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_STRINGS_CORD_TEST_HELPERS_H_
#define ABSL_STRINGS_CORD_TEST_HELPERS_H_
#include <cstdint>
#include <iostream>
#include <string>
#include "absl/base/config.h"
#include "absl/strings/cord.h"
#include "absl/strings/internal/cord_internal.h"
#include "absl/strings/string_view.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
// Cord sizes relevant for testing
enum class TestCordSize {
// An empty value
kEmpty = 0,
// An inlined string value
kInlined = cord_internal::kMaxInline / 2 + 1,
// 'Well known' SSO lengths (excluding terminating zero).
// libstdcxx has a maximum SSO of 15, libc++ has a maximum SSO of 22.
kStringSso1 = 15,
kStringSso2 = 22,
// A string value which is too large to fit in inlined data, but small enough
// such that Cord prefers copying the value if possible, i.e.: not stealing
// std::string inputs, or referencing existing CordReps on Append, etc.
kSmall = cord_internal::kMaxBytesToCopy / 2 + 1,
// A string value large enough that Cord prefers to reference or steal from
// existing inputs rather than copying contents of the input.
kMedium = cord_internal::kMaxFlatLength / 2 + 1,
// A string value large enough to cause it to be stored in multiple flats.
kLarge = cord_internal::kMaxFlatLength * 4
};
// To string helper
inline absl::string_view ToString(TestCordSize size) {
switch (size) {
case TestCordSize::kEmpty:
return "Empty";
case TestCordSize::kInlined:
return "Inlined";
case TestCordSize::kSmall:
return "Small";
case TestCordSize::kStringSso1:
return "StringSso1";
case TestCordSize::kStringSso2:
return "StringSso2";
case TestCordSize::kMedium:
return "Medium";
case TestCordSize::kLarge:
return "Large";
}
return "???";
}
// Returns the length matching the specified size
inline size_t Length(TestCordSize size) { return static_cast<size_t>(size); }
// Stream output helper
inline std::ostream& operator<<(std::ostream& stream, TestCordSize size) {
return stream << ToString(size);
}
// Creates a multi-segment Cord from an iterable container of strings. The
// resulting Cord is guaranteed to have one segment for every string in the
// container. This allows code to be unit tested with multi-segment Cord
// inputs.
//
// Example:
//
// absl::Cord c = absl::MakeFragmentedCord({"A ", "fragmented ", "Cord"});
// EXPECT_FALSE(c.GetFlat(&unused));
//
// The mechanism by which this Cord is created is an implementation detail. Any
// implementation that produces a multi-segment Cord may produce a flat Cord in
// the future as new optimizations are added to the Cord class.
// MakeFragmentedCord will, however, always be updated to return a multi-segment
// Cord.
template <typename Container>
Cord MakeFragmentedCord(const Container& c) {
Cord result;
for (const auto& s : c) {
auto* external = new std::string(s);
Cord tmp = absl::MakeCordFromExternal(
*external, [external](absl::string_view) { delete external; });
tmp.Prepend(result);
result = tmp;
}
return result;
}
inline Cord MakeFragmentedCord(std::initializer_list<absl::string_view> list) {
return MakeFragmentedCord<std::initializer_list<absl::string_view>>(list);
}
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_STRINGS_CORD_TEST_HELPERS_H_