Export of internal Abseil changes.

--
7a6ff16a85beb730c172d5d25cf1b5e1be885c56 by Laramie Leavitt <lar@google.com>:

Internal change.

PiperOrigin-RevId: 254454546

--
ff8f9bafaefc26d451f576ea4a06d150aed63f6f by Andy Soffer <asoffer@google.com>:

Internal changes

PiperOrigin-RevId: 254451562

--
deefc5b651b479ce36f0b4ef203e119c0c8936f2 by CJ Johnson <johnsoncj@google.com>:

Account for subtracting unsigned values from the size of InlinedVector

PiperOrigin-RevId: 254450625

--
3c677316a27bcadc17e41957c809ca472d5fef14 by Andy Soffer <asoffer@google.com>:

Add C++17's std::make_from_tuple to absl/utility/utility.h

PiperOrigin-RevId: 254411573

--
4ee3536a918830eeec402a28fc31a62c7c90b940 by CJ Johnson <johnsoncj@google.com>:

Adds benchmark for the rest of the InlinedVector public API

PiperOrigin-RevId: 254408378

--
e5a21a00700ee83498ff1efbf649169756463ee4 by CJ Johnson <johnsoncj@google.com>:

Updates the definition of InlinedVector::shrink_to_fit() to be exception safe and adds exception safety tests for it.

PiperOrigin-RevId: 254401387

--
2ea82e72b86d82d78b4e4712a63a55981b53c64b by Laramie Leavitt <lar@google.com>:

Use absl::InsecureBitGen in place of std::mt19937
in tests absl/random/...distribution_test.cc

PiperOrigin-RevId: 254289444

--
fa099e02c413a7ffda732415e8105cad26a90337 by Andy Soffer <asoffer@google.com>:

Internal changes

PiperOrigin-RevId: 254286334

--
ce34b7f36933b30cfa35b9c9a5697a792b5666e4 by Andy Soffer <asoffer@google.com>:

Internal changes

PiperOrigin-RevId: 254273059

--
6f9c473da7c2090c2e85a37c5f00622e8a912a89 by Jorg Brown <jorg@google.com>:

Change absl::container_internal::CompressedTuple to instantiate its
internal Storage class with the name of the type it's holding, rather
than the name of the Tuple.  This is not an externally-visible change,
other than less compiler memory is used and less debug information is
generated.

PiperOrigin-RevId: 254269285

--
8bd3c186bf2fc0c55d8a2dd6f28a5327502c9fba by Andy Soffer <asoffer@google.com>:

Adding short-hand IntervalClosed for IntervalClosedClosed and IntervalOpen for
IntervalOpenOpen.

PiperOrigin-RevId: 254252419

--
ea957f99b6a04fccd42aa05605605f3b44b1ecfd by Abseil Team <absl-team@google.com>:

Do not directly use __SIZEOF_INT128__.

In order to avoid linker errors when building with clang-cl (__fixunsdfti, __udivti3 and __fixunssfti are undefined), this CL uses ABSL_HAVE_INTRINSIC_INT128 which is not defined for clang-cl.

PiperOrigin-RevId: 254250739

--
89ab385cd26b34d64130bce856253aaba96d2345 by Andy Soffer <asoffer@google.com>:

Internal changes

PiperOrigin-RevId: 254242321

--
cffc793d93eca6d6bdf7de733847b6ab4a255ae9 by CJ Johnson <johnsoncj@google.com>:

Adds benchmark for InlinedVector::reserve(size_type)

PiperOrigin-RevId: 254199226

--
c90c7a9fa3c8f0c9d5114036979548b055ea2f2a by Gennadiy Rozental <rogeeff@google.com>:

Import of CCTZ from GitHub.

PiperOrigin-RevId: 254072387

--
c4c388beae016c9570ab54ffa1d52660e4a85b7b by Laramie Leavitt <lar@google.com>:

Internal cleanup.

PiperOrigin-RevId: 254062381

--
d3c992e221cc74e5372d0c8fa410170b6a43c062 by Tom Manshreck <shreck@google.com>:

Update distributions.h to Abseil standards

PiperOrigin-RevId: 254054946

--
d15ad0035c34ef11b14fadc5a4a2d3ec415f5518 by CJ Johnson <johnsoncj@google.com>:

Removes functions with only one caller from the implementation details of InlinedVector by manually inlining the definitions

PiperOrigin-RevId: 254005427

--
2f37e807efc3a8ef1f4b539bdd379917d4151520 by Andy Soffer <asoffer@google.com>:

Initial release of Abseil Random

PiperOrigin-RevId: 253999861

--
24ed1694b6430791d781ed533a8f8ccf6cac5856 by CJ Johnson <johnsoncj@google.com>:

Updates the definition of InlinedVector::assign(...)/InlinedVector::operator=(...) to new, exception-safe implementations with exception safety tests to boot

PiperOrigin-RevId: 253993691

--
5613d95f5a7e34a535cfaeadce801441e990843e by CJ Johnson <johnsoncj@google.com>:

Adds benchmarks for InlinedVector::shrink_to_fit()

PiperOrigin-RevId: 253989647

--
2a96ddfdac40bbb8cb6a7f1aeab90917067c6e63 by Abseil Team <absl-team@google.com>:

Initial release of Abseil Random

PiperOrigin-RevId: 253927497

--
bf1aff8fc9ffa921ad74643e9525ecf25b0d8dc1 by Andy Soffer <asoffer@google.com>:

Initial release of Abseil Random

PiperOrigin-RevId: 253920512

--
bfc03f4a3dcda3cf3a4b84bdb84cda24e3394f41 by Laramie Leavitt <lar@google.com>:

Internal change.

PiperOrigin-RevId: 253886486

--
05036cfcc078ca7c5f581a00dfb0daed568cbb69 by Eric Fiselier <ericwf@google.com>:

Don't include `winsock2.h` because it drags in `windows.h` and friends,
and they define awful macros like OPAQUE, ERROR, and more. This has the
potential to break abseil users.

Instead we only forward declare `timeval` and require Windows users
include `winsock2.h` themselves. This is both inconsistent and poor QoI, but so
including 'windows.h' is bad too.

PiperOrigin-RevId: 253852615
GitOrigin-RevId: 7a6ff16a85beb730c172d5d25cf1b5e1be885c56
Change-Id: Icd6aff87da26f29ec8915da856f051129987cef6

1 files changed, 244 insertions, 0 deletions

diff --git a/absl/random/internal/nonsecure_base_test.cc b/absl/random/internal/nonsecure_base_test.cc
new file mode 100644
index 000000000000..d9de99019ce0
--- /dev/null
+++ b/absl/random/internal/nonsecure_base_test.cc
@@ -0,0 +1,244 @@
+// Copyright 2017 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.
+
+#include "absl/random/internal/nonsecure_base.h"
+
+#include <algorithm>
+#include <iostream>
+#include <memory>
+#include <random>
+#include <sstream>
+
+#include "gtest/gtest.h"
+#include "absl/random/distributions.h"
+#include "absl/random/random.h"
+#include "absl/strings/str_cat.h"
+
+namespace {
+
+using ExampleNonsecureURBG =
+    absl::random_internal::NonsecureURBGBase<std::mt19937>;
+
+template <typename T>
+void Use(const T&) {}
+
+}  // namespace
+
+TEST(NonsecureURBGBase, DefaultConstructorIsValid) {
+  ExampleNonsecureURBG urbg;
+}
+
+// Ensure that the recommended template-instantiations are valid.
+TEST(RecommendedTemplates, CanBeConstructed) {
+  absl::BitGen default_generator;
+  absl::InsecureBitGen insecure_generator;
+}
+
+TEST(RecommendedTemplates, CanDiscardValues) {
+  absl::BitGen default_generator;
+  absl::InsecureBitGen insecure_generator;
+
+  default_generator.discard(5);
+  insecure_generator.discard(5);
+}
+
+TEST(NonsecureURBGBase, StandardInterface) {
+  // Names after definition of [rand.req.urbg] in C++ standard.
+  // e us a value of E
+  // v is a lvalue of E
+  // x, y are possibly const values of E
+  // s is a value of T
+  // q is a value satisfying requirements of seed_sequence
+  // z is a value of type unsigned long long
+  // os is a some specialization of basic_ostream
+  // is is a some specialization of basic_istream
+
+  using E = absl::random_internal::NonsecureURBGBase<std::minstd_rand>;
+
+  using T = typename E::result_type;
+
+  static_assert(!std::is_copy_constructible<E>::value,
+                "NonsecureURBGBase should not be copy constructible");
+
+  static_assert(!absl::is_copy_assignable<E>::value,
+                "NonsecureURBGBase should not be copy assignable");
+
+  static_assert(std::is_move_constructible<E>::value,
+                "NonsecureURBGBase should be move constructible");
+
+  static_assert(absl::is_move_assignable<E>::value,
+                "NonsecureURBGBase should be move assignable");
+
+  static_assert(std::is_same<decltype(std::declval<E>()()), T>::value,
+                "return type of operator() must be result_type");
+
+  {
+    const E x, y;
+    Use(x);
+    Use(y);
+
+    static_assert(std::is_same<decltype(x == y), bool>::value,
+                  "return type of operator== must be bool");
+
+    static_assert(std::is_same<decltype(x != y), bool>::value,
+                  "return type of operator== must be bool");
+  }
+
+  E e;
+  std::seed_seq q{1, 2, 3};
+
+  E{};
+  E{q};
+
+  // Copy constructor not supported.
+  // E{x};
+
+  // result_type seed constructor not supported.
+  // E{T{1}};
+
+  // Move constructors are supported.
+  {
+    E tmp(q);
+    E m = std::move(tmp);
+    E n(std::move(m));
+    EXPECT_TRUE(e != n);
+  }
+
+  // Comparisons work.
+  {
+    // MSVC emits error 2718 when using EXPECT_EQ(e, x)
+    //  * actual parameter with __declspec(align('#')) won't be aligned
+    E a(q);
+    E b(q);
+
+    EXPECT_TRUE(a != e);
+    EXPECT_TRUE(a == b);
+
+    a();
+    EXPECT_TRUE(a != b);
+  }
+
+  // e.seed(s) not supported.
+
+  // [rand.req.eng] specifies the parameter as 'unsigned long long'
+  // e.discard(unsigned long long) is supported.
+  unsigned long long z = 1;  // NOLINT(runtime/int)
+  e.discard(z);
+}
+
+TEST(NonsecureURBGBase, SeedSeqConstructorIsValid) {
+  std::seed_seq seq;
+  ExampleNonsecureURBG rbg(seq);
+}
+
+TEST(NonsecureURBGBase, CompatibleWithDistributionUtils) {
+  ExampleNonsecureURBG rbg;
+
+  absl::Uniform(rbg, 0, 100);
+  absl::Uniform(rbg, 0.5, 0.7);
+  absl::Poisson<uint32_t>(rbg);
+  absl::Exponential<float>(rbg);
+}
+
+TEST(NonsecureURBGBase, CompatibleWithStdDistributions) {
+  ExampleNonsecureURBG rbg;
+
+  std::uniform_int_distribution<uint32_t>(0, 100)(rbg);
+  std::uniform_real_distribution<float>()(rbg);
+  std::bernoulli_distribution(0.2)(rbg);
+}
+
+TEST(NonsecureURBGBase, ConsecutiveDefaultInstancesYieldUniqueVariates) {
+  const size_t kNumSamples = 128;
+
+  ExampleNonsecureURBG rbg1;
+  ExampleNonsecureURBG rbg2;
+
+  for (size_t i = 0; i < kNumSamples; i++) {
+    EXPECT_NE(rbg1(), rbg2());
+  }
+}
+
+TEST(NonsecureURBGBase, EqualSeedSequencesYieldEqualVariates) {
+  std::seed_seq seq;
+
+  ExampleNonsecureURBG rbg1(seq);
+  ExampleNonsecureURBG rbg2(seq);
+
+  // ExampleNonsecureURBG rbg3({1, 2, 3});  // Should not compile.
+
+  for (uint32_t i = 0; i < 1000; i++) {
+    EXPECT_EQ(rbg1(), rbg2());
+  }
+
+  rbg1.discard(100);
+  rbg2.discard(100);
+
+  // The sequences should continue after discarding
+  for (uint32_t i = 0; i < 1000; i++) {
+    EXPECT_EQ(rbg1(), rbg2());
+  }
+}
+
+// This is a PRNG-compatible type specifically designed to test
+// that NonsecureURBGBase::Seeder can correctly handle iterators
+// to arbitrary non-uint32_t size types.
+template <typename T>
+struct SeederTestEngine {
+  using result_type = T;
+
+  static constexpr result_type(min)() {
+    return (std::numeric_limits<result_type>::min)();
+  }
+  static constexpr result_type(max)() {
+    return (std::numeric_limits<result_type>::max)();
+  }
+
+  template <class SeedSequence,
+            typename = typename absl::enable_if_t<
+                !std::is_same<SeedSequence, SeederTestEngine>::value>>
+  explicit SeederTestEngine(SeedSequence&& seq) {
+    seed(seq);
+  }
+
+  SeederTestEngine(const SeederTestEngine&) = default;
+  SeederTestEngine& operator=(const SeederTestEngine&) = default;
+  SeederTestEngine(SeederTestEngine&&) = default;
+  SeederTestEngine& operator=(SeederTestEngine&&) = default;
+
+  result_type operator()() { return state[0]; }
+
+  template <class SeedSequence>
+  void seed(SeedSequence&& seq) {
+    std::fill(std::begin(state), std::end(state), T(0));
+    seq.generate(std::begin(state), std::end(state));
+  }
+
+  T state[2];
+};
+
+TEST(NonsecureURBGBase, SeederWorksForU32) {
+  using U32 =
+      absl::random_internal::NonsecureURBGBase<SeederTestEngine<uint32_t>>;
+  U32 x;
+  EXPECT_NE(0, x());
+}
+
+TEST(NonsecureURBGBase, SeederWorksForU64) {
+  using U64 =
+      absl::random_internal::NonsecureURBGBase<SeederTestEngine<uint64_t>>;
+
+  U64 x;
+  EXPECT_NE(0, x());
+}