Fixed #9218 (False positive: Searching before insertion is not necessary (stlFindInsert))

Author: danmar

lib/checkstl.cpp

@@ -1558,6 +1558,9 @@ void CheckStl::checkFindInsert()
             std::tie(containerTok, keyTok) = isMapFind(condTok->astOperand1());
             if (!containerTok)
                 continue;
+            // In < C++17 we only warn for small simple types
+            if (!(keyTok->valueType()->isIntegral() || keyTok->valueType()->pointer > 0) && mSettings->standards.cpp < Standards::CPP17)
+                continue;
 
             const Token *thenTok = tok->next()->link()->next();
             const Token *valueTok = findInsertValue(thenTok, containerTok, keyTok, mSettings->library);

test/teststl.cpp

@@ -4726,6 +4726,21 @@ class TestStl : public TestFixture {
               "}\n",
               true);
         ASSERT_EQUALS("", errout.str());
+
+        // #9218 - not small type => do not warn if cpp standard is < c++17
+        {
+            const char code[] = "void f1(std::set<LargeType>& s, const LargeType& x) {\n"
+                                "    if (s.find(x) == s.end()) {\n"
+                                "        s.insert(x);\n"
+                                "    }\n"
+                                "}\n";
+            check(code, true, Standards::CPP11);
+            ASSERT_EQUALS("", errout.str());
+            check(code, true, Standards::CPP14);
+            ASSERT_EQUALS("", errout.str());
+            check(code, true, Standards::CPP17);
+            ASSERT_EQUALS("[test.cpp:3]: (performance) Searching before insertion is not necessary.\n", errout.str());
+        }
     }
 
     void checkKnownEmptyContainer() {