- fix crashes on 0 args

Author: fbergmann

src/sbml/math/ASTNode.cpp

@@ -3900,7 +3900,7 @@ ASTNode::simplify()
   }
 
   // if we have 1 * x * ... dont need 1
-  if (mType == AST_TIMES && util_isEqual(getChild(0)->getValue(), 1.0))
+  if (mType == AST_TIMES && numChildren > 0 && util_isEqual(getChild(0)->getValue(), 1.0))
   {
     ASTNode * newNode = new ASTNode(AST_TIMES);
     for (unsigned int i = 1; i < numChildren; ++i)
@@ -3913,7 +3913,7 @@ ASTNode::simplify()
   }
 
   // if we have A - A should be 0
-  if (mType == AST_MINUS && getChild(0)->exactlyEqual(*getChild(1)))
+  if (mType == AST_MINUS && numChildren > 0 && getChild(0)->exactlyEqual(*getChild(1)))
   {
       ASTNode* child = zero->deepCopy();
       (*this) = *(child);
@@ -3924,7 +3924,7 @@ ASTNode::simplify()
   // or n + a + a should get n + 2*a
   // or n + a + b + b should get n + a + 2*b
 
-  if (mType == AST_PLUS)
+  if (mType == AST_PLUS && numChildren > 0)
   {
     bool match = false;
     unsigned int i;
@@ -3948,21 +3948,21 @@ ASTNode::simplify()
     }
   }
   // if we have A/A should be 1
-  if (mType == AST_DIVIDE && getChild(0)->exactlyEqual(*getChild(1)))
+  if (mType == AST_DIVIDE && numChildren > 1  && getChild(0)->exactlyEqual(*getChild(1)))
   {
     ASTNode* child = one->deepCopy();
     (*this) = *(child);
     delete child;
   }
   // if we have A^1 just have A
-  if ((mType == AST_POWER || mType == AST_FUNCTION_POWER) && getChild(1)->exactlyEqual(*one))
+  if ((mType == AST_POWER || mType == AST_FUNCTION_POWER) && numChildren > 1 && getChild(1)->exactlyEqual(*one))
   {
     ASTNode* child = getChild(0)->deepCopy();
     (*this) = *(child);
     delete child;
   }
   // if we have A^0 just have 1
-  if ((mType == AST_POWER || mType == AST_FUNCTION_POWER) && getChild(1)->exactlyEqual(*zero))
+  if ((mType == AST_POWER || mType == AST_FUNCTION_POWER) && numChildren > 1 && getChild(1)->exactlyEqual(*zero))
   {
     ASTNode* child = one->deepCopy();
     (*this) = *(child);
@@ -4190,7 +4190,7 @@ ASTNode::decompose()
       }
     }
   }
-  else if (getType() == AST_DIVIDE)
+  else if (getType() == AST_DIVIDE && getNumChildren() > 0)
   {
     type = getChild(0)->getType();
     if (type == AST_PLUS || type == AST_MINUS)

src/sbml/math/test/TestDerivativeFunctions.cpp

@@ -79,7 +79,7 @@ equals(const char* expected, const char* actual)
 static bool
 formulas_equal(const char* expected, ASTNode* actual)
 {
-	return equals(expected, SBML_formulaToL3String(actual));
+  return equals(expected, SBML_formulaToL3String(actual));
 }
 
 START_TEST (test_deriv_const)
@@ -174,6 +174,20 @@ START_TEST(test_deriv_plus)
   delete n;
   delete node;
   delete deriv;
+
+  // test 0 args:
+  n = readMathMLFromString(
+    "<math xmlns='http://www.w3.org/1998/Math/MathML'>"
+    "  <apply>"
+    "    <plus/>"
+    "  </apply>"
+    "</math>"
+  );
+
+  deriv = n->derivative(x);
+
+  delete n;
+  delete deriv;
 }
 END_TEST
 
@@ -299,6 +313,25 @@ START_TEST(test_deriv_times)
   delete n;
   delete node;
   delete deriv;
+
+  // also check that it does not crash on no args:
+  n = readMathMLFromString(
+    "<math xmlns='http://www.w3.org/1998/Math/MathML'>"
+    "  <apply>"
+    "    <times/>"
+    "  </apply>"
+    "</math>"
+  );
+
+  deriv = n->derivative(x);
+
+  // should be 0
+  fail_unless(deriv->isNumber() == true);
+  fail_unless(deriv->getValue() == 0.0);
+
+  delete n;
+  delete deriv;
+
 }
 END_TEST
 
@@ -361,6 +394,19 @@ START_TEST(test_deriv_divide)
   delete n;
   delete node;
   delete deriv;
+
+  // test 0 args: 
+  n = readMathMLFromString(
+    "<math xmlns='http://www.w3.org/1998/Math/MathML'>"
+    "  <apply>"
+    "    <divide/>"
+    "  </apply>"
+    "</math>"
+  );
+  deriv = n->derivative(x);
+
+  delete n;
+  delete deriv;
 }
 END_TEST
 
@@ -484,6 +530,23 @@ START_TEST(test_deriv_minus)
   delete n;
   delete node;
   delete deriv;
+
+
+  // test 0 args
+  n = readMathMLFromString(
+    "<math xmlns='http://www.w3.org/1998/Math/MathML'>"
+    "  <apply>"
+    "    <minus/>"
+    "  </apply>"
+    "</math>"
+  );
+
+  deriv = n->derivative(x);
+
+  delete n;
+  delete deriv;
+
+
 }
 END_TEST
 
@@ -613,6 +676,19 @@ START_TEST(test_deriv_power)
   delete n;
   delete node;
   delete deriv;
+
+  // test 0 arg
+  n = readMathMLFromString(
+    "<math xmlns='http://www.w3.org/1998/Math/MathML'>"
+    "  <apply>"
+    "    <power/>"
+    "  </apply>"
+    "</math>"
+  );
+
+  deriv = n->derivative(x);
+  delete n;
+  delete deriv;
 }
 END_TEST
 
@@ -810,6 +886,19 @@ START_TEST(test_deriv_log)
   delete n;
   delete node;
   delete deriv;
+
+  // test 0 args:
+  n = readMathMLFromString(
+    "<math xmlns='http://www.w3.org/1998/Math/MathML'>"
+    "  <apply>"
+    "    <log/>"
+    "  </apply>"
+    "</math>");
+
+  deriv = n->derivative(x);
+
+  delete n;
+  delete deriv;
 }
 END_TEST
 
@@ -957,6 +1046,20 @@ START_TEST(test_deriv_exp)
   delete n;
   delete node;
   delete deriv;
+
+  // test 0 args:
+  n = readMathMLFromString(
+    "<math xmlns='http://www.w3.org/1998/Math/MathML'>"
+    "  <apply>"
+    "    <exp/>"
+    "  </apply>"
+    "</math>"
+  );
+
+  deriv = n->derivative(x);
+
+  delete n;
+  delete deriv;
 }
 END_TEST
 
@@ -1016,6 +1119,20 @@ START_TEST(test_deriv_abs)
     delete n;
     delete node;
     delete deriv;
+
+    // test 0 args
+    n = readMathMLFromString(
+      "<math xmlns='http://www.w3.org/1998/Math/MathML'>"
+      "  <apply>"
+      "    <abs/>"
+      "  </apply>"
+      "</math>"
+    );
+
+    deriv = n->derivative(x);
+
+    delete n;
+    delete deriv;
 }
 END_TEST