From d7901907aff0709c65d0f79439e073c8d3983c8d Mon Sep 17 00:00:00 2001
From: Jaime van Kessel <nallath@gmail.com>
Date: Thu, 27 Sep 2018 15:37:08 +0200
Subject: [PATCH] Fix typing

---
 cura/PrinterOutput/ConfigurationModel.py | 16 ++++++++--------
 cura/Scene/ConvexHullDecorator.py        | 21 +++++++++++++--------
 2 files changed, 21 insertions(+), 16 deletions(-)

diff --git a/cura/PrinterOutput/ConfigurationModel.py b/cura/PrinterOutput/ConfigurationModel.py
index a3d6afd01d..b3e8373745 100644
--- a/cura/PrinterOutput/ConfigurationModel.py
+++ b/cura/PrinterOutput/ConfigurationModel.py
@@ -13,20 +13,20 @@ class ConfigurationModel(QObject):
 
     configurationChanged = pyqtSignal()
 
-    def __init__(self):
+    def __init__(self) -> None:
         super().__init__()
-        self._printer_type = None
+        self._printer_type = ""
         self._extruder_configurations = []     # type: List[ExtruderConfigurationModel]
-        self._buildplate_configuration = None
+        self._buildplate_configuration = ""
 
     def setPrinterType(self, printer_type):
         self._printer_type = printer_type
 
     @pyqtProperty(str, fset = setPrinterType, notify = configurationChanged)
-    def printerType(self):
+    def printerType(self) -> str:
         return self._printer_type
 
-    def setExtruderConfigurations(self, extruder_configurations):
+    def setExtruderConfigurations(self, extruder_configurations: List[ExtruderConfigurationModel]):
         if self._extruder_configurations != extruder_configurations:
             self._extruder_configurations = extruder_configurations
 
@@ -39,16 +39,16 @@ class ConfigurationModel(QObject):
     def extruderConfigurations(self):
         return self._extruder_configurations
 
-    def setBuildplateConfiguration(self, buildplate_configuration):
+    def setBuildplateConfiguration(self, buildplate_configuration: str) -> None:
         self._buildplate_configuration = buildplate_configuration
 
     @pyqtProperty(str, fset = setBuildplateConfiguration, notify = configurationChanged)
-    def buildplateConfiguration(self):
+    def buildplateConfiguration(self) -> str:
         return self._buildplate_configuration
 
     ##  This method is intended to indicate whether the configuration is valid or not.
     #   The method checks if the mandatory fields are or not set
-    def isValid(self):
+    def isValid(self) -> bool:
         if not self._extruder_configurations:
             return False
         for configuration in self._extruder_configurations:
diff --git a/cura/Scene/ConvexHullDecorator.py b/cura/Scene/ConvexHullDecorator.py
index a78f559aa1..31e21df6bf 100644
--- a/cura/Scene/ConvexHullDecorator.py
+++ b/cura/Scene/ConvexHullDecorator.py
@@ -78,7 +78,7 @@ class ConvexHullDecorator(SceneNodeDecorator):
 
         hull = self._compute2DConvexHull()
 
-        if self._global_stack and self._node:
+        if self._global_stack and self._node and hull is not None:
             # Parent can be None if node is just loaded.
             if self._global_stack.getProperty("print_sequence", "value") == "one_at_a_time" and (self._node.getParent() is None or not self._node.getParent().callDecoration("isGroup")):
                 hull = hull.getMinkowskiHull(Polygon(numpy.array(self._global_stack.getProperty("machine_head_polygon", "value"), numpy.float32)))
@@ -240,17 +240,22 @@ class ConvexHullDecorator(SceneNodeDecorator):
             return Polygon(numpy.array(self._global_stack.getHeadAndFansCoordinates(), numpy.float32))
         return Polygon()
 
-    def _compute2DConvexHeadFull(self) -> Polygon:
-        return self._compute2DConvexHull().getMinkowskiHull(self._getHeadAndFans())
+    def _compute2DConvexHeadFull(self) -> Optional[Polygon]:
+        convex_hull = self._compute2DConvexHeadFull()
+        if convex_hull:
+            return convex_hull.getMinkowskiHull(self._getHeadAndFans())
+        return None
 
-    def _compute2DConvexHeadMin(self) -> Polygon:
-        headAndFans = self._getHeadAndFans()
-        mirrored = headAndFans.mirror([0, 0], [0, 1]).mirror([0, 0], [1, 0])  # Mirror horizontally & vertically.
+    def _compute2DConvexHeadMin(self) -> Optional[Polygon]:
+        head_and_fans = self._getHeadAndFans()
+        mirrored = head_and_fans.mirror([0, 0], [0, 1]).mirror([0, 0], [1, 0])  # Mirror horizontally & vertically.
         head_and_fans = self._getHeadAndFans().intersectionConvexHulls(mirrored)
 
         # Min head hull is used for the push free
-        min_head_hull = self._compute2DConvexHull().getMinkowskiHull(head_and_fans)
-        return min_head_hull
+        convex_hull = self._compute2DConvexHeadFull()
+        if convex_hull:
+            return convex_hull.getMinkowskiHull(head_and_fans)
+        return None
 
     ##  Compensate given 2D polygon with adhesion margin
     #   \return 2D polygon with added margin