[Sketcher] Add tests for split and trim

Includes:
* Tests for splitting and trimming of various types of curves
* Assertions on constraints expected to be added on these curves

src/Mod/Sketcher/App/SketchObject.cpp

@@ -6967,6 +6967,39 @@ int SketchObject::deleteUnusedInternalGeometry(int GeoId, bool delgeoid)
     }
 }
 
+int SketchObject::deleteUnusedInternalGeometryAndUpdateGeoId(int& GeoId, bool delgeoid)
+{
+    const Part::Geometry* geo = getGeometry(GeoId);
+
+    if (!hasInternalGeometry(geo)) {
+        return -1;
+    }
+    // We need to remove the internal geometry of the BSpline, as BSplines change in number
+    // of poles and knots We save the tags of the relevant geometry to retrieve the new
+    // GeoIds later on.
+    boost::uuids::uuid GeoIdTag;
+
+    GeoIdTag = geo->getTag();
+
+    int returnValue = deleteUnusedInternalGeometry(GeoId, delgeoid);
+
+    if (delgeoid) {
+        GeoId = GeoEnum::GeoUndef;
+        return returnValue;
+    }
+
+    auto vals = getCompleteGeometry();
+
+    for (size_t i = 0; i < vals.size(); i++) {
+        if (vals[i]->getTag() == GeoIdTag) {
+            GeoId = getGeoIdFromCompleteGeometryIndex(i);
+            break;
+        }
+    }
+
+    return returnValue;
+}
+
 bool SketchObject::convertToNURBS(int GeoId)
 {
     // no need to check input data validity as this is an sketchobject managed operation.

src/Mod/Sketcher/App/SketchObject.h

@@ -460,6 +460,14 @@ public:
      geometry \retval int - returns -1 on error, otherwise the number of deleted elements
      */
     int deleteUnusedInternalGeometry(int GeoId, bool delgeoid = false);
+    /*!
+     \brief Same as `deleteUnusedInternalGeometry`, but changes `GeoId` to the new Id of the
+     geometry, or to `GeoEnum::GeoUndef` if the geometry is deleted as well. \param GeoId - the
+     geometry having the internal geometry to delete \param delgeoid - if true in addition to the
+     unused internal geometry also deletes the GeoId geometry \retval int - returns -1 on error,
+     otherwise the number of deleted elements
+     */
+    int deleteUnusedInternalGeometryAndUpdateGeoId(int& GeoId, bool delgeoid = false);
     /*!
      \brief Approximates the given geometry with a B-spline
      \param GeoId - the geometry to approximate