LibGUI: Don't require passing model to FileSystemModel::Node APIs

The Node API was obnoxiously requiring you to pass the model into it
all the time, simply because nodes could not find their way back to
the containing model. This patch adds a back-reference to the model
and simplifies the API.

5 files changed, 47 insertions, 40 deletions

diff --git a/Applications/FileManager/DirectoryView.cpp b/Applications/FileManager/DirectoryView.cpp
index 90485803e5..4a596ed92a 100644
--- a/Applications/FileManager/DirectoryView.cpp
+++ b/Applications/FileManager/DirectoryView.cpp
@@ -93,7 +93,7 @@ void DirectoryView::handle_activation(const GUI::ModelIndex& index)
         return;
     dbgprintf("on activation: %d,%d, this=%p, m_model=%p\n", index.row(), index.column(), this, m_model.ptr());
     auto& node = model().node(index);
-    auto path = node.full_path(model());
+    auto path = node.full_path();
 
     struct stat st;
     if (stat(path.characters(), &st) < 0) {
diff --git a/Applications/FileManager/main.cpp b/Applications/FileManager/main.cpp
index 4cc6db450e..f6272e1042 100644
--- a/Applications/FileManager/main.cpp
+++ b/Applications/FileManager/main.cpp
@@ -705,11 +705,11 @@ int run_in_windowed_mode(RefPtr<Core::ConfigFile> config, String initial_locatio
             auto& node = directory_view.model().node(index);
 
             if (node.is_directory()) {
-                auto should_get_enabled = access(node.full_path(directory_view.model()).characters(), W_OK) == 0 && GUI::Clipboard::the().type() == "text/uri-list";
+                auto should_get_enabled = access(node.full_path().characters(), W_OK) == 0 && GUI::Clipboard::the().type() == "text/uri-list";
                 folder_specific_paste_action->set_enabled(should_get_enabled);
                 directory_context_menu->popup(event.screen_position());
             } else {
-                auto full_path = node.full_path(directory_view.model());
+                auto full_path = node.full_path();
                 current_file_handlers = directory_view.get_launch_handlers(full_path);
 
                 file_context_menu = GUI::Menu::construct("Directory View File");
@@ -774,10 +774,10 @@ int run_in_windowed_mode(RefPtr<Core::ConfigFile> config, String initial_locatio
             return;
 
         for (auto& url_to_copy : urls) {
-            if (!url_to_copy.is_valid() || url_to_copy.path() == target_node.full_path(directory_view.model()))
+            if (!url_to_copy.is_valid() || url_to_copy.path() == target_node.full_path())
                 continue;
             auto new_path = String::format("%s/%s",
-                target_node.full_path(directory_view.model()).characters(),
+                target_node.full_path().characters(),
                 LexicalPath(url_to_copy.path()).basename().characters());
 
             if (url_to_copy.path() == new_path)
diff --git a/Libraries/LibGUI/FilePicker.cpp b/Libraries/LibGUI/FilePicker.cpp
index b2bbf4399d..3c3a03132c 100644
--- a/Libraries/LibGUI/FilePicker.cpp
+++ b/Libraries/LibGUI/FilePicker.cpp
@@ -202,7 +202,7 @@ FilePicker::FilePicker(Window* parent_window, Mode mode, Options options, const
         auto& filter_model = (SortingProxyModel&)*m_view->model();
         auto local_index = filter_model.map_to_source(index);
         const FileSystemModel::Node& node = m_model->node(local_index);
-        LexicalPath path { node.full_path(m_model) };
+        LexicalPath path { node.full_path() };
 
         if (have_preview())
             clear_preview();
@@ -240,7 +240,7 @@ FilePicker::FilePicker(Window* parent_window, Mode mode, Options options, const
         auto& filter_model = (SortingProxyModel&)*m_view->model();
         auto local_index = filter_model.map_to_source(index);
         const FileSystemModel::Node& node = m_model->node(local_index);
-        auto path = node.full_path(m_model);
+        auto path = node.full_path();
 
         if (node.is_directory()) {
             set_path(path);
diff --git a/Libraries/LibGUI/FileSystemModel.cpp b/Libraries/LibGUI/FileSystemModel.cpp
index 8c5035a760..6e5d11eab6 100644
--- a/Libraries/LibGUI/FileSystemModel.cpp
+++ b/Libraries/LibGUI/FileSystemModel.cpp
@@ -44,13 +44,13 @@
 
 namespace GUI {
 
-ModelIndex FileSystemModel::Node::index(const FileSystemModel& model, int column) const
+ModelIndex FileSystemModel::Node::index(int column) const
 {
     if (!parent)
         return {};
     for (size_t row = 0; row < parent->children.size(); ++row) {
         if (&parent->children[row] == this)
-            return model.create_index(row, column, const_cast<Node*>(this));
+            return m_model.create_index(row, column, const_cast<Node*>(this));
     }
     ASSERT_NOT_REACHED();
 }
@@ -85,15 +85,15 @@ bool FileSystemModel::Node::fetch_data(const String& full_path, bool is_root)
     return true;
 }
 
-void FileSystemModel::Node::traverse_if_needed(const FileSystemModel& model)
+void FileSystemModel::Node::traverse_if_needed()
 {
     if (!is_directory() || has_traversed)
         return;
     has_traversed = true;
     total_size = 0;
 
-    auto full_path = this->full_path(model);
-    Core::DirIterator di(full_path, model.should_show_dotfiles() ? Core::DirIterator::SkipParentAndBaseDir : Core::DirIterator::SkipDots);
+    auto full_path = this->full_path();
+    Core::DirIterator di(full_path, m_model.should_show_dotfiles() ? Core::DirIterator::SkipParentAndBaseDir : Core::DirIterator::SkipDots);
     if (di.has_error()) {
         m_error = di.error();
         fprintf(stderr, "DirIterator: %s\n", di.error_string());
@@ -108,11 +108,11 @@ void FileSystemModel::Node::traverse_if_needed(const FileSystemModel& model)
 
     for (auto& name : child_names) {
         String child_path = String::format("%s/%s", full_path.characters(), name.characters());
-        NonnullOwnPtr<Node> child = make<Node>();
+        auto child = adopt_own(*new Node(m_model));
         bool ok = child->fetch_data(child_path, false);
         if (!ok)
             continue;
-        if (model.m_mode == DirectoriesOnly && !S_ISDIR(child->mode))
+        if (m_model.m_mode == DirectoriesOnly && !S_ISDIR(child->mode))
             continue;
         child->name = name;
         child->parent = this;
@@ -131,7 +131,7 @@ void FileSystemModel::Node::traverse_if_needed(const FileSystemModel& model)
     fcntl(m_watch_fd, F_SETFD, FD_CLOEXEC);
     dbg() << "Watching " << full_path << " for changes, m_watch_fd = " << m_watch_fd;
     m_notifier = Core::Notifier::construct(m_watch_fd, Core::Notifier::Event::Read);
-    m_notifier->on_ready_to_read = [this, &model] {
+    m_notifier->on_ready_to_read = [this] {
         char buffer[32];
         int rc = read(m_notifier->fd(), buffer, sizeof(buffer));
         ASSERT(rc >= 0);
@@ -139,27 +139,27 @@ void FileSystemModel::Node::traverse_if_needed(const FileSystemModel& model)
         has_traversed = false;
         mode = 0;
         children.clear();
-        reify_if_needed(model);
-        const_cast<FileSystemModel&>(model).did_update();
+        reify_if_needed();
+        m_model.did_update();
     };
 }
 
-void FileSystemModel::Node::reify_if_needed(const FileSystemModel& model)
+void FileSystemModel::Node::reify_if_needed()
 {
-    traverse_if_needed(model);
+    traverse_if_needed();
     if (mode != 0)
         return;
-    fetch_data(full_path(model), parent == nullptr);
+    fetch_data(full_path(), parent == nullptr);
 }
 
-String FileSystemModel::Node::full_path(const FileSystemModel& model) const
+String FileSystemModel::Node::full_path() const
 {
     Vector<String, 32> lineage;
     for (auto* ancestor = parent; ancestor; ancestor = ancestor->parent) {
         lineage.append(ancestor->name);
     }
     StringBuilder builder;
-    builder.append(model.root_path());
+    builder.append(m_model.root_path());
     for (int i = lineage.size() - 1; i >= 0; --i) {
         builder.append('/');
         builder.append(lineage[i]);
@@ -174,17 +174,17 @@ ModelIndex FileSystemModel::index(const StringView& path, int column) const
     LexicalPath lexical_path(path);
     const Node* node = m_root;
     if (lexical_path.string() == "/")
-        return m_root->index(*this, column);
+        return m_root->index(column);
     for (size_t i = 0; i < lexical_path.parts().size(); ++i) {
         auto& part = lexical_path.parts()[i];
         bool found = false;
         for (auto& child : node->children) {
             if (child.name == part) {
-                const_cast<Node&>(child).reify_if_needed(*this);
+                const_cast<Node&>(child).reify_if_needed();
                 node = &child;
                 found = true;
                 if (i == lexical_path.parts().size() - 1)
-                    return child.index(*this, column);
+                    return child.index(column);
                 break;
             }
         }
@@ -197,8 +197,8 @@ ModelIndex FileSystemModel::index(const StringView& path, int column) const
 String FileSystemModel::full_path(const ModelIndex& index) const
 {
     auto& node = this->node(index);
-    const_cast<Node&>(node).reify_if_needed(*this);
-    return node.full_path(*this);
+    const_cast<Node&>(node).reify_if_needed();
+    return node.full_path();
 }
 
 FileSystemModel::FileSystemModel(const StringView& root_path, Mode mode)
@@ -303,8 +303,8 @@ void FileSystemModel::set_root_path(const StringView& root_path)
 
 void FileSystemModel::update()
 {
-    m_root = make<Node>();
-    m_root->reify_if_needed(*this);
+    m_root = adopt_own(*new Node(*this));
+    m_root->reify_if_needed();
 
     did_update();
 }
@@ -312,7 +312,7 @@ void FileSystemModel::update()
 int FileSystemModel::row_count(const ModelIndex& index) const
 {
     Node& node = const_cast<Node&>(this->node(index));
-    node.reify_if_needed(*this);
+    node.reify_if_needed();
     if (node.is_directory())
         return node.children.size();
     return 0;
@@ -331,7 +331,7 @@ ModelIndex FileSystemModel::index(int row, int column, const ModelIndex& parent)
     if (row < 0 || column < 0)
         return {};
     auto& node = this->node(parent);
-    const_cast<Node&>(node).reify_if_needed(*this);
+    const_cast<Node&>(node).reify_if_needed();
     if (static_cast<size_t>(row) >= node.children.size())
         return {};
     return create_index(row, column, &node.children[row]);
@@ -346,7 +346,7 @@ ModelIndex FileSystemModel::parent_index(const ModelIndex& index) const
         ASSERT(&node == m_root);
         return {};
     }
-    return node.parent->index(*this, index.column());
+    return node.parent->index(index.column());
 }
 
 Variant FileSystemModel::data(const ModelIndex& index, ModelRole role) const
@@ -377,14 +377,14 @@ Variant FileSystemModel::data(const ModelIndex& index, ModelRole role) const
     if (role == ModelRole::Custom) {
         // For GUI::FileSystemModel, custom role means the full path.
         ASSERT(index.column() == Column::Name);
-        return node.full_path(*this);
+        return node.full_path();
     }
 
     if (role == ModelRole::DragData) {
         if (index.column() == Column::Name) {
             StringBuilder builder;
             builder.append("file://");
-            builder.append(node.full_path(*this));
+            builder.append(node.full_path());
             return builder.to_string();
         }
         return {};
@@ -454,7 +454,7 @@ Icon FileSystemModel::icon_for(const Node& node) const
     }
 
     if (node.is_directory()) {
-        if (node.full_path(*this) == Core::StandardPaths::home_directory()) {
+        if (node.full_path() == Core::StandardPaths::home_directory()) {
             if (node.is_selected())
                 return FileIconProvider::home_directory_open_icon();
             return FileIconProvider::home_directory_icon();
@@ -489,7 +489,7 @@ bool FileSystemModel::fetch_thumbnail_for(const Node& node)
 {
     // See if we already have the thumbnail
     // we're looking for in the cache.
-    auto path = node.full_path(*this);
+    auto path = node.full_path();
     auto it = s_thumbnail_cache.find(path);
     if (it != s_thumbnail_cache.end()) {
         if (!(*it).value)
diff --git a/Libraries/LibGUI/FileSystemModel.h b/Libraries/LibGUI/FileSystemModel.h
index c09bea5012..7948f128d0 100644
--- a/Libraries/LibGUI/FileSystemModel.h
+++ b/Libraries/LibGUI/FileSystemModel.h
@@ -87,11 +87,18 @@ public:
         int error() const { return m_error; }
         const char* error_string() const { return strerror(m_error); }
 
-        String full_path(const FileSystemModel&) const;
+        String full_path() const;
 
     private:
         friend class FileSystemModel;
 
+        explicit Node(FileSystemModel& model)
+            : m_model(model)
+        {
+        }
+
+        FileSystemModel& m_model;
+
         Node* parent { nullptr };
         NonnullOwnPtrVector<Node> children;
         bool has_traversed { false };
@@ -103,9 +110,9 @@ public:
 
         int m_error { 0 };
 
-        ModelIndex index(const FileSystemModel&, int column) const;
-        void traverse_if_needed(const FileSystemModel&);
-        void reify_if_needed(const FileSystemModel&);
+        ModelIndex index(int column) const;
+        void traverse_if_needed();
+        void reify_if_needed();
         bool fetch_data(const String& full_path, bool is_root);
     };