performance-inefficient-algorithm.cpp
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// RUN: %check_clang_tidy -std=c++11,c++14 %s performance-inefficient-algorithm %t
// FIXME: Fix the checker to work in C++17 mode.
namespace std {
template <typename T> struct less {
bool operator()(const T &lhs, const T &rhs) { return lhs < rhs; }
};
template <typename T> struct greater {
bool operator()(const T &lhs, const T &rhs) { return lhs > rhs; }
};
struct iterator_type {};
template <typename K, typename Cmp = less<K>> struct set {
typedef iterator_type iterator;
iterator find(const K &k);
unsigned count(const K &k);
iterator begin();
iterator end();
iterator begin() const;
iterator end() const;
};
struct other_iterator_type {};
template <typename K, typename V, typename Cmp = less<K>> struct map {
typedef other_iterator_type iterator;
iterator find(const K &k);
unsigned count(const K &k);
iterator begin();
iterator end();
iterator begin() const;
iterator end() const;
};
template <typename K, typename V> struct multimap : map<K, V> {};
template <typename K> struct unordered_set : set<K> {};
template <typename K, typename V> struct unordered_map : map<K, V> {};
template <typename K> struct unordered_multiset : set<K> {};
template <typename K, typename V> struct unordered_multimap : map<K, V> {};
template <typename K, typename Cmp = less<K>> struct multiset : set<K, Cmp> {};
template <typename FwIt, typename K>
FwIt find(FwIt, FwIt end, const K &) { return end; }
template <typename FwIt, typename K, typename Cmp>
FwIt find(FwIt, FwIt end, const K &, Cmp) { return end; }
template <typename FwIt, typename Pred>
FwIt find_if(FwIt, FwIt end, Pred) { return end; }
template <typename FwIt, typename K>
unsigned count(FwIt, FwIt, const K &) { return 0; }
template <typename FwIt, typename K>
FwIt lower_bound(FwIt, FwIt end, const K &) { return end; }
template <typename FwIt, typename K, typename Ord>
FwIt lower_bound(FwIt, FwIt end, const K &, Ord) { return end; }
}
#define FIND_IN_SET(x) find(x.begin(), x.end(), 10)
// CHECK-FIXES: #define FIND_IN_SET(x) find(x.begin(), x.end(), 10)
template <typename T> void f(const T &t) {
std::set<int> s;
find(s.begin(), s.end(), 46);
// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: this STL algorithm call should be
// CHECK-FIXES: {{^ }}s.find(46);{{$}}
find(t.begin(), t.end(), 46);
// CHECK-FIXES: {{^ }}find(t.begin(), t.end(), 46);{{$}}
}
int main() {
std::set<int> s;
auto it = std::find(s.begin(), s.end(), 43);
// CHECK-MESSAGES: :[[@LINE-1]]:13: warning: this STL algorithm call should be replaced with a container method [performance-inefficient-algorithm]
// CHECK-FIXES: {{^ }}auto it = s.find(43);{{$}}
auto c = count(s.begin(), s.end(), 43);
// CHECK-MESSAGES: :[[@LINE-1]]:12: warning: this STL algorithm call should be
// CHECK-FIXES: {{^ }}auto c = s.count(43);{{$}}
#define SECOND(x, y, z) y
SECOND(q,std::count(s.begin(), s.end(), 22),w);
// CHECK-MESSAGES: :[[@LINE-1]]:12: warning: this STL algorithm call should be
// CHECK-FIXES: {{^ }}SECOND(q,s.count(22),w);{{$}}
it = find_if(s.begin(), s.end(), [](int) { return false; });
std::multiset<int> ms;
find(ms.begin(), ms.end(), 46);
// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: this STL algorithm call should be
// CHECK-FIXES: {{^ }}ms.find(46);{{$}}
const std::multiset<int> &msref = ms;
find(msref.begin(), msref.end(), 46);
// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: this STL algorithm call should be
// CHECK-FIXES: {{^ }}msref.find(46);{{$}}
std::multiset<int> *msptr = &ms;
find(msptr->begin(), msptr->end(), 46);
// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: this STL algorithm call should be
// CHECK-FIXES: {{^ }}msptr->find(46);{{$}}
it = std::find(s.begin(), s.end(), 43, std::greater<int>());
// CHECK-MESSAGES: :[[@LINE-1]]:42: warning: different comparers used in the algorithm and the container [performance-inefficient-algorithm]
FIND_IN_SET(s);
// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: this STL algorithm call should be
// CHECK-FIXES: {{^ }}FIND_IN_SET(s);{{$}}
f(s);
std::unordered_set<int> us;
lower_bound(us.begin(), us.end(), 10);
// CHECK-FIXES: {{^ }}lower_bound(us.begin(), us.end(), 10);{{$}}
find(us.begin(), us.end(), 10);
// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: this STL algorithm call should be
// CHECK-FIXES: {{^ }}us.find(10);{{$}}
std::unordered_multiset<int> ums;
find(ums.begin(), ums.end(), 10);
// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: this STL algorithm call should be
// CHECK-FIXES: {{^ }}ums.find(10);{{$}}
std::map<int, int> intmap;
find(intmap.begin(), intmap.end(), 46);
// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: this STL algorithm call should be
// CHECK-FIXES: {{^ }}find(intmap.begin(), intmap.end(), 46);{{$}}
std::multimap<int, int> intmmap;
find(intmmap.begin(), intmmap.end(), 46);
// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: this STL algorithm call should be
// CHECK-FIXES: {{^ }}find(intmmap.begin(), intmmap.end(), 46);{{$}}
std::unordered_map<int, int> umap;
find(umap.begin(), umap.end(), 46);
// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: this STL algorithm call should be
// CHECK-FIXES: {{^ }}find(umap.begin(), umap.end(), 46);{{$}}
std::unordered_multimap<int, int> ummap;
find(ummap.begin(), ummap.end(), 46);
// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: this STL algorithm call should be
// CHECK-FIXES: {{^ }}find(ummap.begin(), ummap.end(), 46);{{$}}
}
struct Value {
int value;
};
struct Ordering {
bool operator()(const Value &lhs, const Value &rhs) const {
return lhs.value < rhs.value;
}
bool operator()(int lhs, const Value &rhs) const { return lhs < rhs.value; }
};
void g(std::set<Value, Ordering> container, int value) {
lower_bound(container.begin(), container.end(), value, Ordering());
// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: this STL algorithm call should be
// CHECK-FIXES: {{^ }}lower_bound(container.begin(), container.end(), value, Ordering());{{$}}
}