STL: Fixed false positive when using string::find

lib/checkstl.cpp

@@ -60,6 +60,13 @@ void CheckStl::iterators()
         if (iteratorId == 0 || containerId == 0)
             continue;
 
+        // check that it's an iterator..
+        {
+            const Variable *var = _tokenizer->getSymbolDatabase()->getVariableFromVarId(iteratorId);
+            if (!var || !Token::Match(var->nameToken()->previous(), "iterator|const_iterator|reverse_iterator|const_reverse_iterator"))
+                continue;
+        }
+
         // the validIterator flag says if the iterator has a valid value or not
         bool validIterator = true;
         const Token* validatingToken = 0;

test/teststl.cpp

@@ -361,6 +361,13 @@ private:
               "    if (it == map2.end()) { }"
               "}\n");
         ASSERT_EQUALS("[test.cpp:5]: (error) Same iterator is used with both map1 and map2\n", errout.str());
+
+        check("void f(std::string &s) {\n"
+              "    int pos = s.find(x);\n"
+              "    s.erase(pos);\n"
+              "    s.erase(pos);\n"
+              "}");
+        ASSERT_EQUALS("", errout.str());
     }
 
     // Dereferencing invalid pointer