STL: suspicious condition when using std::find

lib/checkstl.cpp

@@ -557,6 +557,20 @@ void CheckStl::if_find()
                     if_findError(tok, false);
             }
         }
+
+        if (Token::Match(tok, "if ( !| std :: find|find_if ("))
+        {
+            // goto '(' for the find
+            tok = tok->tokAt(4);
+            if (tok->isName())
+                tok = tok->next();
+
+            // check that result is checked properly
+            if (Token::simpleMatch(tok->link(), ") )"))
+            {
+                if_findError(tok, false);
+            }
+        }
     }
 }
 

test/teststl.cpp

@@ -682,6 +682,25 @@ private:
               "    if (s.find(123) != s.end()) { }\n"
               "}\n");
         ASSERT_EQUALS("", errout.str());
+
+
+        // ---------------------------
+        // std::find
+        // ---------------------------
+
+        // error
+        check("void f()\n"
+              "{\n"
+              "    if (std::find(a,b,c)) { }\n"
+              "}\n");
+        ASSERT_EQUALS("[test.cpp:3]: (style) Suspicious condition. The result of find is an iterator, but it is not properly checked.\n", errout.str());
+
+        // ok
+        check("void f()\n"
+              "{\n"
+              "    if (std::find(a,b,c) != c) { }\n"
+              "}\n");
+        ASSERT_EQUALS("", errout.str());
     }