From ee0bcc095c42c2b4bf07b91fb59c988e46c33bcf Mon Sep 17 00:00:00 2001
From: wandererfan <wandererfan@gmail.com>
Date: Sun, 8 Sep 2019 15:56:38 -0400
Subject: [PATCH] [TD]Check first/last geom points exist

---
 src/Mod/TechDraw/App/Geometry.cpp | 30 ++++++++++++++++++++++++------
 1 file changed, 24 insertions(+), 6 deletions(-)

diff --git a/src/Mod/TechDraw/App/Geometry.cpp b/src/Mod/TechDraw/App/Geometry.cpp
index d34eeb9bbf..bf5cde8abf 100644
--- a/src/Mod/TechDraw/App/Geometry.cpp
+++ b/src/Mod/TechDraw/App/Geometry.cpp
@@ -227,11 +227,15 @@ std::vector<Base::Vector3d> BaseGeom::findEndPoints()
 {
     std::vector<Base::Vector3d> result;
 
-    gp_Pnt p = BRep_Tool::Pnt(TopExp::FirstVertex(occEdge));
-    result.push_back(Base::Vector3d(p.X(),p.Y(), p.Z()));
-    p = BRep_Tool::Pnt(TopExp::LastVertex(occEdge));
-    result.push_back(Base::Vector3d(p.X(),p.Y(), p.Z()));
-
+    if (!occEdge.IsNull()) {
+        gp_Pnt p = BRep_Tool::Pnt(TopExp::FirstVertex(occEdge));
+        result.push_back(Base::Vector3d(p.X(),p.Y(), p.Z()));
+        p = BRep_Tool::Pnt(TopExp::LastVertex(occEdge));
+        result.push_back(Base::Vector3d(p.X(),p.Y(), p.Z()));
+    } else {
+        //TODO: this should throw something
+        Base::Console().Message("Geometry::findEndPoints - OCC edge not found\n");
+    }
     return result;
 }
 
@@ -239,13 +243,27 @@ std::vector<Base::Vector3d> BaseGeom::findEndPoints()
 Base::Vector3d BaseGeom::getStartPoint()
 {
     std::vector<Base::Vector3d> verts = findEndPoints();
-    return verts[0];
+    if (!verts.empty()) {
+        return verts[0];
+    } else {
+        //TODO: this should throw something
+        Base::Console().Message("Geometry::getStartPoint - start point not found!\n");
+        Base::Vector3d badResult(0.0, 0.0, 0.0);
+        return badResult;
+    }
 }
 
 
 Base::Vector3d BaseGeom::getEndPoint()
 {
     std::vector<Base::Vector3d> verts = findEndPoints();
+
+    if (verts.size() != 2) {
+        //TODO: this should throw something
+        Base::Console().Message("Geometry::getEndPoint - end point not found!\n");
+        Base::Vector3d badResult(0.0, 0.0, 0.0);
+        return badResult;
+    }
     return verts[1];
 }