From afe8e70b86493fec9b6782c89883436a2c12e9b9 Mon Sep 17 00:00:00 2001
From: Florian Foinant-Willig <flachyjoe@gmail.com>
Date: Tue, 3 Oct 2023 21:40:49 +0200
Subject: [PATCH] Part: fix crash with null face

---
 src/Mod/Part/App/TopoShapeFacePyImp.cpp | 33 ++++++++++++++++---------
 1 file changed, 21 insertions(+), 12 deletions(-)

diff --git a/src/Mod/Part/App/TopoShapeFacePyImp.cpp b/src/Mod/Part/App/TopoShapeFacePyImp.cpp
index 378d919fe7..bf130e41cc 100644
--- a/src/Mod/Part/App/TopoShapeFacePyImp.cpp
+++ b/src/Mod/Part/App/TopoShapeFacePyImp.cpp
@@ -97,6 +97,15 @@ namespace Part {
     extern Py::Object shape2pyshape(const TopoDS_Shape &shape);
 }
 
+namespace{
+const TopoDS_Face& getTopoDSFace(const TopoShapeFacePy* theFace){
+    const TopoDS_Face& f = TopoDS::Face(theFace->getTopoShapePtr()->getShape());
+    if (f.IsNull())
+        throw Py::ValueError("Face is null");
+    return f;
+}
+}
+
 // returns a string which represent the object e.g. when printed in python
 std::string TopoShapeFacePy::representation() const
 {
@@ -414,7 +423,7 @@ PyObject* TopoShapeFacePy::makeOffset(PyObject *args)
     double dist;
     if (!PyArg_ParseTuple(args, "d",&dist))
         return nullptr;
-    const TopoDS_Face& f = TopoDS::Face(getTopoShapePtr()->getShape());
+    auto f = getTopoDSFace(this);
     BRepBuilderAPI_FindPlane findPlane(f);
     if (!findPlane.Found()) {
         PyErr_SetString(PartExceptionOCCError, "No planar face");
@@ -495,7 +504,7 @@ PyObject* TopoShapeFacePy::valueAt(PyObject *args)
     if (!PyArg_ParseTuple(args, "dd",&u,&v))
         return nullptr;
 
-    const TopoDS_Face& f = TopoDS::Face(getTopoShapePtr()->getShape());
+    auto f = getTopoDSFace(this);
 
     BRepAdaptor_Surface adapt(f);
     BRepLProp_SLProps prop(adapt,u,v,0,Precision::Confusion());
@@ -509,7 +518,7 @@ PyObject* TopoShapeFacePy::normalAt(PyObject *args)
     if (!PyArg_ParseTuple(args, "dd",&u,&v))
         return nullptr;
 
-    const TopoDS_Face& f = TopoDS::Face(getTopoShapePtr()->getShape());
+    auto f = getTopoDSFace(this);
     Standard_Boolean done;
     gp_Dir dir;
 
@@ -528,7 +537,7 @@ PyObject* TopoShapeFacePy::getUVNodes(PyObject *args)
     if (!PyArg_ParseTuple(args, ""))
         return nullptr;
 
-    const TopoDS_Face& f = TopoDS::Face(getTopoShapePtr()->getShape());
+    auto f = getTopoDSFace(this);
     TopLoc_Location aLoc;
     Handle (Poly_Triangulation) mesh = BRep_Tool::Triangulation(f,aLoc);
     if (mesh.IsNull()) {
@@ -571,7 +580,7 @@ PyObject* TopoShapeFacePy::tangentAt(PyObject *args)
 
     gp_Dir dir;
     Py::Tuple tuple(2);
-    const TopoDS_Face& f = TopoDS::Face(getTopoShapePtr()->getShape());
+    auto f = getTopoDSFace(this);
     BRepAdaptor_Surface adapt(f);
 
     BRepLProp_SLProps prop(adapt,u,v,2,Precision::Confusion());
@@ -602,7 +611,7 @@ PyObject* TopoShapeFacePy::curvatureAt(PyObject *args)
         return nullptr;
 
     Py::Tuple tuple(2);
-    const TopoDS_Face& f = TopoDS::Face(getTopoShapePtr()->getShape());
+    auto f = getTopoDSFace(this);
     BRepAdaptor_Surface adapt(f);
 
     BRepLProp_SLProps prop(adapt,u,v,2,Precision::Confusion());
@@ -625,7 +634,7 @@ PyObject* TopoShapeFacePy::derivative1At(PyObject *args)
         return nullptr;
 
     Py::Tuple tuple(2);
-    const TopoDS_Face& f = TopoDS::Face(getTopoShapePtr()->getShape());
+    auto f = getTopoDSFace(this);
     BRepAdaptor_Surface adapt(f);
 
     try {
@@ -649,7 +658,7 @@ PyObject* TopoShapeFacePy::derivative2At(PyObject *args)
         return nullptr;
 
     Py::Tuple tuple(2);
-    const TopoDS_Face& f = TopoDS::Face(getTopoShapePtr()->getShape());
+    auto f = getTopoDSFace(this);
     BRepAdaptor_Surface adapt(f);
 
     try {
@@ -849,7 +858,7 @@ PyObject* TopoShapeFacePy::cutHoles(PyObject *args)
             }
 
             if (!wires.empty()) {
-                const TopoDS_Face& f = TopoDS::Face(getTopoShapePtr()->getShape());
+                auto f = getTopoDSFace(this);
                 BRepBuilderAPI_MakeFace mkFace(f);
                 for (const auto & wire : wires)
                     mkFace.Add(wire);
@@ -1021,20 +1030,20 @@ Py::Object TopoShapeFacePy::getSurface() const
 
 Py::Float TopoShapeFacePy::getTolerance() const
 {
-    const TopoDS_Face& f = TopoDS::Face(getTopoShapePtr()->getShape());
+    auto f = getTopoDSFace(this);
     return Py::Float(BRep_Tool::Tolerance(f));
 }
 
 void TopoShapeFacePy::setTolerance(Py::Float tol)
 {
     BRep_Builder aBuilder;
-    const TopoDS_Face& f = TopoDS::Face(getTopoShapePtr()->getShape());
+    auto f = getTopoDSFace(this);
     aBuilder.UpdateFace(f, (double)tol);
 }
 
 Py::Tuple TopoShapeFacePy::getParameterRange() const
 {
-    const TopoDS_Face& f = TopoDS::Face(getTopoShapePtr()->getShape());
+    auto f = getTopoDSFace(this);
     BRepAdaptor_Surface adapt(f);
     double u1 = adapt.FirstUParameter();
     double u2 = adapt.LastUParameter();