A7-3-1: Exclude private member functions

Private member functions can't be inherited.

Author: lcartey

change_notes/2023-09-28-a7-3-1-updates.md

@@ -3,4 +3,5 @@
    - Reduce duplication when reporting the hidden function by reporting only one declaration entry.
    - Improve performance by eliminating a number of bad join orders.
    - Fix false positives where the using declaration occurred after the function declaration.
-   - Exclude special member functions, which cannot be inherited.
+   - Exclude special member functions, which cannot be inherited.
+   - Exclude private member functions, which cannot be inherited.

cpp/autosar/src/rules/A7-3-1/HiddenInheritedNonOverridableMemberFunction.ql

@@ -24,7 +24,9 @@ pragma[noinline, nomagic]
 predicate hasNonVirtualMemberFunction(Class clazz, MemberFunction mf, string name) {
   mf.getDeclaringType() = clazz and
   mf.getName() = name and
-  not mf.isVirtual()
+  not mf.isVirtual() and
+  // Exclude private member functions, which cannot be inherited.
+  not mf.isPrivate()
 }
 
 /**

cpp/autosar/src/rules/A7-3-1/HiddenInheritedOverridableMemberFunction.ql

@@ -21,6 +21,8 @@ where
   not isExcluded(overridingDecl, ScopePackage::hiddenInheritedOverridableMemberFunctionQuery()) and
   // Check if we are overriding a virtual inherited member function
   hiddenDecl.getDeclaration().isVirtual() and
+  // Exclude private member functions, which cannot be inherited.
+  not hiddenDecl.getDeclaration().(MemberFunction).isPrivate() and
   // The overriding declaration hides the hidden declaration if:
   (
     // 1. the overriding declaration overrides a function in a base class that is an overload of the hidden declaration

cpp/autosar/test/rules/A7-3-1/HiddenInheritedNonOverridableMemberFunction.expected

@@ -1 +1 @@
-| test.cpp:16:8:16:9 | f1 | Declaration for member 'f1' hides non-overridable inherited member function $@ | test.cpp:7:8:7:9 | f1 | f1 |
+| test.cpp:20:8:20:9 | f1 | Declaration for member 'f1' hides non-overridable inherited member function $@ | test.cpp:7:8:7:9 | f1 | f1 |

cpp/autosar/test/rules/A7-3-1/HiddenInheritedOverridableMemberFunction.expected

@@ -1,5 +1,5 @@
-| test.cpp:18:8:18:9 | declaration of f2 | Declaration for member 'f2' hides overridable inherited member function $@ | test.cpp:9:16:9:17 | declaration of f2 | f2 |
-| test.cpp:18:8:18:9 | declaration of f2 | Declaration for member 'f2' hides overridable inherited member function $@ | test.cpp:11:16:11:17 | declaration of f2 | f2 |
-| test.cpp:23:8:23:9 | declaration of f2 | Declaration for member 'f2' hides overridable inherited member function $@ | test.cpp:9:16:9:17 | declaration of f2 | f2 |
-| test.cpp:23:8:23:9 | declaration of f2 | Declaration for member 'f2' hides overridable inherited member function $@ | test.cpp:10:16:10:17 | declaration of f2 | f2 |
-| test.cpp:23:8:23:9 | declaration of f2 | Declaration for member 'f2' hides overridable inherited member function $@ | test.cpp:11:16:11:17 | declaration of f2 | f2 |
+| test.cpp:22:8:22:9 | declaration of f2 | Declaration for member 'f2' hides overridable inherited member function $@ | test.cpp:9:16:9:17 | declaration of f2 | f2 |
+| test.cpp:22:8:22:9 | declaration of f2 | Declaration for member 'f2' hides overridable inherited member function $@ | test.cpp:11:16:11:17 | declaration of f2 | f2 |
+| test.cpp:27:8:27:9 | declaration of f2 | Declaration for member 'f2' hides overridable inherited member function $@ | test.cpp:9:16:9:17 | declaration of f2 | f2 |
+| test.cpp:27:8:27:9 | declaration of f2 | Declaration for member 'f2' hides overridable inherited member function $@ | test.cpp:10:16:10:17 | declaration of f2 | f2 |
+| test.cpp:27:8:27:9 | declaration of f2 | Declaration for member 'f2' hides overridable inherited member function $@ | test.cpp:11:16:11:17 | declaration of f2 | f2 |

cpp/autosar/test/rules/A7-3-1/test.cpp

@@ -9,6 +9,10 @@ class C1 {
   virtual void f2(int);
   virtual void f2(double);
   virtual void f2(S1);
+
+private:
+  void f3(int);
+  void f4(int);
 };
 
 class C2 : public C1 {
@@ -81,4 +85,10 @@ void f2() {
 class C6 : public C1 {
 public:
   C6 &operator=(const C6 &); // COMPLIANT
+};
+
+class C7 : public C1 {
+  void f3(int); // COMPLIANT
+
+  void f4(int); // COMPLIANT
 };