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Fixed #4938: (.empty() method false positive for non-STL classes)

This commit is contained in:
Lucas Manuel Rodriguez 2014-01-30 18:09:24 -03:00
parent d6e3b3d3f3
commit a34d2eb7b3
2 changed files with 58 additions and 20 deletions
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50
lib/checkstl.cpp
View File

@ -1132,6 +1132,15 @@ static bool isLocal(const Token *tok)
void CheckStl::string_c_str()
{
// THIS ARRAY MUST BE ORDERED ALPHABETICALLY
static const char* const stl_string[] = {
"string", "u16string", "u32string", "wstring"
};
// THIS ARRAY MUST BE ORDERED ALPHABETICALLY
static const char* const stl_string_stream[] = {
"istringstream", "ostringstream", "stringstream", "wstringstream"
};
const SymbolDatabase* symbolDatabase = _tokenizer->getSymbolDatabase();
// Find all functions that take std::string as argument
@ -1170,11 +1179,13 @@ void CheckStl::string_c_str()
for (const Token *tok = scope->classStart; tok && tok != scope->classEnd; tok = tok->next()) {
// Invalid usage..
if (Token::Match(tok, "throw %var% . c_str ( ) ;") && isLocal(tok->next())) {
if (Token::Match(tok, "throw %var% . c_str ( ) ;") && isLocal(tok->next()) &&
tok->next()->variable() && tok->next()->variable()->isStlType(stl_string)) {
string_c_strThrowError(tok);
} else if (Token::Match(tok, "[;{}] %var% = %var% . str ( ) . c_str ( ) ;")) {
const Variable* var = tok->next()->variable();
if (var && var->isPointer())
const Variable* var2 = tok->tokAt(3)->variable();
if (var && var->isPointer() && var2 && var2->isStlType(stl_string_stream))
string_c_strError(tok);
} else if (Token::Match(tok, "[;{}] %var% = %var% (") &&
Token::simpleMatch(tok->linkAt(4), ") . c_str ( ) ;") &&
@ -1203,17 +1214,25 @@ void CheckStl::string_c_str()
tok2 = tok2->previous();
if (tok2 && Token::simpleMatch(tok2->tokAt(-4), ". c_str ( )")) {
const Variable* var = tok2->tokAt(-5)->variable();
if (var && var->isStlType())
if (var && var->isStlType(stl_string)) {
string_c_strParam(tok, i->second);
} else if (Token::Match(tok2->tokAt(-9), "%var% . str ( )")) { // Check ss.str().c_str() as parameter
const Variable* ssVar = tok2->tokAt(-9)->variable();
if (ssVar && ssVar->isStlType(stl_string_stream))
string_c_strParam(tok, i->second);
}
}
}
}
// Using c_str() to get the return value is only dangerous if the function returns a char*
if (returnType == charPtr) {
if (Token::Match(tok, "return %var% . c_str ( ) ;") && isLocal(tok->next())) {
if (Token::Match(tok, "return %var% . c_str ( ) ;") && isLocal(tok->next()) &&
tok->next()->variable() && tok->next()->variable()->isStlType(stl_string)) {
string_c_strError(tok);
} else if (Token::Match(tok, "return %var% . str ( ) . c_str ( ) ;") && isLocal(tok->next())) {
} else if (Token::Match(tok, "return %var% . str ( ) . c_str ( ) ;") && isLocal(tok->next()) &&
tok->next()->variable() && tok->next()->variable()->isStlType(stl_string_stream)) {
string_c_strError(tok);
} else if (Token::Match(tok, "return std :: string|wstring (") &&
Token::simpleMatch(tok->linkAt(4), ") . c_str ( ) ;")) {
@ -1228,7 +1247,8 @@ void CheckStl::string_c_str()
bool is_implicit_std_string = _settings->inconclusive;
const Token *search_end = tok->next()->link();
for (const Token *search_tok = tok->tokAt(2); search_tok != search_end; search_tok = search_tok->next()) {
if (Token::Match(search_tok, "+ %var%") && isLocal(search_tok->next())) {
if (Token::Match(search_tok, "+ %var%") && isLocal(search_tok->next()) &&
search_tok->next()->variable() && search_tok->next()->variable()->isStlType(stl_string)) {
is_implicit_std_string = true;
break;
} else if (Token::Match(search_tok, "+ std :: string|wstring (")) {
@ -1247,12 +1267,7 @@ void CheckStl::string_c_str()
const Token* tok2 = Token::findsimplematch(tok->next(), ";");
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 = tok2->variable();
if (var && var->isStlType())
string_c_strReturn(tok);
} else {
// TODO: determine if a error should be written or not
if (tok2->variable() && tok2->variable()->isStlType(stl_string)) { // return var.c_str();
string_c_strReturn(tok);
}
}
@ -1387,6 +1402,14 @@ void CheckStl::autoPointerArrayError(const Token *tok)
void CheckStl::uselessCalls()
{
// THIS ARRAY MUST BE ORDERED ALPHABETICALLY
static const char* const stl_containers_with_empty_and_clear[] = {
"deque", "forward_list", "list",
"map", "multimap", "multiset", "set", "string",
"unordered_map", "unordered_multimap", "unordered_multiset",
"unordered_set", "vector", "wstring"
};
bool performance = _settings->isEnabled("performance");
bool warning = _settings->isEnabled("warning");
if (!performance && !warning)
@ -1411,7 +1434,8 @@ void CheckStl::uselessCalls()
uselessCallsSubstrError(tok, false);
} else if (Token::simpleMatch(tok->linkAt(2)->tokAt(-2), ", 0 )"))
uselessCallsSubstrError(tok, true);
} else if (Token::Match(tok, "[{};] %var% . empty ( ) ;") && warning)
} else if (Token::Match(tok, "[{};] %var% . empty ( ) ;") && warning &&
tok->next()->variable() && tok->next()->variable()->isStlType(stl_containers_with_empty_and_clear))
uselessCallsEmptyError(tok->next());
else if (Token::Match(tok, "[{};] std :: remove|remove_if|unique (") && tok->tokAt(5)->nextArgument())
uselessCallsRemoveError(tok->next(), tok->strAt(3));

28
test/teststl.cpp
View File

@ -1922,13 +1922,13 @@ private:
"}");
ASSERT_EQUALS("", errout.str());
check("void Foo1(const std::string& str) {}\n"
"void Foo2(char* c, const std::string str) {}\n"
"void Foo3(std::string& rstr) {}\n"
"void Foo4(std::string str, const std::string& str) {}\n"
"void Bar() {\n"
" std::string str = \"bar\";\n"
" std::stringstream ss(\"foo\");\n"
" Foo1(str);\n"
" Foo1(str.c_str());\n"
" Foo2(str.c_str(), str);\n"
@ -1937,14 +1937,17 @@ private:
" Foo4(str, str);\n"
" Foo4(str.c_str(), str);\n"
" Foo4(str, str.c_str());\n"
" Foo4(ss.str(), ss.str().c_str());\n"
" Foo4(str.c_str(), str.c_str());\n"
"}");
ASSERT_EQUALS("[test.cpp:8]: (performance) Passing the result of c_str() to a function that takes std::string as argument no. 1 is slow and redundant.\n"
"[test.cpp:10]: (performance) Passing the result of c_str() to a function that takes std::string as argument no. 2 is slow and redundant.\n"
"[test.cpp:13]: (performance) Passing the result of c_str() to a function that takes std::string as argument no. 1 is slow and redundant.\n"
"[test.cpp:14]: (performance) Passing the result of c_str() to a function that takes std::string as argument no. 2 is slow and redundant.\n"
"[test.cpp:15]: (performance) Passing the result of c_str() to a function that takes std::string as argument no. 1 is slow and redundant.\n"
"[test.cpp:15]: (performance) Passing the result of c_str() to a function that takes std::string as argument no. 2 is slow and redundant.\n", errout.str());
ASSERT_EQUALS("[test.cpp:9]: (performance) Passing the result of c_str() to a function that takes std::string as argument no. 1 is slow and redundant.\n"
"[test.cpp:11]: (performance) Passing the result of c_str() to a function that takes std::string as argument no. 2 is slow and redundant.\n"
"[test.cpp:14]: (performance) Passing the result of c_str() to a function that takes std::string as argument no. 1 is slow and redundant.\n"
"[test.cpp:15]: (performance) Passing the result of c_str() to a function that takes std::string as argument no. 2 is slow and redundant.\n"
"[test.cpp:16]: (performance) Passing the result of c_str() to a function that takes std::string as argument no. 2 is slow and redundant.\n"
"[test.cpp:17]: (performance) Passing the result of c_str() to a function that takes std::string as argument no. 1 is slow and redundant.\n"
"[test.cpp:17]: (performance) Passing the result of c_str() to a function that takes std::string as argument no. 2 is slow and redundant.\n", errout.str());
check("void Foo1(const std::string& str) {}\n"
"void Foo2(char* c, const std::string str) {}\n"
@ -2026,6 +2029,11 @@ private:
" a(s.c_str());\n"
"}");
ASSERT_EQUALS("", errout.str());
check("std::string Format(const char * name) {\n" // #4938
" return String::Format(\"%s:\", name).c_str();\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void autoPointer() {
@ -2233,6 +2241,12 @@ private:
"}");
ASSERT_EQUALS("[test.cpp:2]: (warning) Ineffective call of function 'empty()'. Did you intend to call 'clear()' instead?\n", errout.str());
check("void f() {\n" // #4938
" OdString str;\n"
" str.empty();\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f() {\n" // #4032
" const std::string greeting(\"Hello World !!!\");\n"
" const std::string::size_type npos = greeting.rfind(\" \");\n"