Files
abseil-cpp/absl/random/internal/mock_validators.h
Justin Bassett e7f1a950e9 Support int128/uint128 in validated MockingBitGen
`absl::int128` and `absl::uint128` are not `std::is_integral`. There is an internal `IsIntegral` type trait we could use, but it actually makes more sense to remove the `static_assert` altogether. Any compile-time validation should be done in `absl::Uniform` itself, and duplicating that logic here just increases the chance of divergence.

PiperOrigin-RevId: 635971431
Change-Id: I9177ae64c86ee1abe6571e0b29aba1844553c972
2024-05-21 16:57:23 -07:00

99 lines
3.8 KiB
C++

// Copyright 2024 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
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// 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_RANDOM_INTERNAL_MOCK_VALIDATORS_H_
#define ABSL_RANDOM_INTERNAL_MOCK_VALIDATORS_H_
#include <type_traits>
#include "absl/base/config.h"
#include "absl/base/internal/raw_logging.h"
#include "absl/random/internal/iostream_state_saver.h"
#include "absl/random/internal/uniform_helper.h"
#include "absl/strings/str_cat.h"
#include "absl/strings/string_view.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace random_internal {
template <typename NumType>
class UniformDistributionValidator {
public:
// Handle absl::Uniform<NumType>(gen, absl::IntervalTag, lo, hi).
template <typename TagType>
static void Validate(NumType x, TagType tag, NumType lo, NumType hi) {
// For invalid ranges, absl::Uniform() simply returns one of the bounds.
if (x == lo && lo == hi) return;
ValidateImpl(std::is_floating_point<NumType>{}, x, tag, lo, hi);
}
// Handle absl::Uniform<NumType>(gen, lo, hi).
static void Validate(NumType x, NumType lo, NumType hi) {
Validate(x, IntervalClosedOpenTag(), lo, hi);
}
// Handle absl::Uniform<NumType>(gen).
static void Validate(NumType) {
// absl::Uniform<NumType>(gen) spans the entire range of `NumType`, so any
// value is okay. This overload exists because the validation logic attempts
// to call it anyway rather than adding extra SFINAE.
}
private:
static absl::string_view TagLbBound(IntervalClosedOpenTag) { return "["; }
static absl::string_view TagLbBound(IntervalOpenOpenTag) { return "("; }
static absl::string_view TagLbBound(IntervalClosedClosedTag) { return "["; }
static absl::string_view TagLbBound(IntervalOpenClosedTag) { return "("; }
static absl::string_view TagUbBound(IntervalClosedOpenTag) { return ")"; }
static absl::string_view TagUbBound(IntervalOpenOpenTag) { return ")"; }
static absl::string_view TagUbBound(IntervalClosedClosedTag) { return "]"; }
static absl::string_view TagUbBound(IntervalOpenClosedTag) { return "]"; }
template <typename TagType>
static void ValidateImpl(std::true_type /* is_floating_point */, NumType x,
TagType tag, NumType lo, NumType hi) {
UniformDistributionWrapper<NumType> dist(tag, lo, hi);
NumType lb = dist.a();
NumType ub = dist.b();
// uniform_real_distribution is always closed-open, so the upper bound is
// always non-inclusive.
ABSL_INTERNAL_CHECK(lb <= x && x < ub,
absl::StrCat(x, " is not in ", TagLbBound(tag), lo,
", ", hi, TagUbBound(tag)));
}
template <typename TagType>
static void ValidateImpl(std::false_type /* is_floating_point */, NumType x,
TagType tag, NumType lo, NumType hi) {
using stream_type =
typename random_internal::stream_format_type<NumType>::type;
UniformDistributionWrapper<NumType> dist(tag, lo, hi);
NumType lb = dist.a();
NumType ub = dist.b();
ABSL_INTERNAL_CHECK(
lb <= x && x <= ub,
absl::StrCat(stream_type{x}, " is not in ", TagLbBound(tag),
stream_type{lo}, ", ", stream_type{hi}, TagUbBound(tag)));
}
};
} // namespace random_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_RANDOM_INTERNAL_MOCK_VALIDATORS_H_