LibJS: Implement console.count()

Author: https://github.com/emanuele6
Commit: https://github.com/SerenityOS/serenity/commit/8c60ba1e422
Pull-request: https://github.com/SerenityOS/serenity/pull/2045

Libraries/LibJS/Interpreter.h

@@ -162,6 +162,8 @@ public:
 
     Value last_value() const { return m_last_value; }
 
+    HashMap<String, unsigned>& console_counters() { return m_console_counters; }
+
 private:
     Interpreter();
 
@@ -177,6 +179,8 @@ private:
     Exception* m_exception { nullptr };
 
     ScopeType m_unwind_until { ScopeType::None };
+
+    HashMap<String, unsigned> m_console_counters;
 };
 
 }

Libraries/LibJS/Runtime/ConsoleObject.cpp

@@ -1,6 +1,7 @@
 /*
  * Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
  * Copyright (c) 2020, Linus Groh <mail@linusgroh.de>
+ * Copyright (c) 2020, Emanuele Torre <torreemanuele6@gmail.com>
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -27,6 +28,7 @@
 
 #include <AK/FlyString.h>
 #include <AK/Function.h>
+#include <AK/HashMap.h>
 #include <LibJS/Interpreter.h>
 #include <LibJS/Runtime/ConsoleObject.h>
 #include <LibJS/Runtime/GlobalObject.h>
@@ -53,6 +55,7 @@ ConsoleObject::ConsoleObject()
     put_native_function("warn", warn);
     put_native_function("error", error);
     put_native_function("trace", trace);
+    put_native_function("count", count);
 }
 
 ConsoleObject::~ConsoleObject()
@@ -109,4 +112,25 @@ Value ConsoleObject::trace(Interpreter& interpreter)
     return js_undefined();
 }
 
+Value ConsoleObject::count(Interpreter& interpreter)
+{
+    String counter_name;
+    if (!interpreter.argument_count())
+        counter_name = "default";
+    else
+        counter_name = interpreter.argument(0).to_string();
+
+    auto& counters = interpreter.console_counters();
+    auto counter_value = counters.get(counter_name);
+
+    if (counter_value.has_value()) {
+        printf("%s: %d\n", counter_name.characters(), counter_value.value() + 1);
+        counters.set(counter_name, counter_value.value() + 1);
+    } else {
+        printf("%s: 1\n", counter_name.characters());
+        counters.set(counter_name, 1);
+    }
+    return js_undefined();
+}
+
 }

Libraries/LibJS/Runtime/ConsoleObject.h

@@ -44,6 +44,7 @@ private:
     static Value warn(Interpreter&);
     static Value error(Interpreter&);
     static Value trace(Interpreter&);
+    static Value count(Interpreter&);
 };
 
 }