Make version upgrade also translate file names

This was required since Cura 2.1 produced files with the same filename (bar extension). This then resulted in two containers with the same ID. If you had bad luck, an instance container was chosen as global container (depending on which was first in the unordered dictionary). This gives the current settings the postfix _current_settings, fixing that issue.

Contributes to issue CURA-844.

plugins/VersionUpgrade/VersionUpgrade21to22/MachineInstance.py

@@ -10,11 +10,12 @@ import io #To write config files to strings as if they were files.
 #   instance in version 1 of the file format.
 #
 #   \param serialised The serialised form of a machine instance in version 1.
+#   \param filename The supposed file name of this machine instance.
 #   \return A machine instance instance, or None if the file format is
 #   incorrect.
-def importFrom(serialised):
+def importFrom(serialised, filename):
     try:
-        return MachineInstance(serialised)
+        return MachineInstance(serialised, filename)
     except (configparser.Error, UM.VersionUpgrade.FormatException, UM.VersionUpgrade.InvalidVersionException):
         return None
 
@@ -24,7 +25,10 @@ class MachineInstance:
     ##  Reads version 1 of the file format, storing it in memory.
     #
     #   \param serialised A string with the contents of a machine instance file.
-    def __init__(self, serialised):
+    #   \param filename The supposed file name of this machine instance.
+    def __init__(self, serialised, filename):
+        self._filename = filename
+
         config = configparser.ConfigParser(interpolation = None)
         config.read_string(serialised) # Read the input string as config file.
 
@@ -55,8 +59,8 @@ class MachineInstance:
     #
     #   This is where the actual translation happens in this case.
     #
-    #   \return A serialised form of this machine instance, serialised in
-    #   version 2 of the file format.
+    #   \return A tuple containing the new filename and a serialised form of
+    #   this machine instance, serialised in version 2 of the file format.
     def export(self):
         config = configparser.ConfigParser(interpolation = None) # Build a config file in the form of version 2.
 
@@ -73,7 +77,7 @@ class MachineInstance:
         variant = VersionUpgrade21to22.VersionUpgrade21to22.VersionUpgrade21to22.translateVariant(self._variant_name, type_name)
 
         containers = [
-            self._name,
+            self._name + "_current_settings",
             active_profile,
             active_material,
             variant,
@@ -91,4 +95,4 @@ class MachineInstance:
 
         output = io.StringIO()
         config.write(output)
-        return output.getvalue()
+        return self._filename, output.getvalue()