[poincare] In rulegen, do not sort children of non-commutative nodes!!

Change-Id: Ibe228f400e688a17aeff4721fe6e77ab4bca1373

poincare/src/simplification/rulegen/node.cpp

@@ -186,6 +186,9 @@ void Node::sort() {
   for (Node * child : *m_children) {
     child->sort();
   }
+  if (!isCommutative()) {
+    return;
+  }
   for (int i = m_children->size()-1; i > 0; i--) {
     bool isSorted = true;
     for (int j = 0; j < m_children->size()-1; j++) {
@@ -200,6 +203,13 @@ void Node::sort() {
   }
 }
 
+bool Node::isCommutative() {
+  if (m_name->compare("Addition") == 0 || m_name->compare("Multiplication") == 0) {
+    return true;
+  }
+  return false;
+}
+
 #if 0
 
 std::string Node::generateSelectorConstructor(Rule * context) {

poincare/src/simplification/rulegen/node.h

@@ -30,7 +30,7 @@ public:
 private:
   int selectorCaptureIndexInRule(Rule * rule);
   int selectorIndexInRule(Rule * rule);
-
+  bool isCommutative();
   /*
   int generateTree(bool selector, Rule * context, int index, int indentationLevel);
   std::string generateSelectorConstructor(Rule * context);