From d4e8b95197c1e1a6cecfe0d5ff9765729bb02212 Mon Sep 17 00:00:00 2001
From: Abdullah Tahiri <abdullah.tahiri.yo@gmail.com>
Date: Sun, 17 Dec 2017 14:15:32 +0100
Subject: [PATCH] Sketcher: Support for detecting expressions in constraints

---
 src/Mod/Sketcher/App/SketchObject.cpp | 9 +++++++++
 src/Mod/Sketcher/App/SketchObject.h   | 2 ++
 2 files changed, 11 insertions(+)

diff --git a/src/Mod/Sketcher/App/SketchObject.cpp b/src/Mod/Sketcher/App/SketchObject.cpp
index dd65c3a281..bd8e4a7878 100644
--- a/src/Mod/Sketcher/App/SketchObject.cpp
+++ b/src/Mod/Sketcher/App/SketchObject.cpp
@@ -5839,6 +5839,15 @@ int SketchObject::changeConstraintsLocking(bool bLock)
     return cntSuccess;
 }
 
+bool SketchObject::constraintHasExpression(int constrid)
+{
+    App::ObjectIdentifier spath = this->Constraints.createPath(constrid);
+
+    App::PropertyExpressionEngine::ExpressionInfo expr_info = this->getExpression(spath);
+
+    return (expr_info.expression != 0);
+}
+
 
 /*!
  * \brief SketchObject::port_reversedExternalArcs finds constraints that link to endpoints of external-geometry arcs,
diff --git a/src/Mod/Sketcher/App/SketchObject.h b/src/Mod/Sketcher/App/SketchObject.h
index cb44ae4eb8..13ad9f4058 100644
--- a/src/Mod/Sketcher/App/SketchObject.h
+++ b/src/Mod/Sketcher/App/SketchObject.h
@@ -265,6 +265,8 @@ public:
     bool isPointOnCurve(int geoIdCurve, double px, double py);
     double calculateConstraintError(int ConstrId);
     int changeConstraintsLocking(bool bLock);
+    /// returns whether a given constraint has an associated expression or not
+    bool constraintHasExpression(int constrid);
 
     ///porting functions
     int port_reversedExternalArcs(bool justAnalyze);