js: Print ConsoleMessages and color the output based on their kind :^)

Userland/js.cpp

@@ -84,7 +84,6 @@ String read_next_piece()
     StringBuilder piece;
 
     do {
-
         String line = s_editor->get_line(prompt_for_level(s_repl_line_level));
         s_editor->add_to_history(line);
 
@@ -389,6 +388,37 @@ void sigint_handler()
     interrupt_interpreter();
 }
 
+void console_message_handler(JS::ConsoleMessage& message)
+{
+    switch (message.kind) {
+    case JS::ConsoleMessageKind::Count:
+    case JS::ConsoleMessageKind::Log:
+    case JS::ConsoleMessageKind::Info:
+    case JS::ConsoleMessageKind::Trace:
+        puts(message.text.characters());
+        break;
+    case JS::ConsoleMessageKind::Debug:
+        printf("\033[36;1m");
+        puts(message.text.characters());
+        printf("\033[0m");
+        break;
+    case JS::ConsoleMessageKind::Warn:
+        printf("\033[33;1m");
+        puts(message.text.characters());
+        printf("\033[0m");
+        break;
+    case JS::ConsoleMessageKind::Error:
+        printf("\033[31;1m");
+        puts(message.text.characters());
+        printf("\033[0m");
+        break;
+    case JS::ConsoleMessageKind::Clear:
+        printf("\033[3J\033[H\033[2J");
+        fflush(stdout);
+        break;
+    }
+};
+
 int main(int argc, char** argv)
 {
     bool gc_on_every_allocation = false;
@@ -416,6 +446,7 @@ int main(int argc, char** argv)
 
     if (script_path == nullptr) {
         interpreter = JS::Interpreter::create<ReplObject>();
+        interpreter->console().on_new_message = console_message_handler;
         interpreter->heap().set_should_collect_on_every_allocation(gc_on_every_allocation);
         if (test_mode)
             enable_test_mode(*interpreter);
@@ -638,6 +669,7 @@ int main(int argc, char** argv)
         repl(*interpreter);
     } else {
         interpreter = JS::Interpreter::create<JS::GlobalObject>();
+        interpreter->console().on_new_message = console_message_handler;
         interpreter->heap().set_should_collect_on_every_allocation(gc_on_every_allocation);
         if (test_mode)
             enable_test_mode(*interpreter);