Fixed cppcheck-opensource#4723 (False positive: Pure virtual call within conditional clause)

zingsheim · zingsheim · commit 445d08d0825e · 2013-09-26T17:25:16.000+02:00
diff --git a/lib/checkclass.cpp b/lib/checkclass.cpp
@@ -1994,8 +1994,17 @@ const std::list<const Token *> & CheckClass::callsPureVirtualFunction(const Func
     if (found.second) {
         if (function.hasBody) {
             for (const Token *tok = function.arg->link();
-                 tok != function.functionScope->classEnd;
+                 tok && tok != function.functionScope->classEnd;
                  tok = tok->next()) {
+                if ((Token::simpleMatch(tok,") {") &&
+                     tok->link() &&
+                     Token::Match(tok->link()->previous(),"if|switch")) ||
+                    Token::simpleMatch(tok,"else {")
+                   ) {
+                    // Assume pure virtual function call is prevented by "if|else|switch" condition
+                    tok = tok->linkAt(1);
+                    continue;
+                }
                 const Function * callFunction=tok->function();
                 if (!callFunction ||
                     function.nestedIn != callFunction->nestedIn ||
diff --git a/test/testclass.cpp b/test/testclass.cpp
@@ -176,6 +176,7 @@ class TestClass : public TestFixture {
         TEST_CASE(pureVirtualFunctionCall);
         TEST_CASE(pureVirtualFunctionCallOtherClass);
         TEST_CASE(pureVirtualFunctionCallWithBody);
+        TEST_CASE(pureVirtualFunctionCallPrevented);
 
         TEST_CASE(duplInheritedMembers);
     }
@@ -5731,6 +5732,45 @@ class TestClass : public TestFixture {
 
     }
 
+    void pureVirtualFunctionCallPrevented() {
+        checkPureVirtualFunctionCall("class A\n"
+                                     " {\n"
+                                     "    virtual void pure()=0;\n"
+                                     "    void nonpure(bool bCallPure)\n"
+                                     "    { if (bCallPure) pure();}\n"
+                                     "    A(); \n"
+                                     "};\n"
+                                     "A::A()\n"
+                                     "{nonpure(false);}\n");
+        ASSERT_EQUALS("", errout.str());
+
+        checkPureVirtualFunctionCall("class A\n"
+                                     " {\n"
+                                     "    virtual void pure()=0;\n"
+                                     "    void nonpure(bool bCallPure)\n"
+                                     "    { if (!bCallPure) ; else pure();}\n"
+                                     "    A(); \n"
+                                     "};\n"
+                                     "A::A()\n"
+                                     "{nonpure(false);}\n");
+        ASSERT_EQUALS("", errout.str());
+
+        checkPureVirtualFunctionCall("class A\n"
+                                     " {\n"
+                                     "    virtual void pure()=0;\n"
+                                     "    void nonpure(bool bCallPure)\n"
+                                     "    {\n"
+                                     "        switch (bCallPure) {\n"
+                                     "        case true: pure(); break;\n"
+                                     "        }\n"
+                                     "    }\n"
+                                     "    A(); \n"
+                                     "};\n"
+                                     "A::A()\n"
+                                     "{nonpure(false);}\n");
+        ASSERT_EQUALS("", errout.str());
+    }
+
 };
 
 REGISTER_TEST(TestClass)
