Simplify is_valid_directory and is_valid_textfile

Author: Jeremy Wootten

src/FolderManager/File.vala

@@ -83,31 +83,29 @@ namespace Scratch.FolderManager {
         }
 
         // Checks if we're dealing with a non-backup directory
-        // Hidden subfolders are not shown by default, but we need to allow hidden top-level folder
-        public bool is_valid_directory (bool allow_hidden = true) {
-            if ((!allow_hidden && name.has_prefix (".")) || // If parent is hidden then inherit validity from parent
-                 info.get_is_backup ()) {
-
-                return false;
-            }
+        // If parent is hidden then inherit validity from parent
+        private bool? _is_valid_directory = null;
+        public bool is_valid_directory {
+            get {
+                if (_is_valid_directory == null) {
+                _is_valid_directory = info != null &&
+                                      !info.get_is_backup () &&
+                                      info.get_file_type () == FileType.DIRECTORY;
+                }
 
-            if (info.get_file_type () == FileType.DIRECTORY) {
-                return true;
+                return _is_valid_directory;
             }
-
-            return false;
         }
 
-        public bool is_temporary {
-            get {
-               return path.has_suffix ("~");
-            }
-         }
-
         // checks if we're dealing with a textfile
+        private bool? _is_valid_textfile = null;
         public bool is_valid_textfile {
             get {
-                return Utils.check_if_valid_text_file (path, info);
+                if (_is_valid_textfile == null) {
+                    _is_valid_textfile = !path.has_suffix ("~") && Utils.check_if_valid_text_file (path, info);
+                }
+
+                return _is_valid_textfile;
             }
         }
 
@@ -143,7 +141,7 @@ namespace Scratch.FolderManager {
                     while ((file_info = enumerator.next_file ()) != null) {
                         var child = file.get_child (file_info.get_name ());
                         var child_file = new File (child.get_path ());
-                        if (child_file.is_valid_directory () || child_file.is_valid_textfile) {
+                        if (child_file.is_valid_directory || child_file.is_valid_textfile) {
                             _children.add (child_file);
                         }
                     }
@@ -200,10 +198,10 @@ namespace Scratch.FolderManager {
         }
 
         public static int compare (File a, File b) {
-            if (a.is_valid_directory () && b.is_valid_textfile) {
+            if (a.is_valid_directory && b.is_valid_textfile) {
                 return -1;
             }
-            if (a.is_valid_textfile && b.is_valid_directory ()) {
+            if (a.is_valid_textfile && b.is_valid_directory) {
                 return 1;
             }
 

src/FolderManager/FileView.vala

@@ -509,7 +509,7 @@ public class Scratch.FolderManager.FileView : Code.Widgets.SourceList, Code.Pane
         if (is_open (folder)) {
             warning ("Folder '%s' is already open.", folder.path);
             return;
-        } else if (!folder.is_valid_directory (true)) { // Allow hidden top-level folders
+        } else if (!folder.is_valid_directory) {
             warning ("Cannot open invalid directory.");
             return;
         }

src/FolderManager/FolderItem.vala

@@ -29,7 +29,7 @@ namespace Scratch.FolderManager {
         private bool has_dummy;
         private Code.Widgets.SourceList.Item dummy; /* Blank item for expanded empty folders */
 
-        public FolderItem (File file, FileView view) requires (file.is_valid_directory) {
+        public FolderItem (File file, FileView view) {
             Object (file: file, view: view);
         }
 
@@ -63,16 +63,14 @@ namespace Scratch.FolderManager {
                  file.children.size > 0) {
 
                 foreach (var child in file.children) {
-                    Code.Widgets.SourceList.Item item = null;
-                    if (child.is_valid_directory ()) {
+                    Code.Widgets.SourceList.Item? item = null;
+                    if (child.is_valid_directory) {
                         item = new FolderItem (child, view);
                     } else if (child.is_valid_textfile) {
                         item = new FileItem (child, view);
                     }
 
-                    if (item != null) {
-                        add (item);
-                    }
+                    add (item); // ignores null parameter
                 }
 
                 children_loaded = true;
@@ -304,15 +302,14 @@ namespace Scratch.FolderManager {
                         var path_item = find_item_for_path (source.get_path ());
                         if (path_item == null) {
                             var file = new File (source.get_path ());
-                            if (file.is_valid_directory ()) {
+                            if (file.is_valid_directory) {
                                 path_item = new FolderItem (file, view);
-                            } else if (!file.is_temporary) {
+
+                            } else if (file.is_valid_textfile) {
                                 path_item = new FileItem (file, view);
-                            } else {
-                                break;
                             }
 
-                            add (path_item);
+                            add (path_item); // null parameter is silently ignored
                         }
 
                         break;