Merge new upstream LTS 20240722.0

4 files changed, 124 insertions, 18 deletions

diff --git a/absl/algorithm/BUILD.bazel b/absl/algorithm/BUILD.bazel
index ddf9e11f..f20e7290 100644
--- a/absl/algorithm/BUILD.bazel
+++ b/absl/algorithm/BUILD.bazel
@@ -65,6 +65,7 @@ cc_library(
     linkopts = ABSL_DEFAULT_LINKOPTS,
     deps = [
         ":algorithm",
+        "//absl/base:config",
         "//absl/base:core_headers",
         "//absl/base:nullability",
         "//absl/meta:type_traits",
@@ -79,6 +80,7 @@ cc_test(
     deps = [
         ":container",
         "//absl/base",
+        "//absl/base:config",
         "//absl/base:core_headers",
         "//absl/memory",
         "//absl/types:span",
diff --git a/absl/algorithm/CMakeLists.txt b/absl/algorithm/CMakeLists.txt
index 5577164d..252b6b20 100644
--- a/absl/algorithm/CMakeLists.txt
+++ b/absl/algorithm/CMakeLists.txt
@@ -48,6 +48,7 @@ absl_cc_library(
     ${ABSL_DEFAULT_COPTS}
   DEPS
     absl::algorithm
+    absl::config
     absl::core_headers
     absl::meta
     absl::nullability
@@ -64,6 +65,7 @@ absl_cc_test(
   DEPS
     absl::algorithm_container
     absl::base
+    absl::config
     absl::core_headers
     absl::memory
     absl::span
diff --git a/absl/algorithm/container.h b/absl/algorithm/container.h
index c7bafae1..6bbe3b5a 100644
--- a/absl/algorithm/container.h
+++ b/absl/algorithm/container.h
@@ -44,6 +44,7 @@
 #include <cassert>
 #include <iterator>
 #include <numeric>
+#include <random>
 #include <type_traits>
 #include <unordered_map>
 #include <unordered_set>
@@ -51,6 +52,7 @@
 #include <vector>
 
 #include "absl/algorithm/algorithm.h"
+#include "absl/base/config.h"
 #include "absl/base/macros.h"
 #include "absl/base/nullability.h"
 #include "absl/meta/type_traits.h"
@@ -92,17 +94,17 @@ using ContainerPointerType =
 //   using std::end;
 //   std::foo(begin(c), end(c));
 // becomes
-//   std::foo(container_algorithm_internal::begin(c),
-//            container_algorithm_internal::end(c));
+//   std::foo(container_algorithm_internal::c_begin(c),
+//            container_algorithm_internal::c_end(c));
 // These are meant for internal use only.
 
 template <typename C>
-ContainerIter<C> c_begin(C& c) {
+ABSL_INTERNAL_CONSTEXPR_SINCE_CXX17 ContainerIter<C> c_begin(C& c) {
   return begin(c);
 }
 
 template <typename C>
-ContainerIter<C> c_end(C& c) {
+ABSL_INTERNAL_CONSTEXPR_SINCE_CXX17 ContainerIter<C> c_end(C& c) {
   return end(c);
 }
 
@@ -145,8 +147,9 @@ bool c_linear_search(const C& c, EqualityComparable&& value) {
 // Container-based version of the <iterator> `std::distance()` function to
 // return the number of elements within a container.
 template <typename C>
-container_algorithm_internal::ContainerDifferenceType<const C> c_distance(
-    const C& c) {
+ABSL_INTERNAL_CONSTEXPR_SINCE_CXX17
+    container_algorithm_internal::ContainerDifferenceType<const C>
+    c_distance(const C& c) {
   return std::distance(container_algorithm_internal::c_begin(c),
                        container_algorithm_internal::c_end(c));
 }
@@ -210,6 +213,16 @@ container_algorithm_internal::ContainerIter<C> c_find(C& c, T&& value) {
                    std::forward<T>(value));
 }
 
+// c_contains()
+//
+// Container-based version of the <algorithm> `std::ranges::contains()` C++23
+// function to search a container for a value.
+template <typename Sequence, typename T>
+bool c_contains(const Sequence& sequence, T&& value) {
+  return absl::c_find(sequence, std::forward<T>(value)) !=
+         container_algorithm_internal::c_end(sequence);
+}
+
 // c_find_if()
 //
 // Container-based version of the <algorithm> `std::find_if()` function to find
@@ -426,6 +439,26 @@ container_algorithm_internal::ContainerIter<Sequence1> c_search(
                      std::forward<BinaryPredicate>(pred));
 }
 
+// c_contains_subrange()
+//
+// Container-based version of the <algorithm> `std::ranges::contains_subrange()`
+// C++23 function to search a container for a subsequence.
+template <typename Sequence1, typename Sequence2>
+bool c_contains_subrange(Sequence1& sequence, Sequence2& subsequence) {
+  return absl::c_search(sequence, subsequence) !=
+         container_algorithm_internal::c_end(sequence);
+}
+
+// Overload of c_contains_subrange() for using a predicate evaluation other than
+// `==` as the function's test condition.
+template <typename Sequence1, typename Sequence2, typename BinaryPredicate>
+bool c_contains_subrange(Sequence1& sequence, Sequence2& subsequence,
+                         BinaryPredicate&& pred) {
+  return absl::c_search(sequence, subsequence,
+                        std::forward<BinaryPredicate>(pred)) !=
+         container_algorithm_internal::c_end(sequence);
+}
+
 // c_search_n()
 //
 // Container-based version of the <algorithm> `std::search_n()` function to
@@ -1500,8 +1533,9 @@ c_is_heap_until(RandomAccessContainer& sequence, LessThan&& comp) {
 // to return an iterator pointing to the element with the smallest value, using
 // `operator<` to make the comparisons.
 template <typename Sequence>
-container_algorithm_internal::ContainerIter<Sequence> c_min_element(
-    Sequence& sequence) {
+ABSL_INTERNAL_CONSTEXPR_SINCE_CXX17
+    container_algorithm_internal::ContainerIter<Sequence>
+    c_min_element(Sequence& sequence) {
   return std::min_element(container_algorithm_internal::c_begin(sequence),
                           container_algorithm_internal::c_end(sequence));
 }
@@ -1509,8 +1543,9 @@ container_algorithm_internal::ContainerIter<Sequence> c_min_element(
 // Overload of c_min_element() for performing a `comp` comparison other than
 // `operator<`.
 template <typename Sequence, typename LessThan>
-container_algorithm_internal::ContainerIter<Sequence> c_min_element(
-    Sequence& sequence, LessThan&& comp) {
+ABSL_INTERNAL_CONSTEXPR_SINCE_CXX17
+    container_algorithm_internal::ContainerIter<Sequence>
+    c_min_element(Sequence& sequence, LessThan&& comp) {
   return std::min_element(container_algorithm_internal::c_begin(sequence),
                           container_algorithm_internal::c_end(sequence),
                           std::forward<LessThan>(comp));
@@ -1522,8 +1557,9 @@ container_algorithm_internal::ContainerIter<Sequence> c_min_element(
 // to return an iterator pointing to the element with the largest value, using
 // `operator<` to make the comparisons.
 template <typename Sequence>
-container_algorithm_internal::ContainerIter<Sequence> c_max_element(
-    Sequence& sequence) {
+ABSL_INTERNAL_CONSTEXPR_SINCE_CXX17
+    container_algorithm_internal::ContainerIter<Sequence>
+    c_max_element(Sequence& sequence) {
   return std::max_element(container_algorithm_internal::c_begin(sequence),
                           container_algorithm_internal::c_end(sequence));
 }
@@ -1531,8 +1567,9 @@ container_algorithm_internal::ContainerIter<Sequence> c_max_element(
 // Overload of c_max_element() for performing a `comp` comparison other than
 // `operator<`.
 template <typename Sequence, typename LessThan>
-container_algorithm_internal::ContainerIter<Sequence> c_max_element(
-    Sequence& sequence, LessThan&& comp) {
+ABSL_INTERNAL_CONSTEXPR_SINCE_CXX17
+    container_algorithm_internal::ContainerIter<Sequence>
+    c_max_element(Sequence& sequence, LessThan&& comp) {
   return std::max_element(container_algorithm_internal::c_begin(sequence),
                           container_algorithm_internal::c_end(sequence),
                           std::forward<LessThan>(comp));
@@ -1545,8 +1582,9 @@ container_algorithm_internal::ContainerIter<Sequence> c_max_element(
 // smallest and largest values, respectively, using `operator<` to make the
 // comparisons.
 template <typename C>
-container_algorithm_internal::ContainerIterPairType<C, C> c_minmax_element(
-    C& c) {
+ABSL_INTERNAL_CONSTEXPR_SINCE_CXX17
+    container_algorithm_internal::ContainerIterPairType<C, C>
+    c_minmax_element(C& c) {
   return std::minmax_element(container_algorithm_internal::c_begin(c),
                              container_algorithm_internal::c_end(c));
 }
@@ -1554,8 +1592,9 @@ container_algorithm_internal::ContainerIterPairType<C, C> c_minmax_element(
 // Overload of c_minmax_element() for performing `comp` comparisons other than
 // `operator<`.
 template <typename C, typename LessThan>
-container_algorithm_internal::ContainerIterPairType<C, C> c_minmax_element(
-    C& c, LessThan&& comp) {
+ABSL_INTERNAL_CONSTEXPR_SINCE_CXX17
+    container_algorithm_internal::ContainerIterPairType<C, C>
+    c_minmax_element(C& c, LessThan&& comp) {
   return std::minmax_element(container_algorithm_internal::c_begin(c),
                              container_algorithm_internal::c_end(c),
                              std::forward<LessThan>(comp));
diff --git a/absl/algorithm/container_test.cc b/absl/algorithm/container_test.cc
index c01f5fc0..50122249 100644
--- a/absl/algorithm/container_test.cc
+++ b/absl/algorithm/container_test.cc
@@ -15,6 +15,7 @@
 #include "absl/algorithm/container.h"
 
 #include <algorithm>
+#include <array>
 #include <functional>
 #include <initializer_list>
 #include <iterator>
@@ -31,6 +32,7 @@
 #include "gmock/gmock.h"
 #include "gtest/gtest.h"
 #include "absl/base/casts.h"
+#include "absl/base/config.h"
 #include "absl/base/macros.h"
 #include "absl/memory/memory.h"
 #include "absl/types/span.h"
@@ -113,6 +115,11 @@ TEST_F(NonMutatingTest, FindReturnsCorrectType) {
   absl::c_find(absl::implicit_cast<const std::list<int>&>(sequence_), 3);
 }
 
+TEST_F(NonMutatingTest, Contains) {
+  EXPECT_TRUE(absl::c_contains(container_, 3));
+  EXPECT_FALSE(absl::c_contains(container_, 4));
+}
+
 TEST_F(NonMutatingTest, FindIf) { absl::c_find_if(container_, Predicate); }
 
 TEST_F(NonMutatingTest, FindIfNot) {
@@ -305,6 +312,17 @@ TEST_F(NonMutatingTest, SearchWithPredicate) {
   absl::c_search(vector_, sequence_, BinPredicate);
 }
 
+TEST_F(NonMutatingTest, ContainsSubrange) {
+  EXPECT_TRUE(absl::c_contains_subrange(sequence_, vector_));
+  EXPECT_TRUE(absl::c_contains_subrange(vector_, sequence_));
+  EXPECT_TRUE(absl::c_contains_subrange(array_, sequence_));
+}
+
+TEST_F(NonMutatingTest, ContainsSubrangeWithPredicate) {
+  EXPECT_TRUE(absl::c_contains_subrange(sequence_, vector_, Equals));
+  EXPECT_TRUE(absl::c_contains_subrange(vector_, sequence_, Equals));
+}
+
 TEST_F(NonMutatingTest, SearchN) { absl::c_search_n(sequence_, 3, 1); }
 
 TEST_F(NonMutatingTest, SearchNWithPredicate) {
@@ -1144,4 +1162,49 @@ TEST(MutatingTest, PermutationOperations) {
   EXPECT_EQ(initial, permuted);
 }
 
+#if defined(ABSL_INTERNAL_CPLUSPLUS_LANG) && \
+    ABSL_INTERNAL_CPLUSPLUS_LANG >= 201703L
+TEST(ConstexprTest, Distance) {
+  // Works at compile time with constexpr containers.
+  static_assert(absl::c_distance(std::array<int, 3>()) == 3);
+}
+
+TEST(ConstexprTest, MinElement) {
+  constexpr std::array<int, 3> kArray = {1, 2, 3};
+  static_assert(*absl::c_min_element(kArray) == 1);
+}
+
+TEST(ConstexprTest, MinElementWithPredicate) {
+  constexpr std::array<int, 3> kArray = {1, 2, 3};
+  static_assert(*absl::c_min_element(kArray, std::greater<int>()) == 3);
+}
+
+TEST(ConstexprTest, MaxElement) {
+  constexpr std::array<int, 3> kArray = {1, 2, 3};
+  static_assert(*absl::c_max_element(kArray) == 3);
+}
+
+TEST(ConstexprTest, MaxElementWithPredicate) {
+  constexpr std::array<int, 3> kArray = {1, 2, 3};
+  static_assert(*absl::c_max_element(kArray, std::greater<int>()) == 1);
+}
+
+TEST(ConstexprTest, MinMaxElement) {
+  static constexpr std::array<int, 3> kArray = {1, 2, 3};
+  constexpr auto kMinMaxPair = absl::c_minmax_element(kArray);
+  static_assert(*kMinMaxPair.first == 1);
+  static_assert(*kMinMaxPair.second == 3);
+}
+
+TEST(ConstexprTest, MinMaxElementWithPredicate) {
+  static constexpr std::array<int, 3> kArray = {1, 2, 3};
+  constexpr auto kMinMaxPair =
+      absl::c_minmax_element(kArray, std::greater<int>());
+  static_assert(*kMinMaxPair.first == 3);
+  static_assert(*kMinMaxPair.second == 1);
+}
+
+#endif  // defined(ABSL_INTERNAL_CPLUSPLUS_LANG) &&
+        //  ABSL_INTERNAL_CPLUSPLUS_LANG >= 201703L
+
 }  // namespace