ccls/src/utils.h

#pragma once

#include <functional>
#include <memory>
#include <queue>
#include <string>
#include <unordered_map>
#include <vector>

// Returns true if |value| starts/ends with |start| or |ending|.
bool StartsWith(const std::string& value, const std::string& start);
bool EndsWith(const std::string& value, const std::string& ending);

// Finds all files in the given folder. This is recursive.
std::vector<std::string> GetFilesInFolder(std::string folder, bool recursive, bool add_folder_to_path);
std::vector<std::string> ReadLines(std::string filename);
std::unordered_map<std::string, std::string> ParseTestExpectation(std::string filename);

void Fail(const std::string& message);


void WriteToFile(const std::string& filename, const std::string& content);

// note: this implementation does not disable this overload for array types
// See http://en.cppreference.com/w/cpp/memory/unique_ptr/make_unique#Possible_Implementatiog
template<typename T, typename... Args>
std::unique_ptr<T> MakeUnique(Args&&... args) {
    return std::unique_ptr<T>(new T(std::forward<Args>(args)...));
}

template<typename T>
void AddRange(std::vector<T>* dest, const std::vector<T>& to_add) {
  for (const T& e : to_add)
    dest->push_back(e);
}

template<typename T>
void PushRange(std::queue<T>* dest, const std::vector<T>& to_add) {
  for (const T& e : to_add)
    dest->push(e);
}

template<typename T>
void RemoveRange(std::vector<T>* dest, const std::vector<T>& to_remove) {
  auto it = std::remove_if(dest->begin(), dest->end(), [&](const T& t) {
    // TODO: make to_remove a set?
    return std::find(to_remove.begin(), to_remove.end(), t) != to_remove.end();
  });
  if (it != dest->end())
    dest->erase(it);
}

// http://stackoverflow.com/a/38140932
//
//  struct SomeHashKey {
//    std::string key1;
//    std::string key2;
//    bool key3;
//  };
//  MAKE_HASHABLE(SomeHashKey, t.key1, t.key2, t.key3)

inline void hash_combine(std::size_t& seed) { }

template <typename T, typename... Rest>
inline void hash_combine(std::size_t& seed, const T& v, Rest... rest) {
  std::hash<T> hasher;
  seed ^= hasher(v) + 0x9e3779b9 + (seed << 6) + (seed >> 2);
  hash_combine(seed, rest...);
}

#define MAKE_HASHABLE(type, ...) \
    namespace std {\
        template<> struct hash<type> {\
            std::size_t operator()(const type &t) const {\
                std::size_t ret = 0;\
                hash_combine(ret, __VA_ARGS__);\
                return ret;\
            }\
        };\
    }

#define MAKE_ENUM_HASHABLE(type) \
    namespace std {\
        template<> struct hash<type> {\
            std::size_t operator()(const type &t) const {\
                return hash<int>()(static_cast<int>(t));\
            }\
        };\
    }