Source code
Revision control
Copy as Markdown
Other Tools
// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_CONTAINER_BTREE_TEST_H_
#define ABSL_CONTAINER_BTREE_TEST_H_
#include <algorithm>
#include <cassert>
#include <random>
#include <string>
#include <utility>
#include <vector>
#include "absl/container/btree_map.h"
#include "absl/container/btree_set.h"
#include "absl/container/flat_hash_set.h"
#include "absl/strings/cord.h"
#include "absl/time/time.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace container_internal {
// Like remove_const but propagates the removal through std::pair.
template <typename T>
struct remove_pair_const {
using type = typename std::remove_const<T>::type;
};
template <typename T, typename U>
struct remove_pair_const<std::pair<T, U> > {
using type = std::pair<typename remove_pair_const<T>::type,
typename remove_pair_const<U>::type>;
};
// Utility class to provide an accessor for a key given a value. The default
// behavior is to treat the value as a pair and return the first element.
template <typename K, typename V>
struct KeyOfValue {
struct type {
const K& operator()(const V& p) const { return p.first; }
};
};
// Partial specialization of KeyOfValue class for when the key and value are
// the same type such as in set<> and btree_set<>.
template <typename K>
struct KeyOfValue<K, K> {
struct type {
const K& operator()(const K& k) const { return k; }
};
};
inline char* GenerateDigits(char buf[16], unsigned val, unsigned maxval) {
assert(val <= maxval);
constexpr unsigned kBase = 64; // avoid integer division.
unsigned p = 15;
buf[p--] = 0;
while (maxval > 0) {
buf[p--] = ' ' + (val % kBase);
val /= kBase;
maxval /= kBase;
}
return buf + p + 1;
}
template <typename K>
struct Generator {
int maxval;
explicit Generator(int m) : maxval(m) {}
K operator()(int i) const {
assert(i <= maxval);
return K(i);
}
};
template <>
struct Generator<absl::Time> {
int maxval;
explicit Generator(int m) : maxval(m) {}
absl::Time operator()(int i) const { return absl::FromUnixMillis(i); }
};
template <>
struct Generator<std::string> {
int maxval;
explicit Generator(int m) : maxval(m) {}
std::string operator()(int i) const {
char buf[16];
return GenerateDigits(buf, i, maxval);
}
};
template <>
struct Generator<Cord> {
int maxval;
explicit Generator(int m) : maxval(m) {}
Cord operator()(int i) const {
char buf[16];
return Cord(GenerateDigits(buf, i, maxval));
}
};
template <typename T, typename U>
struct Generator<std::pair<T, U> > {
Generator<typename remove_pair_const<T>::type> tgen;
Generator<typename remove_pair_const<U>::type> ugen;
explicit Generator(int m) : tgen(m), ugen(m) {}
std::pair<T, U> operator()(int i) const {
return std::make_pair(tgen(i), ugen(i));
}
};
// Generate n values for our tests and benchmarks. Value range is [0, maxval].
inline std::vector<int> GenerateNumbersWithSeed(int n, int maxval, int seed) {
// NOTE: Some tests rely on generated numbers not changing between test runs.
// We use std::minstd_rand0 because it is well-defined, but don't use
// std::uniform_int_distribution because platforms use different algorithms.
std::minstd_rand0 rng(seed);
std::vector<int> values;
absl::flat_hash_set<int> unique_values;
if (values.size() < n) {
for (int i = values.size(); i < n; i++) {
int value;
do {
value = static_cast<int>(rng()) % (maxval + 1);
} while (!unique_values.insert(value).second);
values.push_back(value);
}
}
return values;
}
// Generates n values in the range [0, maxval].
template <typename V>
std::vector<V> GenerateValuesWithSeed(int n, int maxval, int seed) {
const std::vector<int> nums = GenerateNumbersWithSeed(n, maxval, seed);
Generator<V> gen(maxval);
std::vector<V> vec;
vec.reserve(n);
for (int i = 0; i < n; i++) {
vec.push_back(gen(nums[i]));
}
return vec;
}
} // namespace container_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_CONTAINER_BTREE_TEST_H_