Add VersionUpgrader for libArachne 5.0

Things to note:

* Since there is no VersionUpgrader from 4.8 to 4.9, this versionUpgrader attempts to upgrade
  files made in 4.8. This means that it touches files with setting_version = 16.
* The upgrade of the setting_version to 18 is currently commented out because we are not entirely
  sure that 18 will be the setting_version in 5.0.
* This versionUpgrader removes the following three settings that were removed in libArachne
	* "Compensate Wall Overlaps"
	* "Compensate Outer Wall Overlaps"
	* "Compensate Inner Wall Overlaps"
* The VersionUpgrader also disabled Fuzzy Skin from any profiles that may have it enabled, as fuzzy
  skin currently doesn't work in libArachne.
* The printer definitions have NOT been updated to the new setting_version to avoid having to deal
  with an enormous merge conflict in case the setting_version of 5.0 is something other than 18.
* Since the VersionUpgrader does not alter the setting_version, it will run every time Cura starts.

In short, this versionUpgrader runs and removes the deleted settings but it does not really change
the setting_version of any files.

Contributes to CURA-7683 and CURA-7656

plugins/VersionUpgrade/VersionUpgrade49to50/VersionUpgrade49to50.py

@@ -0,0 +1,98 @@
+# Copyright (c) 2020 Ultimaker B.V.
+# Cura is released under the terms of the LGPLv3 or higher.
+
+import configparser
+from typing import Tuple, List
+import io
+from UM.VersionUpgrade import VersionUpgrade
+
+_removed_settings = {
+    "travel_compensate_overlapping_walls_enabled",
+    "travel_compensate_overlapping_walls_0_enabled",
+    "travel_compensate_overlapping_walls_x_enabled"
+}
+
+
+class VersionUpgrade49to50(VersionUpgrade):
+    def upgradePreferences(self, serialized: str, filename: str) -> Tuple[List[str], List[str]]:
+        """
+        Upgrades preferences to remove from the visibility list the settings that were removed in this version.
+        It also changes the preferences to have the new version number.
+
+        This removes any settings that were removed in the new Cura version.
+        :param serialized: The original contents of the preferences file.
+        :param filename: The file name of the preferences file.
+        :return: A list of new file names, and a list of the new contents for
+        those files.
+        """
+        parser = configparser.ConfigParser(interpolation = None)
+        parser.read_string(serialized)
+
+        # Update version number. Disabled until we ensure that 18 will be the 5.0 setting version number
+        # parser["metadata"]["setting_version"] = "18"
+
+        # Remove deleted settings from the visible settings list.
+        if "general" in parser and "visible_settings" in parser["general"]:
+            visible_settings = set(parser["general"]["visible_settings"].split(";"))
+            for removed in _removed_settings:
+                if removed in visible_settings:
+                    visible_settings.remove(removed)
+            parser["general"]["visible_settings"] = ";".join(visible_settings)
+
+        result = io.StringIO()
+        parser.write(result)
+        return [filename], [result.getvalue()]
+
+    def upgradeInstanceContainer(self, serialized: str, filename: str) -> Tuple[List[str], List[str]]:
+        """
+        Upgrades instance containers to remove the settings that were removed in this version.
+        It also changes the instance containers to have the new version number.
+
+        This removes any settings that were removed in the new Cura version and updates settings that need to be updated
+        with a new value.
+
+        :param serialized: The original contents of the instance container.
+        :param filename: The original file name of the instance container.
+        :return: A list of new file names, and a list of the new contents for
+        those files.
+        """
+        parser = configparser.ConfigParser(interpolation = None, comment_prefixes = ())
+        parser.read_string(serialized)
+
+        # Update version number. Disabled until we ensure that 18 will be the 5.0 setting version number
+        # parser["metadata"]["setting_version"] = "18"
+
+        if "values" in parser:
+            # Remove deleted settings from the instance containers.
+            for removed in _removed_settings:
+                if removed in parser["values"]:
+                    del parser["values"][removed]
+
+            # Disable Fuzzy Skin as it doesn't work with with the libArachne walls
+            if "magic_fuzzy_skin_enabled" in parser["values"]:
+                parser["values"]["magic_fuzzy_skin_enabled"] = "False"
+
+        result = io.StringIO()
+        parser.write(result)
+        return [filename], [result.getvalue()]
+
+    def upgradeStack(self, serialized: str, filename: str) -> Tuple[List[str], List[str]]:
+        """
+        Upgrades stacks to have the new version number.
+
+        :param serialized: The original contents of the stack.
+        :param filename: The original file name of the stack.
+        :return: A list of new file names, and a list of the new contents for
+        those files.
+        """
+        parser = configparser.ConfigParser(interpolation = None)
+        parser.read_string(serialized)
+
+        # Update version number. Disabled until we ensure that 18 will be the 5.0 setting version number
+        if "metadata" not in parser:
+            parser["metadata"] = {}
+        # parser["metadata"]["setting_version"] = "18"
+
+        result = io.StringIO()
+        parser.write(result)
+        return [filename], [result.getvalue()]

plugins/VersionUpgrade/VersionUpgrade49to50/__init__.py

@@ -0,0 +1,67 @@
+# Copyright (c) 2020 Ultimaker B.V.
+# Cura is released under the terms of the LGPLv3 or higher.
+
+from typing import Any, Dict, TYPE_CHECKING
+
+from . import VersionUpgrade49to50
+
+if TYPE_CHECKING:
+    from UM.Application import Application
+
+upgrade = VersionUpgrade49to50.VersionUpgrade49to50()
+
+def getMetaData() -> Dict[str, Any]:
+    return {  # Since there is no VersionUpgrade from 48 to 49 yet, upgrade the 48 profiles to 50.
+        "version_upgrade": {
+            # From                           To                              Upgrade function
+            ("preferences", 6000016):        ("preferences", 6000018,        upgrade.upgradePreferences),
+            ("machine_stack", 4000016):      ("machine_stack", 4000018,      upgrade.upgradeStack),
+            ("extruder_train", 4000016):     ("extruder_train", 4000018,     upgrade.upgradeStack),
+            ("definition_changes", 4000016): ("definition_changes", 4000018, upgrade.upgradeInstanceContainer),
+            ("quality_changes", 4000016):    ("quality_changes", 4000018,    upgrade.upgradeInstanceContainer),
+            ("quality", 4000016):            ("quality", 4000018,            upgrade.upgradeInstanceContainer),
+            ("user", 4000016):               ("user", 4000018,               upgrade.upgradeInstanceContainer),
+
+            ("preferences", 6000016):        ("preferences", 6000018,        upgrade.upgradePreferences),
+            ("machine_stack", 4000016):      ("machine_stack", 4000018,      upgrade.upgradeStack),
+            ("extruder_train", 4000016):     ("extruder_train", 4000018,     upgrade.upgradeStack),
+            ("definition_changes", 4000016): ("definition_changes", 4000018, upgrade.upgradeInstanceContainer),
+            ("quality_changes", 4000016):    ("quality_changes", 4000018,    upgrade.upgradeInstanceContainer),
+            ("quality", 4000016):            ("quality", 4000018,            upgrade.upgradeInstanceContainer),
+            ("user", 4000016):               ("user", 4000018,               upgrade.upgradeInstanceContainer),
+        },
+        "sources": {
+            "preferences": {
+                "get_version": upgrade.getCfgVersion,
+                "location": {"."}
+            },
+            "machine_stack": {
+                "get_version": upgrade.getCfgVersion,
+                "location": {"./machine_instances"}
+            },
+            "extruder_train": {
+                "get_version": upgrade.getCfgVersion,
+                "location": {"./extruders"}
+            },
+            "definition_changes": {
+                "get_version": upgrade.getCfgVersion,
+                "location": {"./definition_changes"}
+            },
+            "quality_changes": {
+                "get_version": upgrade.getCfgVersion,
+                "location": {"./quality_changes"}
+            },
+            "quality": {
+                "get_version": upgrade.getCfgVersion,
+                "location": {"./quality"}
+            },
+            "user": {
+                "get_version": upgrade.getCfgVersion,
+                "location": {"./user"}
+            }
+        }
+    }
+
+
+def register(app: "Application") -> Dict[str, Any]:
+    return {"version_upgrade": upgrade}

plugins/VersionUpgrade/VersionUpgrade49to50/plugin.json

@@ -0,0 +1,8 @@
+{
+    "name": "Version Upgrade 4.9 to 5.0",
+    "author": "Ultimaker B.V.",
+    "version": "1.0.0",
+    "description": "Upgrades configurations from Cura 4.9 to Cura 5.0.",
+    "api": "7.4.0",
+    "i18n-catalog": "cura"
+}