Fix version manager

Tribler/Core/Upgrade/version_manager.py

@@ -68,15 +68,30 @@ def setup_state_directory_for_upgrade(self, version_id=None):
             return
 
         code_version = version_id or tribler_version.version_id
+        # To check if Tribler directory for the running version already exists, we must check for its *contents*
+        # because the directory itself is already created earlier
+        # FIXME: reposition upgrader so it will start *before* creating the state directory
+        code_version_directory_exists = (self.get_state_directory(code_version) / 'triblerd.conf').exists()
+
         last_usage_version = self.version_history.get("last_version", None)
-        code_version_directory_exists = self.get_state_directory(code_version).exists()
-        upgrade_possible = last_usage_version and LooseVersion(last_usage_version) < LooseVersion(code_version)
+        last_usage_version_directory_exists = self.get_state_directory(last_usage_version).exists()
+
+        upgrade_possible = False
+        # Pre-requisites for upgrading:
+        # the old directory should exist and the newer version should be higher then the old one
+        if last_usage_version_directory_exists and not code_version_directory_exists:
+            if last_usage_version is not None:
+                # Normal upgrade, e.g. 7.4.1->7.4.2
+                upgrade_possible = LooseVersion(last_usage_version) < LooseVersion(code_version)
+            else:
+                # Legacy upgrade
+                upgrade_possible = True
+
+        # If upgrade is possible, fork the state directory for the new code version
+        if upgrade_possible:
 
-        # If there is no state directory for the code version and
-        # the last used state directory versions is lower then the current version
-        # then fork the state directory for the new code version and update the history file.
-        if not code_version_directory_exists and upgrade_possible:
             self.fork_state_directory(code_version, self.get_state_directory(last_usage_version))
+        # Update the history file
         if last_usage_version != code_version:
             self.update_version_history(code_version)
 

Tribler/Test/Core/Upgrade/test_version_manager.py

@@ -1,6 +1,8 @@
 from __future__ import absolute_import
 
+import filecmp
 import os
+from pathlib import Path
 
 from configobj import ConfigObj
 
@@ -87,6 +89,14 @@ def test_setup_state_directory_for_upgrade(self):
         version_state_dir = self.version_manager.get_state_directory(current_version)
         self.assertTrue(os.path.exists(version_state_dir))
 
+
+        post_upgrade_state_dir = self.config.get_state_dir()
+        # Make sure the directories before and after upgrade are different
+        self.assertFalse(version_state_dir == post_upgrade_state_dir)
+        # Make sure the contents in the before and after upgrade directories are the same
+        self.assertTrue(filecmp.cmp(Path(version_state_dir)/'ec_multichain.pem',
+                                    Path(post_upgrade_state_dir)/'ec_multichain.pem'))
+
         version_state_sub_dirs = os.listdir(version_state_dir)
         backup_dirs = [STATEDIR_DB_DIR, STATEDIR_CHECKPOINT_DIR, STATEDIR_WALLET_DIR, STATEDIR_CHANNELS_DIR]
         for backup_dir in backup_dirs: