Implement query for dependence on operator precedence

Author: rvermeulen

cpp/autosar/src/rules/M5-0-2/InsufficientUseOfParentheses.ql

@@ -17,7 +17,21 @@
 import cpp
 import codingstandards.cpp.autosar
 
-from Expr e
-where
-  not isExcluded(e, OrderOfEvaluationPackage::insufficientUseOfParenthesesQuery())
-select e, "Insufficient use of parenthesis in expression."
+class InsufficientlyParenthesizedExpr extends Expr {
+  InsufficientlyParenthesizedExpr() {
+    exists(BinaryOperation root, BinaryOperation child | child = this |
+      root.getAnOperand() = child and
+      root.getOperator() != child.getOperator() and
+      not any(ParenthesisExpr pe).getExpr() = child
+    )
+    or
+    exists(ConditionalExpr root, BinaryOperation child | child = this |
+      root.getAnOperand() = child and
+      not any(ParenthesisExpr pe).getExpr() = child
+    )
+  }
+}
+
+from InsufficientlyParenthesizedExpr e
+where not isExcluded(e, OrderOfEvaluationPackage::insufficientUseOfParenthesesQuery())
+select e, "Dependence on operator precedence rules."

cpp/autosar/test/rules/M5-0-2/InsufficientUseOfParentheses.expected

@@ -1 +1,8 @@
-No expected results have yet been specified
+| test.cpp:40:8:40:13 | ... * ... | Dependence on operator precedence rules. |
+| test.cpp:41:19:41:24 | ... * ... | Dependence on operator precedence rules. |
+| test.cpp:42:8:42:13 | ... * ... | Dependence on operator precedence rules. |
+| test.cpp:42:17:42:22 | ... * ... | Dependence on operator precedence rules. |
+| test.cpp:48:8:48:15 | ... == ... | Dependence on operator precedence rules. |
+| test.cpp:49:26:49:32 | ... - ... | Dependence on operator precedence rules. |
+| test.cpp:50:8:50:15 | ... == ... | Dependence on operator precedence rules. |
+| test.cpp:50:24:50:30 | ... - ... | Dependence on operator precedence rules. |

cpp/autosar/test/rules/M5-0-2/test.cpp

@@ -31,4 +31,21 @@ void f1() {
   int **l7;
   l1 = (*l7)[l2];           // NON_COMPLIANT[FALSE_NEGATIVE]
   char l8 = (char)(l1 + 1); // NON_COMPLIANT[FALSE_NEGATIVE]
+}
+
+void test_insufficient_parentheses() {
+  int l1, l2, l3;
+
+  l1 = (2 * l2) + (3 * l3);  // COMPLIANT
+  l1 = 2 * l2 + (3 * l3);    // NON_COMPLIANT
+  l1 = (2 * l2) + 3 * l3;    // NON_COMPLIANT
+  l1 = 2 * l2 + 3 * l3;      // NON_COMPLIANT
+  l1 = (2 * l2) + l3 + 1;    // COMPLIANT
+  l1 = (l2 + 1) - (l2 + l3); // COMPLIANT
+  l1 = l2 + l3 + 1;          // COMPLIANT
+
+  l1 = (l2 == l3) ? l2 : (l2 - l3); // COMPLIANT
+  l1 = l2 == l3 ? l2 : (l2 - l3);   // NON_COMPLIANT
+  l1 = (l2 == l3) ? l2 : l2 - l3;   // NON_COMPLIANT
+  l1 = l2 == l3 ? l2 : l2 - l3;     // NON_COMPLIANT
 }