fix: allow for empty roots in configuration to properly display flat mailbox hierarchies

refs #9

Author: ThorstenSuckow

app/Conjoon/Mail/Client/Folder/Tree/DefaultMailFolderTreeBuilder.php

@@ -111,7 +111,7 @@ public function listToTree(MailFolderList $mailFolderList, array $root) :MailFol
                 $systemFolderTypes[] = $folderType;
             }
 
-            $parentKey = implode($mailbox->getDelimiter(), $parts);
+            $parentKey = implode($mailbox->getDelimiter(), $parts) ?: "*";
             if (!isset($folders[$parentKey])) {
                 $folders[$parentKey] = [];
             }
@@ -207,7 +207,7 @@ protected function shouldSkipMailFolder(ListMailFolder $listMailFolder, array $r
                 }
             }
         }
-        if ($skip === count($root)) {
+        if (count($root) && $skip === count($root)) {
             return true;
         }
 

tests/app/Conjoon/Mail/Client/Folder/Tree/DefaultMailFolderTreeBuilderTest.php

@@ -1,8 +1,8 @@
 <?php
 /**
  * conjoon
- * php-ms-imapuser
- * Copyright (C) 2019-2021 Thorsten Suckow-Homberg https://github.com/conjoon/php-ms-imapuser
+ * php-cn_imapuser
+ * Copyright (C) 2019 Thorsten Suckow-Homberg https://github.com/conjoon/php-cn_imapuser
  *
  * Permission is hereby granted, free of charge, to any person
  * obtaining a copy of this software and associated documentation
@@ -52,6 +52,38 @@ public function testInstance() {
     }
 
 
+    /**
+     * Tests listToTre
+     */
+    public function testListToTree_Entwürfe() {
+
+        $builder = $this->createBuilder();
+
+        $mailFolderList = $this->createMailFolderList(
+            ["Entwürfe",
+            "Gelöschte Elemente"]
+        );
+
+        $mailFolderChildList = $builder->listToTree($mailFolderList, [""]);
+
+        $this->assertSame(1, count($mailFolderChildList));
+
+        $mailFolder = $mailFolderChildList[0];
+        $this->assertSame("Entwürfe", $mailFolder->getName());
+        $this->assertSame("Entwürfe", $mailFolder->getFolderKey()->getId());
+        $this->assertSame(MailFolder::TYPE_DRAFT, $mailFolder->getFolderType());
+        $children = $mailFolder->getData();
+        $this->assertSame(0, count($children));
+
+        $drafts = $mailFolderChildList[1];
+        $this->assertSame("Gelöschte Elemente", $drafts->getName());
+        $this->assertSame("Gelöschte Elemente", $drafts->getFolderKey()->getId());
+        $this->assertSame(MailFolder::TYPE_TRASH, $drafts->getFolderType());
+        $children = $drafts->getData();
+        $this->assertSame(0, count($children));
+    }
+
+
     /**
      * Tests listToTre
      */