LibJS: Make PrimitiveString::utf8_string() infallible

Work towards #20449.

Userland/Libraries/LibJS/Console.cpp

@@ -59,7 +59,7 @@ ThrowCompletionOr<Value> Console::assert_()
         // 3. Otherwise:
         else {
             // 1. Let concat be the concatenation of message, U+003A (:), U+0020 SPACE, and first.
-            auto concat = TRY_OR_THROW_OOM(vm, String::formatted("{}: {}", TRY(message->utf8_string()), MUST(first.to_string(vm))));
+            auto concat = TRY_OR_THROW_OOM(vm, String::formatted("{}: {}", message->utf8_string(), MUST(first.to_string(vm))));
             // 2. Set data[0] to concat.
             data[0] = PrimitiveString::create(vm, move(concat));
         }

Userland/Libraries/LibJS/Runtime/Intl/AbstractOperations.cpp

@@ -384,7 +384,7 @@ ThrowCompletionOr<LocaleResult> resolve_locale(VM& vm, Vector<String> const& req
     MatcherResult matcher_result;
 
     // 2. If matcher is "lookup", then
-    if (matcher.is_string() && (TRY(matcher.as_string().utf8_string_view()) == "lookup"sv)) {
+    if (matcher.is_string() && (matcher.as_string().utf8_string_view()) == "lookup"sv) {
         // a. Let r be ! LookupMatcher(availableLocales, requestedLocales).
         matcher_result = MUST_OR_THROW_OOM(lookup_matcher(vm, requested_locales));
     }
@@ -576,7 +576,7 @@ ThrowCompletionOr<Array*> supported_locales(VM& vm, Vector<String> const& reques
     Vector<String> supported_locales;
 
     // 3. If matcher is "best fit", then
-    if (TRY(matcher.as_string().utf8_string_view()) == "best fit"sv) {
+    if (matcher.as_string().utf8_string_view() == "best fit"sv) {
         // a. Let supportedLocales be BestFitSupportedLocales(availableLocales, requestedLocales).
         supported_locales = TRY(best_fit_supported_locales(vm, requested_locales));
     }

Userland/Libraries/LibJS/Runtime/Intl/CollatorConstructor.cpp

@@ -27,7 +27,7 @@ static ThrowCompletionOr<Collator*> initialize_collator(VM& vm, Collator& collat
     auto usage = TRY(get_option(vm, *options, vm.names.usage, OptionType::String, { "sort"sv, "search"sv }, "sort"sv));
 
     // 4. Set collator.[[Usage]] to usage.
-    collator.set_usage(TRY(usage.as_string().utf8_string_view()));
+    collator.set_usage(usage.as_string().utf8_string_view());
 
     // 5. If usage is "sort", then
     //     a. Let localeData be %Collator%.[[SortLocaleData]].
@@ -49,11 +49,11 @@ static ThrowCompletionOr<Collator*> initialize_collator(VM& vm, Collator& collat
     // 11. If collation is not undefined, then
     if (!collation.is_undefined()) {
         // a. If collation does not match the Unicode Locale Identifier type nonterminal, throw a RangeError exception.
-        if (!::Locale::is_type_identifier(TRY(collation.as_string().utf8_string_view())))
+        if (!::Locale::is_type_identifier(collation.as_string().utf8_string_view()))
             return vm.throw_completion<RangeError>(ErrorType::OptionIsNotValidValue, collation, "collation"sv);
 
         // 12. Set opt.[[co]] to collation.
-        opt.co = TRY(collation.as_string().utf8_string());
+        opt.co = collation.as_string().utf8_string();
     }
 
     // 13. Let numeric be ? GetOption(options, "numeric", boolean, empty, undefined).
@@ -69,7 +69,7 @@ static ThrowCompletionOr<Collator*> initialize_collator(VM& vm, Collator& collat
     // 17. Set opt.[[kf]] to caseFirst.
     auto case_first = TRY(get_option(vm, *options, vm.names.caseFirst, OptionType::String, { "upper"sv, "lower"sv, "false"sv }, Empty {}));
     if (!case_first.is_undefined())
-        opt.kf = TRY(case_first.as_string().utf8_string());
+        opt.kf = case_first.as_string().utf8_string();
 
     // 18. Let relevantExtensionKeys be %Collator%.[[RelevantExtensionKeys]].
     auto relevant_extension_keys = Collator::relevant_extension_keys();
@@ -117,7 +117,7 @@ static ThrowCompletionOr<Collator*> initialize_collator(VM& vm, Collator& collat
     }
 
     // 28. Set collator.[[Sensitivity]] to sensitivity.
-    collator.set_sensitivity(TRY(sensitivity.as_string().utf8_string_view()));
+    collator.set_sensitivity(sensitivity.as_string().utf8_string_view());
 
     // 29. Let ignorePunctuation be ? GetOption(options, "ignorePunctuation", boolean, empty, false).
     auto ignore_punctuation = TRY(get_option(vm, *options, vm.names.ignorePunctuation, OptionType::Boolean, {}, false));

Userland/Libraries/LibJS/Runtime/Intl/DateTimeFormatConstructor.cpp

@@ -106,11 +106,11 @@ ThrowCompletionOr<NonnullGCPtr<DateTimeFormat>> create_date_time_format(VM& vm,
     // 8. If calendar is not undefined, then
     if (!calendar.is_undefined()) {
         // a. If calendar cannot be matched by the type Unicode locale nonterminal, throw a RangeError exception.
-        if (!::Locale::is_type_identifier(TRY(calendar.as_string().utf8_string_view())))
+        if (!::Locale::is_type_identifier(calendar.as_string().utf8_string_view()))
             return vm.throw_completion<RangeError>(ErrorType::OptionIsNotValidValue, calendar, "calendar"sv);
 
         // 9. Set opt.[[ca]] to calendar.
-        opt.ca = TRY(calendar.as_string().utf8_string());
+        opt.ca = calendar.as_string().utf8_string();
     }
 
     // 10. Let numberingSystem be ? GetOption(options, "numberingSystem", string, empty, undefined).
@@ -119,11 +119,11 @@ ThrowCompletionOr<NonnullGCPtr<DateTimeFormat>> create_date_time_format(VM& vm,
     // 11. If numberingSystem is not undefined, then
     if (!numbering_system.is_undefined()) {
         // a. If numberingSystem cannot be matched by the type Unicode locale nonterminal, throw a RangeError exception.
-        if (!::Locale::is_type_identifier(TRY(numbering_system.as_string().utf8_string_view())))
+        if (!::Locale::is_type_identifier(numbering_system.as_string().utf8_string_view()))
             return vm.throw_completion<RangeError>(ErrorType::OptionIsNotValidValue, numbering_system, "numberingSystem"sv);
 
         // 12. Set opt.[[nu]] to numberingSystem.
-        opt.nu = TRY(numbering_system.as_string().utf8_string());
+        opt.nu = numbering_system.as_string().utf8_string();
     }
 
     // 13. Let hour12 be ? GetOption(options, "hour12", boolean, empty, undefined).
@@ -140,7 +140,7 @@ ThrowCompletionOr<NonnullGCPtr<DateTimeFormat>> create_date_time_format(VM& vm,
 
     // 16. Set opt.[[hc]] to hourCycle.
     if (!hour_cycle.is_nullish())
-        opt.hc = TRY(hour_cycle.as_string().utf8_string());
+        opt.hc = hour_cycle.as_string().utf8_string();
 
     // 17. Let localeData be %DateTimeFormat%.[[LocaleData]].
     // 18. Let r be ResolveLocale(%DateTimeFormat%.[[AvailableLocales]], requestedLocales, opt, %DateTimeFormat%.[[RelevantExtensionKeys]], localeData).
@@ -275,7 +275,7 @@ ThrowCompletionOr<NonnullGCPtr<DateTimeFormat>> create_date_time_format(VM& vm,
 
             // d. Set formatOptions.[[<prop>]] to value.
             if (!value.is_undefined()) {
-                option = ::Locale::calendar_pattern_style_from_string(TRY(value.as_string().utf8_string_view()));
+                option = ::Locale::calendar_pattern_style_from_string(value.as_string().utf8_string_view());
 
                 // e. If value is not undefined, then
                 //     i. Set hasExplicitFormatComponents to true.
@@ -294,14 +294,14 @@ ThrowCompletionOr<NonnullGCPtr<DateTimeFormat>> create_date_time_format(VM& vm,
 
     // 40. Set dateTimeFormat.[[DateStyle]] to dateStyle.
     if (!date_style.is_undefined())
-        date_time_format->set_date_style(TRY(date_style.as_string().utf8_string_view()));
+        date_time_format->set_date_style(date_style.as_string().utf8_string_view());
 
     // 41. Let timeStyle be ? GetOption(options, "timeStyle", string, « "full", "long", "medium", "short" », undefined).
     auto time_style = TRY(get_option(vm, *options, vm.names.timeStyle, OptionType::String, AK::Array { "full"sv, "long"sv, "medium"sv, "short"sv }, Empty {}));
 
     // 42. Set dateTimeFormat.[[TimeStyle]] to timeStyle.
     if (!time_style.is_undefined())
-        date_time_format->set_time_style(TRY(time_style.as_string().utf8_string_view()));
+        date_time_format->set_time_style(time_style.as_string().utf8_string_view());
 
     Optional<::Locale::CalendarPattern> best_format {};
 
@@ -397,7 +397,7 @@ ThrowCompletionOr<NonnullGCPtr<DateTimeFormat>> create_date_time_format(VM& vm,
         auto formats = TRY_OR_THROW_OOM(vm, ::Locale::get_calendar_available_formats(data_locale, date_time_format->calendar()));
 
         // g. If matcher is "basic", then
-        if (TRY(matcher.as_string().utf8_string_view()) == "basic"sv) {
+        if (matcher.as_string().utf8_string_view() == "basic"sv) {
             // i. Let bestFormat be BasicFormatMatcher(formatOptions, formats).
             best_format = basic_format_matcher(format_options, move(formats));
         }

Userland/Libraries/LibJS/Runtime/Intl/DisplayNamesConstructor.cpp

@@ -82,7 +82,7 @@ ThrowCompletionOr<NonnullGCPtr<Object>> DisplayNamesConstructor::construct(Funct
     auto style = TRY(get_option(vm, *options, vm.names.style, OptionType::String, { "narrow"sv, "short"sv, "long"sv }, "long"sv));
 
     // 12. Set displayNames.[[Style]] to style.
-    display_names->set_style(TRY(style.as_string().utf8_string_view()));
+    display_names->set_style(style.as_string().utf8_string_view());
 
     // 13. Let type be ? GetOption(options, "type", string, « "language", "region", "script", "currency", "calendar", "dateTimeField" », undefined).
     auto type = TRY(get_option(vm, *options, vm.names.type, OptionType::String, { "language"sv, "region"sv, "script"sv, "currency"sv, "calendar"sv, "dateTimeField"sv }, Empty {}));
@@ -92,13 +92,13 @@ ThrowCompletionOr<NonnullGCPtr<Object>> DisplayNamesConstructor::construct(Funct
         return vm.throw_completion<TypeError>(ErrorType::IsUndefined, "options.type"sv);
 
     // 15. Set displayNames.[[Type]] to type.
-    display_names->set_type(TRY(type.as_string().utf8_string_view()));
+    display_names->set_type(type.as_string().utf8_string_view());
 
     // 16. Let fallback be ? GetOption(options, "fallback", string, « "code", "none" », "code").
     auto fallback = TRY(get_option(vm, *options, vm.names.fallback, OptionType::String, { "code"sv, "none"sv }, "code"sv));
 
     // 17. Set displayNames.[[Fallback]] to fallback.
-    display_names->set_fallback(TRY(fallback.as_string().utf8_string_view()));
+    display_names->set_fallback(fallback.as_string().utf8_string_view());
 
     // 18. Set displayNames.[[Locale]] to r.[[locale]].
     display_names->set_locale(move(result.locale));
@@ -119,7 +119,7 @@ ThrowCompletionOr<NonnullGCPtr<Object>> DisplayNamesConstructor::construct(Funct
     // 26. If type is "language", then
     if (display_names->type() == DisplayNames::Type::Language) {
         // a. Set displayNames.[[LanguageDisplay]] to languageDisplay.
-        display_names->set_language_display(TRY(language_display.as_string().utf8_string_view()));
+        display_names->set_language_display(language_display.as_string().utf8_string_view());
 
         // b. Let typeFields be typeFields.[[<languageDisplay>]].
         // c. Assert: typeFields is a Record (see 12.4.3).

Userland/Libraries/LibJS/Runtime/Intl/DisplayNamesPrototype.cpp

@@ -46,8 +46,8 @@ JS_DEFINE_NATIVE_FUNCTION(DisplayNamesPrototype::of)
     code = PrimitiveString::create(vm, TRY(code.to_string(vm)));
 
     // 4. Let code be ? CanonicalCodeForDisplayNames(displayNames.[[Type]], code).
-    code = TRY(canonical_code_for_display_names(vm, display_names->type(), TRY(code.as_string().utf8_string_view())));
-    auto code_string = TRY(code.as_string().utf8_string_view());
+    code = TRY(canonical_code_for_display_names(vm, display_names->type(), code.as_string().utf8_string_view()));
+    auto code_string = code.as_string().utf8_string_view();
 
     // 5. Let fields be displayNames.[[Fields]].
     // 6. If fields has a field [[<code>]], return fields.[[<code>]].

Userland/Libraries/LibJS/Runtime/Intl/DurationFormat.cpp

@@ -309,7 +309,7 @@ ThrowCompletionOr<DurationUnitOptions> get_duration_unit_options(VM& vm, String
             }
         }
     } else {
-        style = TRY(style_value.as_string().utf8_string_view());
+        style = style_value.as_string().utf8_string_view();
     }
 
     // 4. Let displayField be the string-concatenation of unit and "Display".
@@ -333,7 +333,7 @@ ThrowCompletionOr<DurationUnitOptions> get_duration_unit_options(VM& vm, String
     }
 
     // 7. Return the Record { [[Style]]: style, [[Display]]: display }.
-    return DurationUnitOptions { .style = TRY_OR_THROW_OOM(vm, String::from_utf8(style)), .display = TRY(display.as_string().utf8_string()) };
+    return DurationUnitOptions { .style = TRY_OR_THROW_OOM(vm, String::from_utf8(style)), .display = display.as_string().utf8_string() };
 }
 
 // 1.1.7 PartitionDurationFormatPattern ( durationFormat, duration ), https://tc39.es/proposal-intl-duration-format/#sec-partitiondurationformatpattern

Userland/Libraries/LibJS/Runtime/Intl/DurationFormatConstructor.cpp

@@ -67,14 +67,14 @@ ThrowCompletionOr<NonnullGCPtr<Object>> DurationFormatConstructor::construct(Fun
     // 7. If numberingSystem is not undefined, then
     if (!numbering_system.is_undefined()) {
         // a. If numberingSystem does not match the Unicode Locale Identifier type nonterminal, throw a RangeError exception.
-        if (!::Locale::is_type_identifier(TRY(numbering_system.as_string().utf8_string_view())))
+        if (!::Locale::is_type_identifier(numbering_system.as_string().utf8_string_view()))
             return vm.throw_completion<RangeError>(ErrorType::OptionIsNotValidValue, numbering_system, "numberingSystem"sv);
     }
 
     // 8. Let opt be the Record { [[localeMatcher]]: matcher, [[nu]]: numberingSystem }.
     LocaleOptions opt {};
     opt.locale_matcher = matcher;
-    opt.nu = numbering_system.is_undefined() ? Optional<String>() : TRY(numbering_system.as_string().utf8_string());
+    opt.nu = numbering_system.is_undefined() ? Optional<String>() : numbering_system.as_string().utf8_string();
 
     // 9. Let r be ResolveLocale(%DurationFormat%.[[AvailableLocales]], requestedLocales, opt, %DurationFormat%.[[RelevantExtensionKeys]], %DurationFormat%.[[LocaleData]]).
     auto result = MUST_OR_THROW_OOM(resolve_locale(vm, requested_locales, opt, DurationFormat::relevant_extension_keys()));
@@ -93,7 +93,7 @@ ThrowCompletionOr<NonnullGCPtr<Object>> DurationFormatConstructor::construct(Fun
     auto style = TRY(get_option(vm, *options, vm.names.style, OptionType::String, { "long"sv, "short"sv, "narrow"sv, "digital"sv }, "short"sv));
 
     // 14. Set durationFormat.[[Style]] to style.
-    duration_format->set_style(TRY(style.as_string().utf8_string_view()));
+    duration_format->set_style(style.as_string().utf8_string_view());
 
     // 15. Set durationFormat.[[DataLocale]] to r.[[dataLocale]].
     duration_format->set_data_locale(move(result.data_locale));
@@ -119,7 +119,7 @@ ThrowCompletionOr<NonnullGCPtr<Object>> DurationFormatConstructor::construct(Fun
         auto digital_base = duration_instances_component.digital_default;
 
         // f. Let unitOptions be ? GetDurationUnitOptions(unit, options, style, valueList, digitalBase, prevStyle).
-        auto unit_options = TRY(get_duration_unit_options(vm, unit, *options, TRY(style.as_string().utf8_string_view()), value_list, digital_base, previous_style));
+        auto unit_options = TRY(get_duration_unit_options(vm, unit, *options, style.as_string().utf8_string_view(), value_list, digital_base, previous_style));
 
         // g. Set the value of the styleSlot slot of durationFormat to unitOptions.[[Style]].
         (duration_format->*style_slot)(unit_options.style);

Userland/Libraries/LibJS/Runtime/Intl/ListFormat.cpp

@@ -276,7 +276,7 @@ ThrowCompletionOr<Vector<String>> string_list_from_iterable(VM& vm, Value iterab
             }
 
             // iii. Append nextValue to the end of the List list.
-            TRY_OR_THROW_OOM(vm, list.try_append(TRY(next_value.as_string().utf8_string())));
+            TRY_OR_THROW_OOM(vm, list.try_append(next_value.as_string().utf8_string()));
         }
     } while (next != nullptr);
 

Userland/Libraries/LibJS/Runtime/Intl/ListFormatConstructor.cpp

@@ -80,13 +80,13 @@ ThrowCompletionOr<NonnullGCPtr<Object>> ListFormatConstructor::construct(Functio
     auto type = TRY(get_option(vm, *options, vm.names.type, OptionType::String, { "conjunction"sv, "disjunction"sv, "unit"sv }, "conjunction"sv));
 
     // 12. Set listFormat.[[Type]] to type.
-    list_format->set_type(TRY(type.as_string().utf8_string_view()));
+    list_format->set_type(type.as_string().utf8_string_view());
 
     // 13. Let style be ? GetOption(options, "style", string, « "long", "short", "narrow" », "long").
     auto style = TRY(get_option(vm, *options, vm.names.style, OptionType::String, { "long"sv, "short"sv, "narrow"sv }, "long"sv));
 
     // 14. Set listFormat.[[Style]] to style.
-    list_format->set_style(TRY(style.as_string().utf8_string_view()));
+    list_format->set_style(style.as_string().utf8_string_view());
 
     // Note: The remaining steps are skipped in favor of deferring to LibUnicode.
 

Userland/Libraries/LibJS/Runtime/Intl/LocaleConstructor.cpp

@@ -33,10 +33,10 @@ static ThrowCompletionOr<Optional<String>> get_string_option(VM& vm, Object cons
     if (option.is_undefined())
         return OptionalNone {};
 
-    if (validator && !validator(TRY(option.as_string().utf8_string_view())))
+    if (validator && !validator(option.as_string().utf8_string_view()))
         return vm.throw_completion<RangeError>(ErrorType::OptionIsNotValidValue, option, property);
 
-    return TRY(option.as_string().utf8_string());
+    return option.as_string().utf8_string();
 }
 
 // 14.1.2 ApplyOptionsToTag ( tag, options ), https://tc39.es/ecma402/#sec-apply-options-to-tag

Userland/Libraries/LibJS/Runtime/Intl/NumberFormat.cpp

@@ -1669,7 +1669,7 @@ ThrowCompletionOr<MathematicalValue> to_intl_mathematical_value(VM& vm, Value va
 
     // 3. If Type(primValue) is String,
     // a.     Let str be primValue.
-    auto string = TRY(primitive_value.as_string().utf8_string());
+    auto string = primitive_value.as_string().utf8_string();
 
     // Step 4 handled separately by the FIXME above.
 

Userland/Libraries/LibJS/Runtime/Intl/NumberFormatConstructor.cpp

@@ -102,11 +102,11 @@ ThrowCompletionOr<NumberFormat*> initialize_number_format(VM& vm, NumberFormat&
     // 7. If numberingSystem is not undefined, then
     if (!numbering_system.is_undefined()) {
         // a. If numberingSystem does not match the Unicode Locale Identifier type nonterminal, throw a RangeError exception.
-        if (!::Locale::is_type_identifier(TRY(numbering_system.as_string().utf8_string_view())))
+        if (!::Locale::is_type_identifier(numbering_system.as_string().utf8_string_view()))
             return vm.throw_completion<RangeError>(ErrorType::OptionIsNotValidValue, numbering_system, "numberingSystem"sv);
 
         // 8. Set opt.[[nu]] to numberingSystem.
-        opt.nu = TRY(numbering_system.as_string().utf8_string());
+        opt.nu = numbering_system.as_string().utf8_string();
     }
 
     // 9. Let localeData be %NumberFormat%.[[LocaleData]].
@@ -162,7 +162,7 @@ ThrowCompletionOr<NumberFormat*> initialize_number_format(VM& vm, NumberFormat&
     auto notation = TRY(get_option(vm, *options, vm.names.notation, OptionType::String, { "standard"sv, "scientific"sv, "engineering"sv, "compact"sv }, "standard"sv));
 
     // 19. Set numberFormat.[[Notation]] to notation.
-    number_format.set_notation(TRY(notation.as_string().utf8_string_view()));
+    number_format.set_notation(notation.as_string().utf8_string_view());
 
     // 20. Perform ? SetNumberFormatDigitOptions(numberFormat, options, mnfdDefault, mxfdDefault, notation).
     TRY(set_number_format_digit_options(vm, number_format, *options, default_min_fraction_digits, default_max_fraction_digits, number_format.notation()));
@@ -176,7 +176,7 @@ ThrowCompletionOr<NumberFormat*> initialize_number_format(VM& vm, NumberFormat&
     // 23. If notation is "compact", then
     if (number_format.notation() == NumberFormat::Notation::Compact) {
         // a. Set numberFormat.[[CompactDisplay]] to compactDisplay.
-        number_format.set_compact_display(TRY(compact_display.as_string().utf8_string_view()));
+        number_format.set_compact_display(compact_display.as_string().utf8_string_view());
 
         // b. Set defaultUseGrouping to "min2".
         default_use_grouping = "min2"sv;
@@ -205,7 +205,7 @@ ThrowCompletionOr<NumberFormat*> initialize_number_format(VM& vm, NumberFormat&
     auto sign_display = TRY(get_option(vm, *options, vm.names.signDisplay, OptionType::String, { "auto"sv, "never"sv, "always"sv, "exceptZero"sv, "negative"sv }, "auto"sv));
 
     // 30. Set numberFormat.[[SignDisplay]] to signDisplay.
-    number_format.set_sign_display(TRY(sign_display.as_string().utf8_string_view()));
+    number_format.set_sign_display(sign_display.as_string().utf8_string_view());
 
     // 31. Return numberFormat.
     return &number_format;
@@ -234,7 +234,7 @@ ThrowCompletionOr<void> set_number_format_digit_options(VM& vm, NumberFormatBase
 
     // 7. Let roundingPriority be ? GetOption(options, "roundingPriority", string, « "auto", "morePrecision", "lessPrecision" », "auto").
     auto rounding_priority_option = TRY(get_option(vm, options, vm.names.roundingPriority, OptionType::String, { "auto"sv, "morePrecision"sv, "lessPrecision"sv }, "auto"sv));
-    auto rounding_priority = MUST_OR_THROW_OOM(rounding_priority_option.as_string().utf8_string_view());
+    auto rounding_priority = rounding_priority_option.as_string().utf8_string_view();
 
     // 8. Let roundingIncrement be ? GetNumberOption(options, "roundingIncrement", 1, 5000, 1).
     auto rounding_increment = TRY(get_number_option(vm, options, vm.names.roundingIncrement, 1, 5000, 1));
@@ -261,10 +261,10 @@ ThrowCompletionOr<void> set_number_format_digit_options(VM& vm, NumberFormatBase
     intl_object.set_rounding_increment(*rounding_increment);
 
     // 15. Set intlObj.[[RoundingMode]] to roundingMode.
-    intl_object.set_rounding_mode(TRY(rounding_mode.as_string().utf8_string_view()));
+    intl_object.set_rounding_mode(rounding_mode.as_string().utf8_string_view());
 
     // 16. Set intlObj.[[TrailingZeroDisplay]] to trailingZeroDisplay.
-    intl_object.set_trailing_zero_display(TRY(trailing_zero_display.as_string().utf8_string_view()));
+    intl_object.set_trailing_zero_display(trailing_zero_display.as_string().utf8_string_view());
 
     // 17. If mnsd is not undefined or mxsd is not undefined, then
     //     a. Let hasSd be true.
@@ -417,7 +417,7 @@ ThrowCompletionOr<void> set_number_format_unit_options(VM& vm, NumberFormat& int
     auto style = TRY(get_option(vm, options, vm.names.style, OptionType::String, { "decimal"sv, "percent"sv, "currency"sv, "unit"sv }, "decimal"sv));
 
     // 4. Set intlObj.[[Style]] to style.
-    intl_object.set_style(TRY(style.as_string().utf8_string_view()));
+    intl_object.set_style(style.as_string().utf8_string_view());
 
     // 5. Let currency be ? GetOption(options, "currency", string, empty, undefined).
     auto currency = TRY(get_option(vm, options, vm.names.currency, OptionType::String, {}, Empty {}));
@@ -430,7 +430,7 @@ ThrowCompletionOr<void> set_number_format_unit_options(VM& vm, NumberFormat& int
     }
     // 7. Else,
     //     a. If IsWellFormedCurrencyCode(currency) is false, throw a RangeError exception.
-    else if (!is_well_formed_currency_code(TRY(currency.as_string().utf8_string_view())))
+    else if (!is_well_formed_currency_code(currency.as_string().utf8_string_view()))
         return vm.throw_completion<RangeError>(ErrorType::OptionIsNotValidValue, currency, "currency"sv);
 
     // 8. Let currencyDisplay be ? GetOption(options, "currencyDisplay", string, « "code", "symbol", "narrowSymbol", "name" », "symbol").
@@ -450,7 +450,7 @@ ThrowCompletionOr<void> set_number_format_unit_options(VM& vm, NumberFormat& int
     }
     // 12. Else,
     //     a. If ! IsWellFormedUnitIdentifier(unit) is false, throw a RangeError exception.
-    else if (!is_well_formed_unit_identifier(TRY(unit.as_string().utf8_string_view())))
+    else if (!is_well_formed_unit_identifier(unit.as_string().utf8_string_view()))
         return vm.throw_completion<RangeError>(ErrorType::OptionIsNotValidValue, unit, "unit"sv);
 
     // 13. Let unitDisplay be ? GetOption(options, "unitDisplay", string, « "short", "narrow", "long" », "short").
@@ -459,22 +459,22 @@ ThrowCompletionOr<void> set_number_format_unit_options(VM& vm, NumberFormat& int
     // 14. If style is "currency", then
     if (intl_object.style() == NumberFormat::Style::Currency) {
         // a. Set intlObj.[[Currency]] to the ASCII-uppercase of currency.
-        intl_object.set_currency(TRY_OR_THROW_OOM(vm, TRY(currency.as_string().utf8_string()).to_uppercase()));
+        intl_object.set_currency(TRY_OR_THROW_OOM(vm, currency.as_string().utf8_string().to_uppercase()));
 
         // c. Set intlObj.[[CurrencyDisplay]] to currencyDisplay.
-        intl_object.set_currency_display(TRY(currency_display.as_string().utf8_string_view()));
+        intl_object.set_currency_display(currency_display.as_string().utf8_string_view());
 
         // d. Set intlObj.[[CurrencySign]] to currencySign.
-        intl_object.set_currency_sign(TRY(currency_sign.as_string().utf8_string_view()));
+        intl_object.set_currency_sign(currency_sign.as_string().utf8_string_view());
     }
 
     // 15. If style is "unit", then
     if (intl_object.style() == NumberFormat::Style::Unit) {
         // a. Set intlObj.[[Unit]] to unit.
-        intl_object.set_unit(TRY(unit.as_string().utf8_string()));
+        intl_object.set_unit(unit.as_string().utf8_string());
 
         // b. Set intlObj.[[UnitDisplay]] to unitDisplay.
-        intl_object.set_unit_display(TRY(unit_display.as_string().utf8_string_view()));
+        intl_object.set_unit_display(unit_display.as_string().utf8_string_view());
     }
 
     return {};

Userland/Libraries/LibJS/Runtime/Intl/PluralRulesConstructor.cpp

@@ -94,7 +94,7 @@ ThrowCompletionOr<PluralRules*> initialize_plural_rules(VM& vm, PluralRules& plu
     auto type = TRY(get_option(vm, *options, vm.names.type, OptionType::String, AK::Array { "cardinal"sv, "ordinal"sv }, "cardinal"sv));
 
     // 7. Set pluralRules.[[Type]] to t.
-    plural_rules.set_type(TRY(type.as_string().utf8_string_view()));
+    plural_rules.set_type(type.as_string().utf8_string_view());
 
     // 8. Perform ? SetNumberFormatDigitOptions(pluralRules, options, +0𝔽, 3𝔽, "standard").
     TRY(set_number_format_digit_options(vm, plural_rules, *options, 0, 3, NumberFormat::Notation::Standard));

Userland/Libraries/LibJS/Runtime/Intl/RelativeTimeFormatConstructor.cpp

@@ -101,11 +101,11 @@ ThrowCompletionOr<RelativeTimeFormat*> initialize_relative_time_format(VM& vm, R
     // 7. If numberingSystem is not undefined, then
     if (!numbering_system.is_undefined()) {
         // a. If numberingSystem does not match the Unicode Locale Identifier type nonterminal, throw a RangeError exception.
-        if (!::Locale::is_type_identifier(TRY(numbering_system.as_string().utf8_string_view())))
+        if (!::Locale::is_type_identifier(numbering_system.as_string().utf8_string_view()))
             return vm.throw_completion<RangeError>(ErrorType::OptionIsNotValidValue, numbering_system, "numberingSystem"sv);
 
         // 8. Set opt.[[nu]] to numberingSystem.
-        opt.nu = TRY(numbering_system.as_string().utf8_string());
+        opt.nu = numbering_system.as_string().utf8_string();
     }
 
     // 9. Let localeData be %RelativeTimeFormat%.[[LocaleData]].
@@ -129,13 +129,13 @@ ThrowCompletionOr<RelativeTimeFormat*> initialize_relative_time_format(VM& vm, R
     auto style = TRY(get_option(vm, *options, vm.names.style, OptionType::String, { "long"sv, "short"sv, "narrow"sv }, "long"sv));
 
     // 16. Set relativeTimeFormat.[[Style]] to style.
-    relative_time_format.set_style(TRY(style.as_string().utf8_string_view()));
+    relative_time_format.set_style(style.as_string().utf8_string_view());
 
     // 17. Let numeric be ? GetOption(options, "numeric", string, « "always", "auto" », "always").
     auto numeric = TRY(get_option(vm, *options, vm.names.numeric, OptionType::String, { "always"sv, "auto"sv }, "always"sv));
 
     // 18. Set relativeTimeFormat.[[Numeric]] to numeric.
-    relative_time_format.set_numeric(TRY(numeric.as_string().utf8_string_view()));
+    relative_time_format.set_numeric(numeric.as_string().utf8_string_view());
 
     // 19. Let relativeTimeFormat.[[NumberFormat]] be ! Construct(%NumberFormat%, « locale »).
     auto number_format = MUST(construct(vm, realm.intrinsics().intl_number_format_constructor(), PrimitiveString::create(vm, locale)));

Userland/Libraries/LibJS/Runtime/Intl/SegmenterConstructor.cpp

@@ -81,7 +81,7 @@ ThrowCompletionOr<NonnullGCPtr<Object>> SegmenterConstructor::construct(Function
     auto granularity = TRY(get_option(vm, *options, vm.names.granularity, OptionType::String, { "grapheme"sv, "word"sv, "sentence"sv }, "grapheme"sv));
 
     // 13. Set segmenter.[[SegmenterGranularity]] to granularity.
-    segmenter->set_segmenter_granularity(TRY(granularity.as_string().utf8_string_view()));
+    segmenter->set_segmenter_granularity(granularity.as_string().utf8_string_view());
 
     // 14. Return segmenter.
     return segmenter;

Userland/Libraries/LibJS/Runtime/PrimitiveString.cpp

@@ -74,14 +74,13 @@ bool PrimitiveString::is_empty() const
     VERIFY_NOT_REACHED();
 }
 
-ThrowCompletionOr<String> PrimitiveString::utf8_string() const
+String PrimitiveString::utf8_string() const
 {
-    auto& vm = this->vm();
     resolve_rope_if_needed(EncodingPreference::UTF8);
 
     if (!has_utf8_string()) {
         if (has_deprecated_string())
-            m_utf8_string = TRY_OR_THROW_OOM(vm, String::from_deprecated_string(*m_deprecated_string));
+            m_utf8_string = MUST(String::from_deprecated_string(*m_deprecated_string));
         else if (has_utf16_string())
             m_utf8_string = m_utf16_string->to_utf8();
         else
@@ -91,9 +90,9 @@ ThrowCompletionOr<String> PrimitiveString::utf8_string() const
     return *m_utf8_string;
 }
 
-ThrowCompletionOr<StringView> PrimitiveString::utf8_string_view() const
+StringView PrimitiveString::utf8_string_view() const
 {
-    (void)TRY(utf8_string());
+    (void)utf8_string();
     return m_utf8_string->bytes_as_string_view();
 }
 
@@ -292,14 +291,14 @@ void PrimitiveString::resolve_rope_if_needed(EncodingPreference preference) cons
     for (auto const* current : pieces) {
         if (!previous) {
             // This is the very first piece, just append it and continue.
-            builder.append(MUST(current->utf8_string()));
+            builder.append(current->utf8_string());
             previous = current;
             continue;
         }
 
         // Get the UTF-8 representations for both strings.
-        auto current_string_as_utf8 = MUST(current->utf8_string_view());
-        auto previous_string_as_utf8 = MUST(previous->utf8_string_view());
+        auto current_string_as_utf8 = current->utf8_string_view();
+        auto previous_string_as_utf8 = previous->utf8_string_view();
 
         // NOTE: Now we need to look at the end of the previous string and the start
         //       of the current string, to see if they should be combined into a surrogate.

Userland/Libraries/LibJS/Runtime/PrimitiveString.h

@@ -38,8 +38,8 @@ public:
 
     bool is_empty() const;
 
-    ThrowCompletionOr<String> utf8_string() const;
-    ThrowCompletionOr<StringView> utf8_string_view() const;
+    [[nodiscard]] String utf8_string() const;
+    [[nodiscard]] StringView utf8_string_view() const;
     bool has_utf8_string() const { return m_utf8_string.has_value(); }
 
     ThrowCompletionOr<DeprecatedString> deprecated_string() const;

Userland/Libraries/LibJS/Runtime/ShadowRealm.cpp

@@ -282,7 +282,7 @@ ThrowCompletionOr<Value> shadow_realm_import_value(VM& vm, DeprecatedString spec
     // NOTE: Even though the spec tells us to use %ThrowTypeError%, it's not observable if we actually do.
     // Throw a nicer TypeError forwarding the import error message instead (we know the argument is an Error object).
     auto throw_type_error = NativeFunction::create(realm, {}, [](auto& vm) -> ThrowCompletionOr<Value> {
-        return vm.template throw_completion<TypeError>(TRY(vm.argument(0).as_object().get_without_side_effects(vm.names.message).as_string().utf8_string()));
+        return vm.template throw_completion<TypeError>(vm.argument(0).as_object().get_without_side_effects(vm.names.message).as_string().utf8_string());
     });
 
     // 13. Return PerformPromiseThen(innerCapability.[[Promise]], onFulfilled, callerRealm.[[Intrinsics]].[[%ThrowTypeError%]], promiseCapability).

Userland/Libraries/LibJS/Runtime/Temporal/AbstractOperations.cpp

@@ -146,7 +146,7 @@ ThrowCompletionOr<Value> get_option(VM& vm, Object const& options, PropertyKey c
     if (!values.is_empty()) {
         // NOTE: Every location in the spec that invokes GetOption with type=boolean also has values=undefined.
         VERIFY(value.is_string());
-        if (auto value_string = TRY(value.as_string().utf8_string()); !values.contains_slow(value_string))
+        if (auto value_string = value.as_string().utf8_string(); !values.contains_slow(value_string))
             return vm.throw_completion<RangeError>(ErrorType::OptionIsNotValidValue, value_string, property.as_string());
     }
 
@@ -530,7 +530,7 @@ ThrowCompletionOr<Optional<String>> get_temporal_unit(VM& vm, Object const& norm
 
     auto value = option_value.is_undefined()
         ? Optional<String> {}
-        : TRY(option_value.as_string().utf8_string());
+        : option_value.as_string().utf8_string();
 
     // 11. If value is listed in the Plural column of Table 13, then
     for (auto const& row : temporal_units) {

Userland/Libraries/LibJS/Runtime/Temporal/Calendar.cpp

@@ -131,7 +131,7 @@ ThrowCompletionOr<Vector<String>> calendar_fields(VM& vm, Object& calendar, Vect
     Vector<String> result;
     TRY_OR_THROW_OOM(vm, result.try_ensure_capacity(list.size()));
     for (auto& value : list)
-        result.unchecked_append(TRY(value.as_string().utf8_string()));
+        result.unchecked_append(value.as_string().utf8_string());
     return result;
 }
 

Userland/Libraries/LibJS/Runtime/Temporal/CalendarPrototype.cpp

@@ -559,7 +559,7 @@ JS_DEFINE_NATIVE_FUNCTION(CalendarPrototype::fields)
             return *TRY(iterator_close(vm, iterator_record, move(completion)));
         }
 
-        auto next_value_string = TRY(next_value.as_string().utf8_string());
+        auto next_value_string = next_value.as_string().utf8_string();
 
         // iii. If fieldNames contains nextValue, then
         if (field_names.contains_slow(next_value)) {

Userland/Libraries/LibJS/Runtime/Temporal/ZonedDateTime.cpp

@@ -176,7 +176,7 @@ ThrowCompletionOr<ZonedDateTime*> to_temporal_zoned_date_time(VM& vm, Value item
             offset_behavior = OffsetBehavior::Wall;
         } else {
             // NOTE: Not in the spec, since it directly assigns to offsetString in step i, but we can't do it there as it's a type mismatch.
-            offset_string = TRY(offset_string_value.as_string().utf8_string());
+            offset_string = offset_string_value.as_string().utf8_string();
         }
 
         // l. Let result be ? InterpretTemporalDateTimeFields(calendar, fields, options).

Userland/Libraries/LibJS/Runtime/Temporal/ZonedDateTimePrototype.cpp

@@ -801,7 +801,7 @@ JS_DEFINE_NATIVE_FUNCTION(ZonedDateTimePrototype::with)
 
     // 18. Assert: Type(offsetString) is String.
     VERIFY(offset_string_value.is_string());
-    auto offset_string = TRY(offset_string_value.as_string().utf8_string());
+    auto offset_string = offset_string_value.as_string().utf8_string();
 
     // 19. Let dateTimeResult be ? InterpretTemporalDateTimeFields(calendar, fields, options).
     auto date_time_result = TRY(interpret_temporal_date_time_fields(vm, calendar, *fields, options));

Userland/Libraries/LibJS/Runtime/Value.cpp

@@ -370,18 +370,7 @@ ErrorOr<String> Value::to_string_without_side_effects() const
     case INT32_TAG:
         return String::number(as_i32());
     case STRING_TAG:
-        if (auto string = as_string().utf8_string(); string.is_throw_completion()) {
-            auto completion = string.release_error();
-
-            // We can't explicitly check for OOM because InternalError does not store the ErrorType
-            VERIFY(completion.value().has_value());
-            VERIFY(completion.value()->is_object());
-            VERIFY(is<InternalError>(completion.value()->as_object()));
-
-            return AK::Error::from_errno(ENOMEM);
-        } else {
-            return string.release_value();
-        }
+        return as_string().utf8_string();
     case SYMBOL_TAG:
         return as_symbol().descriptive_string();
     case BIGINT_TAG:
@@ -414,7 +403,7 @@ ThrowCompletionOr<String> Value::to_string(VM& vm) const
     switch (m_value.tag) {
     // 1. If argument is a String, return argument.
     case STRING_TAG:
-        return TRY(as_string().utf8_string());
+        return as_string().utf8_string();
     // 2. If argument is a Symbol, throw a TypeError exception.
     case SYMBOL_TAG:
         return vm.throw_completion<TypeError>(ErrorType::Convert, "symbol", "string");

Userland/Libraries/LibWeb/DOM/Element.cpp

@@ -1573,7 +1573,7 @@ void Element::enqueue_a_custom_element_callback_reaction(FlyString const& callba
         VERIFY(!arguments.is_empty());
         auto& attribute_name_value = arguments.first();
         VERIFY(attribute_name_value.is_string());
-        auto attribute_name = attribute_name_value.as_string().utf8_string().release_allocated_value_but_fixme_should_propagate_errors();
+        auto attribute_name = attribute_name_value.as_string().utf8_string();
 
         // 2. If definition's observed attributes does not contain attributeName, then return.
         if (!definition->observed_attributes().contains_slow(attribute_name))

Userland/Libraries/LibWeb/HTML/StructuredSerialize.cpp

@@ -166,9 +166,7 @@ private:
 
     WebIDL::ExceptionOr<void> serialize_string(Vector<u32>& vector, JS::PrimitiveString const& primitive_string)
     {
-        auto string = TRY(Bindings::throw_dom_exception_if_needed(m_vm, [&primitive_string]() {
-            return primitive_string.utf8_string();
-        }));
+        auto string = primitive_string.utf8_string();
         TRY(serialize_string(vector, string));
         return {};
     }

Userland/Libraries/LibWeb/Infra/JSON.cpp

@@ -52,7 +52,7 @@ WebIDL::ExceptionOr<String> serialize_javascript_value_to_json_string(JS::VM& vm
     VERIFY(result.is_string());
 
     // 4. Return result.
-    return TRY(result.as_string().utf8_string());
+    return result.as_string().utf8_string();
 }
 
 // https://infra.spec.whatwg.org/#serialize-a-javascript-value-to-json-bytes

Userland/Libraries/LibWeb/Streams/AbstractOperations.cpp

@@ -3131,7 +3131,7 @@ WebIDL::ExceptionOr<JS::NonnullGCPtr<WebIDL::Promise>> transform_stream_default_
             TRY(transform_stream_error(stream, reason));
 
             // 2. Throw readable.[[storedError]].
-            return WebIDL::SimpleException { WebIDL::SimpleExceptionType::TypeError, TRY(readable->stored_error().as_string().utf8_string_view()) };
+            return WebIDL::SimpleException { WebIDL::SimpleExceptionType::TypeError, readable->stored_error().as_string().utf8_string() };
         });
 
     return WebIDL::create_resolved_promise(realm, react_result);