Fixed cppcheck-opensource#3678 (stlcstrReturn for classes which don't provide a std::string)

danmar · danmar · commit ba3833c692eb · 2012-11-29T07:10:56.000+01:00
diff --git a/lib/checkstl.cpp b/lib/checkstl.cpp
@@ -1196,7 +1196,7 @@ void CheckStl::string_c_str()
                         tok2 = tok2->previous();
                     if (tok2 && Token::simpleMatch(tok2->tokAt(-4), ". c_str ( )")) {
                         const Variable* var = symbolDatabase->getVariableFromVarId(tok2->tokAt(-5)->varId());
-                        if (var && Token::Match(var->typeStartToken(), "const| std :: string|wstring"))
+                        if (var && Token::Match(var->typeStartToken(), "const| std ::"))
                             string_c_strParam(tok, i->second);
                     }
                 }
@@ -1238,8 +1238,17 @@ void CheckStl::string_c_str()
             else if ((returnType == stdString || returnType == stdStringConstRef) && _settings->isEnabled("performance")) {
                 if (tok->str() == "return") {
                     const Token* tok2 = Token::findsimplematch(tok->next(), ";");
-                    if (Token::simpleMatch(tok2->tokAt(-4), ". c_str ( )"))
-                        string_c_strReturn(tok);
+                    if (Token::simpleMatch(tok2->tokAt(-4), ". c_str ( )")) {
+                        tok2 = tok2->tokAt(-5);
+                        if (tok2->isName()) {  // return var.c_str(); => check if var is a std type
+                            const Variable* var = symbolDatabase->getVariableFromVarId(tok2->varId());
+                            if (var && Token::Match(var->typeStartToken(), "const| std ::"))
+                                string_c_strReturn(tok);
+                        } else {
+                            // TODO: determine if a error should be written or not
+                            string_c_strReturn(tok);
+                        }
+                    }
                 }
             }
         }
diff --git a/test/teststl.cpp b/test/teststl.cpp
@@ -1769,6 +1769,12 @@ class TestStl : public TestFixture {
               "}");
         ASSERT_EQUALS("", errout.str());
 
+        check("std::string get_msg() {\n" // #3678
+              "    MyStringClass errmsg;\n"
+              "    return errmsg.c_str();\n"
+              "}");
+        ASSERT_EQUALS("", errout.str());
+
 
         check("void Foo1(const std::string& str) {}\n"
               "void Foo2(char* c, const std::string str) {}\n"

Original file line number	Diff line number	Diff line change
`@@ -1196,7 +1196,7 @@ void CheckStl::string_c_str()`
`1196`	`1196`	`tok2 = tok2->previous();`
`1197`	`1197`	`if (tok2 && Token::simpleMatch(tok2->tokAt(-4), ". c_str ( )")) {`
`1198`	`1198`	`const Variable* var = symbolDatabase->getVariableFromVarId(tok2->tokAt(-5)->varId());`
`1199`		`- if (var && Token::Match(var->typeStartToken(), "const\| std :: string\|wstring"))`
	`1199`	`+ if (var && Token::Match(var->typeStartToken(), "const\| std ::"))`
`1200`	`1200`	`string_c_strParam(tok, i->second);`
`1201`	`1201`	`}`
`1202`	`1202`	`}`
`@@ -1238,8 +1238,17 @@ void CheckStl::string_c_str()`
`1238`	`1238`	`else if ((returnType == stdString \|\| returnType == stdStringConstRef) && _settings->isEnabled("performance")) {`
`1239`	`1239`	`if (tok->str() == "return") {`
`1240`	`1240`	`const Token* tok2 = Token::findsimplematch(tok->next(), ";");`
`1241`		`- if (Token::simpleMatch(tok2->tokAt(-4), ". c_str ( )"))`
`1242`		`- string_c_strReturn(tok);`
	`1241`	`+ if (Token::simpleMatch(tok2->tokAt(-4), ". c_str ( )")) {`
	`1242`	`+ tok2 = tok2->tokAt(-5);`
	`1243`	`+ if (tok2->isName()) { // return var.c_str(); => check if var is a std type`
	`1244`	`+ const Variable* var = symbolDatabase->getVariableFromVarId(tok2->varId());`
	`1245`	`+ if (var && Token::Match(var->typeStartToken(), "const\| std ::"))`
	`1246`	`+ string_c_strReturn(tok);`
	`1247`	`+ } else {`
	`1248`	`+ // TODO: determine if a error should be written or not`
	`1249`	`+ string_c_strReturn(tok);`
	`1250`	`+ }`
	`1251`	`+ }`
`1243`	`1252`	`}`
`1244`	`1253`	`}`
`1245`	`1254`	`}`