LibJS+Userland: Port the JS Console object and direct callers to String

Author: https://github.com/trflynn89
Commit: https://github.com/SerenityOS/serenity/commit/3b4879d29b
Pull-request: https://github.com/SerenityOS/serenity/pull/17415

Userland/Libraries/LibJS/Console.cpp

@@ -10,6 +10,7 @@
 #include <LibJS/Runtime/AbstractOperations.h>
 #include <LibJS/Runtime/StringConstructor.h>
 #include <LibJS/Runtime/Temporal/Duration.h>
+#include <LibJS/Runtime/ThrowableStringBuilder.h>
 
 namespace JS {
 
@@ -98,29 +99,37 @@ ThrowCompletionOr<Value> Console::trace()
     auto& execution_context_stack = vm.execution_context_stack();
     // NOTE: -2 to skip the console.trace() execution context
     for (ssize_t i = execution_context_stack.size() - 2; i >= 0; --i) {
-        auto& function_name = execution_context_stack[i]->function_name;
-        trace.stack.append(function_name.is_empty() ? "<anonymous>" : function_name);
+        auto const& function_name = execution_context_stack[i]->function_name;
+        trace.stack.append(function_name.is_empty()
+                ? TRY_OR_THROW_OOM(vm, String::from_utf8("<anonymous>"sv))
+                : TRY_OR_THROW_OOM(vm, String::from_deprecated_string(function_name)));
     }
 
     // 2. Optionally, let formattedData be the result of Formatter(data), and incorporate formattedData as a label for trace.
     if (vm.argument_count() > 0) {
-        StringBuilder builder;
         auto data = vm_arguments();
         auto formatted_data = TRY(m_client->formatter(data));
-        trace.label = TRY(value_vector_to_deprecated_string(formatted_data));
+        trace.label = TRY(value_vector_to_string(formatted_data));
     }
 
     // 3. Perform Printer("trace", « trace »).
     return m_client->printer(Console::LogLevel::Trace, trace);
 }
 
+static ThrowCompletionOr<String> label_or_fallback(VM& vm, StringView fallback)
+{
+    return vm.argument_count() > 0
+        ? vm.argument(0).to_string(vm)
+        : TRY_OR_THROW_OOM(vm, String::from_utf8(fallback));
+}
+
 // 1.2.1. count(label), https://console.spec.whatwg.org/#count
 ThrowCompletionOr<Value> Console::count()
 {
     auto& vm = realm().vm();
 
     // NOTE: "default" is the default value in the IDL. https://console.spec.whatwg.org/#ref-for-count
-    auto label = vm.argument_count() ? TRY(vm.argument(0).to_deprecated_string(vm)) : "default";
+    auto label = TRY(label_or_fallback(vm, "default"sv));
 
     // 1. Let map be the associated count map.
     auto& map = m_counters;
@@ -135,11 +144,11 @@ ThrowCompletionOr<Value> Console::count()
     }
 
     // 4. Let concat be the concatenation of label, U+003A (:), U+0020 SPACE, and ToString(map[label]).
-    DeprecatedString concat = DeprecatedString::formatted("{}: {}", label, map.get(label).value());
+    auto concat = TRY_OR_THROW_OOM(vm, String::formatted("{}: {}", label, map.get(label).value()));
 
     // 5. Perform Logger("count", « concat »).
     MarkedVector<Value> concat_as_vector { vm.heap() };
-    concat_as_vector.append(PrimitiveString::create(vm, concat));
+    concat_as_vector.append(PrimitiveString::create(vm, move(concat)));
     if (m_client)
         TRY(m_client->logger(LogLevel::Count, concat_as_vector));
     return js_undefined();
@@ -151,7 +160,7 @@ ThrowCompletionOr<Value> Console::count_reset()
     auto& vm = realm().vm();
 
     // NOTE: "default" is the default value in the IDL. https://console.spec.whatwg.org/#ref-for-countreset
-    auto label = vm.argument_count() ? TRY(vm.argument(0).to_deprecated_string(vm)) : "default";
+    auto label = TRY(label_or_fallback(vm, "default"sv));
 
     // 1. Let map be the associated count map.
     auto& map = m_counters;
@@ -164,10 +173,10 @@ ThrowCompletionOr<Value> Console::count_reset()
     else {
         // 1. Let message be a string without any formatting specifiers indicating generically
         //    that the given label does not have an associated count.
-        auto message = DeprecatedString::formatted("\"{}\" doesn't have a count", label);
+        auto message = TRY_OR_THROW_OOM(vm, String::formatted("\"{}\" doesn't have a count", label));
         // 2. Perform Logger("countReset", « message »);
         MarkedVector<Value> message_as_vector { vm.heap() };
-        message_as_vector.append(PrimitiveString::create(vm, message));
+        message_as_vector.append(PrimitiveString::create(vm, move(message)));
         if (m_client)
             TRY(m_client->logger(LogLevel::CountReset, message_as_vector));
     }
@@ -212,9 +221,9 @@ ThrowCompletionOr<Value> Console::assert_()
         // 3. Otherwise:
         else {
             // 1. Let concat be the concatenation of message, U+003A (:), U+0020 SPACE, and first.
-            auto concat = PrimitiveString::create(vm, DeprecatedString::formatted("{}: {}", TRY(message->deprecated_string()), first.to_deprecated_string(vm).value()));
+            auto concat = TRY_OR_THROW_OOM(vm, String::formatted("{}: {}", TRY(message->utf8_string()), MUST(first.to_string(vm))));
             // 2. Set data[0] to concat.
-            data[0] = concat;
+            data[0] = PrimitiveString::create(vm, move(concat));
         }
     }
 
@@ -227,19 +236,21 @@ ThrowCompletionOr<Value> Console::assert_()
 // 1.3.1. group(...data), https://console.spec.whatwg.org/#group
 ThrowCompletionOr<Value> Console::group()
 {
+    auto& vm = realm().vm();
+
     // 1. Let group be a new group.
     Group group;
 
     // 2. If data is not empty, let groupLabel be the result of Formatter(data).
-    DeprecatedString group_label;
+    String group_label {};
     auto data = vm_arguments();
     if (!data.is_empty()) {
         auto formatted_data = TRY(m_client->formatter(data));
-        group_label = TRY(value_vector_to_deprecated_string(formatted_data));
+        group_label = TRY(value_vector_to_string(formatted_data));
     }
     // ... Otherwise, let groupLabel be an implementation-chosen label representing a group.
     else {
-        group_label = "Group";
+        group_label = TRY_OR_THROW_OOM(vm, String::from_utf8("Group"sv));
     }
 
     // 3. Incorporate groupLabel as a label for group.
@@ -261,19 +272,21 @@ ThrowCompletionOr<Value> Console::group()
 // 1.3.2. groupCollapsed(...data), https://console.spec.whatwg.org/#groupcollapsed
 ThrowCompletionOr<Value> Console::group_collapsed()
 {
+    auto& vm = realm().vm();
+
     // 1. Let group be a new group.
     Group group;
 
     // 2. If data is not empty, let groupLabel be the result of Formatter(data).
-    DeprecatedString group_label;
+    String group_label {};
     auto data = vm_arguments();
     if (!data.is_empty()) {
         auto formatted_data = TRY(m_client->formatter(data));
-        group_label = TRY(value_vector_to_deprecated_string(formatted_data));
+        group_label = TRY(value_vector_to_string(formatted_data));
     }
     // ... Otherwise, let groupLabel be an implementation-chosen label representing a group.
     else {
-        group_label = "Group";
+        group_label = TRY_OR_THROW_OOM(vm, String::from_utf8("Group"sv));
     }
 
     // 3. Incorporate groupLabel as a label for group.
@@ -312,14 +325,17 @@ ThrowCompletionOr<Value> Console::time()
     auto& vm = realm().vm();
 
     // NOTE: "default" is the default value in the IDL. https://console.spec.whatwg.org/#ref-for-time
-    auto label = vm.argument_count() ? TRY(vm.argument(0).to_deprecated_string(vm)) : "default";
+    auto label = TRY(label_or_fallback(vm, "default"sv));
 
     // 1. If the associated timer table contains an entry with key label, return, optionally reporting
-    // a warning to the console indicating that a timer with label `label` has already been started.
+    //    a warning to the console indicating that a timer with label `label` has already been started.
     if (m_timer_table.contains(label)) {
         if (m_client) {
             MarkedVector<Value> timer_already_exists_warning_message_as_vector { vm.heap() };
-            timer_already_exists_warning_message_as_vector.append(PrimitiveString::create(vm, DeprecatedString::formatted("Timer '{}' already exists.", label)));
+
+            auto message = TRY_OR_THROW_OOM(vm, String::formatted("Timer '{}' already exists.", label));
+            timer_already_exists_warning_message_as_vector.append(PrimitiveString::create(vm, move(message)));
+
             TRY(m_client->printer(LogLevel::Warn, move(timer_already_exists_warning_message_as_vector)));
         }
         return js_undefined();
@@ -336,7 +352,7 @@ ThrowCompletionOr<Value> Console::time_log()
     auto& vm = realm().vm();
 
     // NOTE: "default" is the default value in the IDL. https://console.spec.whatwg.org/#ref-for-timelog
-    auto label = vm.argument_count() ? TRY(vm.argument(0).to_deprecated_string(vm)) : "default";
+    auto label = TRY(label_or_fallback(vm, "default"sv));
 
     // 1. Let timerTable be the associated timer table.
 
@@ -347,7 +363,10 @@ ThrowCompletionOr<Value> Console::time_log()
     if (maybe_start_time == m_timer_table.end()) {
         if (m_client) {
             MarkedVector<Value> timer_does_not_exist_warning_message_as_vector { vm.heap() };
-            timer_does_not_exist_warning_message_as_vector.append(PrimitiveString::create(vm, DeprecatedString::formatted("Timer '{}' does not exist.", label)));
+
+            auto message = TRY_OR_THROW_OOM(vm, String::formatted("Timer '{}' does not exist.", label));
+            timer_does_not_exist_warning_message_as_vector.append(PrimitiveString::create(vm, move(message)));
+
             TRY(m_client->printer(LogLevel::Warn, move(timer_does_not_exist_warning_message_as_vector)));
         }
         return js_undefined();
@@ -358,12 +377,12 @@ ThrowCompletionOr<Value> Console::time_log()
     auto duration = TRY(format_time_since(start_time));
 
     // 4. Let concat be the concatenation of label, U+003A (:), U+0020 SPACE, and duration.
-    auto concat = DeprecatedString::formatted("{}: {}", label, duration);
+    auto concat = TRY_OR_THROW_OOM(vm, String::formatted("{}: {}", label, duration));
 
     // 5. Prepend concat to data.
     MarkedVector<Value> data { vm.heap() };
     data.ensure_capacity(vm.argument_count());
-    data.append(PrimitiveString::create(vm, concat));
+    data.append(PrimitiveString::create(vm, move(concat)));
     for (size_t i = 1; i < vm.argument_count(); ++i)
         data.append(vm.argument(i));
 
@@ -379,7 +398,7 @@ ThrowCompletionOr<Value> Console::time_end()
     auto& vm = realm().vm();
 
     // NOTE: "default" is the default value in the IDL. https://console.spec.whatwg.org/#ref-for-timeend
-    auto label = vm.argument_count() ? TRY(vm.argument(0).to_deprecated_string(vm)) : "default";
+    auto label = TRY(label_or_fallback(vm, "default"sv));
 
     // 1. Let timerTable be the associated timer table.
 
@@ -390,7 +409,10 @@ ThrowCompletionOr<Value> Console::time_end()
     if (maybe_start_time == m_timer_table.end()) {
         if (m_client) {
             MarkedVector<Value> timer_does_not_exist_warning_message_as_vector { vm.heap() };
-            timer_does_not_exist_warning_message_as_vector.append(PrimitiveString::create(vm, DeprecatedString::formatted("Timer '{}' does not exist.", label)));
+
+            auto message = TRY_OR_THROW_OOM(vm, String::formatted("Timer '{}' does not exist.", label));
+            timer_does_not_exist_warning_message_as_vector.append(PrimitiveString::create(vm, move(message)));
+
             TRY(m_client->printer(LogLevel::Warn, move(timer_does_not_exist_warning_message_as_vector)));
         }
         return js_undefined();
@@ -404,12 +426,12 @@ ThrowCompletionOr<Value> Console::time_end()
     auto duration = TRY(format_time_since(start_time));
 
     // 5. Let concat be the concatenation of label, U+003A (:), U+0020 SPACE, and duration.
-    auto concat = DeprecatedString::formatted("{}: {}", label, duration);
+    auto concat = TRY_OR_THROW_OOM(vm, String::formatted("{}: {}", label, duration));
 
     // 6. Perform Printer("timeEnd", « concat »).
     if (m_client) {
         MarkedVector<Value> concat_as_vector { vm.heap() };
-        concat_as_vector.append(PrimitiveString::create(vm, concat));
+        concat_as_vector.append(PrimitiveString::create(vm, move(concat)));
         TRY(m_client->printer(LogLevel::TimeEnd, move(concat_as_vector)));
     }
     return js_undefined();
@@ -427,7 +449,7 @@ MarkedVector<Value> Console::vm_arguments()
     return arguments;
 }
 
-void Console::output_debug_message(LogLevel log_level, DeprecatedString const& output) const
+void Console::output_debug_message(LogLevel log_level, String const& output) const
 {
     switch (log_level) {
     case Console::LogLevel::Debug:
@@ -457,43 +479,49 @@ void Console::report_exception(JS::Error const& exception, bool in_promise) cons
         m_client->report_exception(exception, in_promise);
 }
 
-ThrowCompletionOr<DeprecatedString> Console::value_vector_to_deprecated_string(MarkedVector<Value> const& values)
+ThrowCompletionOr<String> Console::value_vector_to_string(MarkedVector<Value> const& values)
 {
     auto& vm = realm().vm();
-    StringBuilder builder;
+    ThrowableStringBuilder builder(vm);
+
     for (auto const& item : values) {
         if (!builder.is_empty())
-            builder.append(' ');
-        builder.append(TRY(item.to_deprecated_string(vm)));
+            MUST_OR_THROW_OOM(builder.append(' '));
+
+        MUST_OR_THROW_OOM(builder.append(TRY(item.to_string(vm))));
     }
-    return builder.to_deprecated_string();
+
+    return builder.to_string();
 }
 
-ThrowCompletionOr<DeprecatedString> Console::format_time_since(Core::ElapsedTimer timer)
+ThrowCompletionOr<String> Console::format_time_since(Core::ElapsedTimer timer)
 {
     auto& vm = realm().vm();
 
     auto elapsed_ms = timer.elapsed_time().to_milliseconds();
     auto duration = TRY(Temporal::balance_duration(vm, 0, 0, 0, 0, elapsed_ms, 0, "0"_sbigint, "year"sv));
 
-    auto append = [&](StringBuilder& builder, auto format, auto... number) {
+    auto append = [&](ThrowableStringBuilder& builder, auto format, auto number) -> ThrowCompletionOr<void> {
         if (!builder.is_empty())
-            builder.append(' ');
-        builder.appendff(format, number...);
+            MUST_OR_THROW_OOM(builder.append(' '));
+        MUST_OR_THROW_OOM(builder.appendff(format, number));
+        return {};
     };
-    StringBuilder builder;
+
+    ThrowableStringBuilder builder(vm);
+
     if (duration.days > 0)
-        append(builder, "{:.0} day(s)"sv, duration.days);
+        MUST_OR_THROW_OOM(append(builder, "{:.0} day(s)"sv, duration.days));
     if (duration.hours > 0)
-        append(builder, "{:.0} hour(s)"sv, duration.hours);
+        MUST_OR_THROW_OOM(append(builder, "{:.0} hour(s)"sv, duration.hours));
     if (duration.minutes > 0)
-        append(builder, "{:.0} minute(s)"sv, duration.minutes);
+        MUST_OR_THROW_OOM(append(builder, "{:.0} minute(s)"sv, duration.minutes));
     if (duration.seconds > 0 || duration.milliseconds > 0) {
         double combined_seconds = duration.seconds + (0.001 * duration.milliseconds);
-        append(builder, "{:.3} seconds"sv, combined_seconds);
+        MUST_OR_THROW_OOM(append(builder, "{:.3} seconds"sv, combined_seconds));
     }
 
-    return builder.to_deprecated_string();
+    return builder.to_string();
 }
 
 // 2.1. Logger(logLevel, args), https://console.spec.whatwg.org/#logger
@@ -539,7 +567,7 @@ ThrowCompletionOr<MarkedVector<Value>> ConsoleClient::formatter(MarkedVector<Val
         return args;
 
     // 2. Let target be the first element of args.
-    auto target = (!args.is_empty()) ? TRY(args.first().to_deprecated_string(vm)) : "";
+    auto target = (!args.is_empty()) ? TRY(args.first().to_string(vm)) : String {};
 
     // 3. Let current be the second element of args.
     auto current = (args.size() > 1) ? args[1] : js_undefined();
@@ -621,19 +649,19 @@ ThrowCompletionOr<MarkedVector<Value>> ConsoleClient::formatter(MarkedVector<Val
         // 6. TODO: process %c
         else if (specifier == "%c"sv) {
             // NOTE: This has no spec yet. `%c` specifiers treat the argument as CSS styling for the log message.
-            add_css_style_to_current_message(TRY(current.to_deprecated_string(vm)));
+            add_css_style_to_current_message(TRY(current.to_string(vm)));
             converted = PrimitiveString::create(vm, String {});
         }
 
         // 7. If any of the previous steps set converted, replace specifier in target with converted.
         if (converted.has_value())
-            target = target.replace(specifier, TRY(converted->to_deprecated_string(vm)), ReplaceMode::FirstOnly);
+            target = TRY_OR_THROW_OOM(vm, target.replace(specifier, TRY(converted->to_string(vm)), ReplaceMode::FirstOnly));
     }
 
     // 7. Let result be a list containing target together with the elements of args starting from the third onward.
     MarkedVector<Value> result { vm.heap() };
     result.ensure_capacity(args.size() - 1);
-    result.empend(PrimitiveString::create(vm, target));
+    result.empend(PrimitiveString::create(vm, move(target)));
     for (size_t i = 2; i < args.size(); ++i)
         result.unchecked_append(args[i]);
 

Userland/Libraries/LibJS/Console.h

@@ -10,6 +10,7 @@
 #include <AK/Function.h>
 #include <AK/HashMap.h>
 #include <AK/Noncopyable.h>
+#include <AK/String.h>
 #include <AK/Vector.h>
 #include <LibCore/ElapsedTimer.h>
 #include <LibJS/Forward.h>
@@ -45,12 +46,12 @@ public:
     };
 
     struct Group {
-        DeprecatedString label;
+        String label;
     };
 
     struct Trace {
-        DeprecatedString label;
-        Vector<DeprecatedString> stack;
+        String label;
+        Vector<String> stack;
     };
 
     explicit Console(Realm&);
@@ -61,8 +62,8 @@ public:
 
     MarkedVector<Value> vm_arguments();
 
-    HashMap<DeprecatedString, unsigned>& counters() { return m_counters; }
-    HashMap<DeprecatedString, unsigned> const& counters() const { return m_counters; }
+    HashMap<String, unsigned>& counters() { return m_counters; }
+    HashMap<String, unsigned> const& counters() const { return m_counters; }
 
     ThrowCompletionOr<Value> debug();
     ThrowCompletionOr<Value> error();
@@ -81,18 +82,18 @@ public:
     ThrowCompletionOr<Value> time_log();
     ThrowCompletionOr<Value> time_end();
 
-    void output_debug_message(LogLevel log_level, DeprecatedString const& output) const;
+    void output_debug_message(LogLevel log_level, String const& output) const;
     void report_exception(JS::Error const&, bool) const;
 
 private:
-    ThrowCompletionOr<DeprecatedString> value_vector_to_deprecated_string(MarkedVector<Value> const&);
-    ThrowCompletionOr<DeprecatedString> format_time_since(Core::ElapsedTimer timer);
+    ThrowCompletionOr<String> value_vector_to_string(MarkedVector<Value> const&);
+    ThrowCompletionOr<String> format_time_since(Core::ElapsedTimer timer);
 
     Realm& m_realm;
     ConsoleClient* m_client { nullptr };
 
-    HashMap<DeprecatedString, unsigned> m_counters;
-    HashMap<DeprecatedString, Core::ElapsedTimer> m_timer_table;
+    HashMap<String, unsigned> m_counters;
+    HashMap<String, Core::ElapsedTimer> m_timer_table;
     Vector<Group> m_group_stack;
 };
 

Userland/Libraries/LibWeb/HTML/WorkerDebugConsoleClient.cpp

@@ -6,6 +6,9 @@
 
 #include <LibJS/Heap/MarkedVector.h>
 #include <LibJS/Runtime/Completion.h>
+#include <LibJS/Runtime/Realm.h>
+#include <LibJS/Runtime/ThrowableStringBuilder.h>
+#include <LibJS/Runtime/VM.h>
 #include <LibWeb/HTML/WorkerDebugConsoleClient.h>
 
 namespace Web::HTML {
@@ -31,16 +34,18 @@ void WorkerDebugConsoleClient::end_group()
 // 2.3. Printer(logLevel, args[, options]), https://console.spec.whatwg.org/#printer
 JS::ThrowCompletionOr<JS::Value> WorkerDebugConsoleClient::printer(JS::Console::LogLevel log_level, PrinterArguments arguments)
 {
-    DeprecatedString indent = DeprecatedString::repeated("  "sv, m_group_stack_depth);
+    auto& vm = m_console.realm().vm();
+
+    auto indent = TRY_OR_THROW_OOM(vm, String::repeated(' ', m_group_stack_depth * 2));
 
     if (log_level == JS::Console::LogLevel::Trace) {
         auto trace = arguments.get<JS::Console::Trace>();
-        StringBuilder builder;
+        JS::ThrowableStringBuilder builder(vm);
         if (!trace.label.is_empty())
-            builder.appendff("{}\033[36;1m{}\033[0m\n", indent, trace.label);
+            MUST_OR_THROW_OOM(builder.appendff("{}\033[36;1m{}\033[0m\n", indent, trace.label));
 
         for (auto& function_name : trace.stack)
-            builder.appendff("{}-> {}\n", indent, function_name);
+            MUST_OR_THROW_OOM(builder.appendff("{}-> {}\n", indent, function_name));
 
         dbgln("{}", builder.string_view());
         return JS::js_undefined();
@@ -53,7 +58,7 @@ JS::ThrowCompletionOr<JS::Value> WorkerDebugConsoleClient::printer(JS::Console::
         return JS::js_undefined();
     }
 
-    auto output = DeprecatedString::join(' ', arguments.get<JS::MarkedVector<JS::Value>>());
+    auto output = TRY_OR_THROW_OOM(vm, String::join(' ', arguments.get<JS::MarkedVector<JS::Value>>()));
     m_console.output_debug_message(log_level, output);
 
     switch (log_level) {

Userland/Services/WebContent/WebContentConsoleClient.cpp

@@ -12,6 +12,9 @@
 #include <LibJS/MarkupGenerator.h>
 #include <LibJS/Runtime/AbstractOperations.h>
 #include <LibJS/Runtime/ObjectEnvironment.h>
+#include <LibJS/Runtime/Realm.h>
+#include <LibJS/Runtime/ThrowableStringBuilder.h>
+#include <LibJS/Runtime/VM.h>
 #include <LibWeb/HTML/PolicyContainers.h>
 #include <LibWeb/HTML/Scripting/ClassicScript.h>
 #include <LibWeb/HTML/Scripting/Environments.h>
@@ -129,19 +132,21 @@ void WebContentConsoleClient::clear()
 // 2.3. Printer(logLevel, args[, options]), https://console.spec.whatwg.org/#printer
 JS::ThrowCompletionOr<JS::Value> WebContentConsoleClient::printer(JS::Console::LogLevel log_level, PrinterArguments arguments)
 {
+    auto& vm = m_console.realm().vm();
+
     auto styling = escape_html_entities(m_current_message_style.string_view());
     m_current_message_style.clear();
 
     if (log_level == JS::Console::LogLevel::Trace) {
         auto trace = arguments.get<JS::Console::Trace>();
-        StringBuilder html;
+        JS::ThrowableStringBuilder html(vm);
         if (!trace.label.is_empty())
-            html.appendff("<span class='title' style='{}'>{}</span><br>", styling, escape_html_entities(trace.label));
+            MUST_OR_THROW_OOM(html.appendff("<span class='title' style='{}'>{}</span><br>", styling, escape_html_entities(trace.label)));
 
-        html.append("<span class='trace'>"sv);
+        MUST_OR_THROW_OOM(html.append("<span class='trace'>"sv));
         for (auto& function_name : trace.stack)
-            html.appendff("-> {}<br>", escape_html_entities(function_name));
-        html.append("</span>"sv);
+            MUST_OR_THROW_OOM(html.appendff("-> {}<br>", escape_html_entities(function_name)));
+        MUST_OR_THROW_OOM(html.append("</span>"sv));
 
         print_html(html.string_view());
         return JS::js_undefined();
@@ -153,35 +158,36 @@ JS::ThrowCompletionOr<JS::Value> WebContentConsoleClient::printer(JS::Console::L
         return JS::js_undefined();
     }
 
-    auto output = DeprecatedString::join(' ', arguments.get<JS::MarkedVector<JS::Value>>());
+    auto output = TRY_OR_THROW_OOM(vm, String::join(' ', arguments.get<JS::MarkedVector<JS::Value>>()));
     m_console.output_debug_message(log_level, output);
 
-    StringBuilder html;
+    JS::ThrowableStringBuilder html(vm);
     switch (log_level) {
     case JS::Console::LogLevel::Debug:
-        html.appendff("<span class=\"debug\" style=\"{}\">(d) "sv, styling);
+        MUST_OR_THROW_OOM(html.appendff("<span class=\"debug\" style=\"{}\">(d) "sv, styling));
         break;
     case JS::Console::LogLevel::Error:
-        html.appendff("<span class=\"error\" style=\"{}\">(e) "sv, styling);
+        MUST_OR_THROW_OOM(html.appendff("<span class=\"error\" style=\"{}\">(e) "sv, styling));
         break;
     case JS::Console::LogLevel::Info:
-        html.appendff("<span class=\"info\" style=\"{}\">(i) "sv, styling);
+        MUST_OR_THROW_OOM(html.appendff("<span class=\"info\" style=\"{}\">(i) "sv, styling));
         break;
     case JS::Console::LogLevel::Log:
-        html.appendff("<span class=\"log\" style=\"{}\"> "sv, styling);
+        MUST_OR_THROW_OOM(html.appendff("<span class=\"log\" style=\"{}\"> "sv, styling));
         break;
     case JS::Console::LogLevel::Warn:
     case JS::Console::LogLevel::CountReset:
-        html.appendff("<span class=\"warn\" style=\"{}\">(w) "sv, styling);
+        MUST_OR_THROW_OOM(html.appendff("<span class=\"warn\" style=\"{}\">(w) "sv, styling));
         break;
     default:
-        html.appendff("<span style=\"{}\">"sv, styling);
+        MUST_OR_THROW_OOM(html.appendff("<span style=\"{}\">"sv, styling));
         break;
     }
 
-    html.append(escape_html_entities(output));
-    html.append("</span>"sv);
+    MUST_OR_THROW_OOM(html.append(escape_html_entities(output)));
+    MUST_OR_THROW_OOM(html.append("</span>"sv));
     print_html(html.string_view());
+
     return JS::js_undefined();
 }
 }

Userland/Utilities/js.cpp

@@ -21,6 +21,7 @@
 #include <LibJS/Runtime/ConsoleObject.h>
 #include <LibJS/Runtime/JSONObject.h>
 #include <LibJS/Runtime/StringPrototype.h>
+#include <LibJS/Runtime/ThrowableStringBuilder.h>
 #include <LibJS/SourceTextModule.h>
 #include <LibLine/Editor.h>
 #include <LibMain/Main.h>
@@ -531,16 +532,16 @@ public:
     // 2.3. Printer(logLevel, args[, options]), https://console.spec.whatwg.org/#printer
     virtual JS::ThrowCompletionOr<JS::Value> printer(JS::Console::LogLevel log_level, PrinterArguments arguments) override
     {
-        DeprecatedString indent = DeprecatedString::repeated("  "sv, m_group_stack_depth);
+        auto indent = TRY_OR_THROW_OOM(*g_vm, String::repeated(' ', m_group_stack_depth * 2));
 
         if (log_level == JS::Console::LogLevel::Trace) {
             auto trace = arguments.get<JS::Console::Trace>();
-            StringBuilder builder;
+            JS::ThrowableStringBuilder builder(*g_vm);
             if (!trace.label.is_empty())
-                builder.appendff("{}\033[36;1m{}\033[0m\n", indent, trace.label);
+                MUST_OR_THROW_OOM(builder.appendff("{}\033[36;1m{}\033[0m\n", indent, trace.label));
 
             for (auto& function_name : trace.stack)
-                builder.appendff("{}-> {}\n", indent, function_name);
+                MUST_OR_THROW_OOM(builder.appendff("{}-> {}\n", indent, function_name));
 
             outln("{}", builder.string_view());
             return JS::js_undefined();
@@ -553,7 +554,7 @@ public:
             return JS::js_undefined();
         }
 
-        auto output = DeprecatedString::join(' ', arguments.get<JS::MarkedVector<JS::Value>>());
+        auto output = TRY_OR_THROW_OOM(*g_vm, String::join(' ', arguments.get<JS::MarkedVector<JS::Value>>()));
 #ifdef AK_OS_SERENITY
         m_console.output_debug_message(log_level, output);
 #endif