LanguageServers: Add function to collect TODO entries in a document

Author: https://github.com/guerinoni
Commit: 26a7356e90
Pull-request: https://github.com/SerenityOS/serenity/pull/6614
Reviewed-by: https://github.com/alimpfard
Reviewed-by: https://github.com/itamar8910 ✅
Reviewed-by: https://github.com/linusg

Userland/DevTools/HackStudio/ToDoEntries.cpp

@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2021, Federico Guerinoni <guerinoni.federico@gmail.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include "ToDoEntries.h"
+
+namespace HackStudio {
+
+ToDoEntries& HackStudio::ToDoEntries::the()
+{
+    static ToDoEntries s_instance;
+    return s_instance;
+}
+
+void ToDoEntries::set_entries(const String& filename, const Vector<String>&& entries)
+{
+    m_document_to_entries.set(filename, move(entries));
+    if (on_update)
+        on_update();
+}
+
+Vector<ToDoEntryPair> ToDoEntries::get_entries()
+{
+    Vector<ToDoEntryPair> ret;
+    for (auto& it : m_document_to_entries)
+        for (auto& entry : it.value)
+            ret.append({ it.key, entry });
+
+    return ret;
+}
+
+}