaquerylist-matches