diff --git a/libcxx/test/std/algorithms/ranges_robust_against_nonbool_predicates.pass.cpp b/libcxx/test/std/algorithms/ranges_robust_against_nonbool_predicates.pass.cpp
new file mode 100644
--- /dev/null
+++ b/libcxx/test/std/algorithms/ranges_robust_against_nonbool_predicates.pass.cpp
@@ -0,0 +1,179 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17
+// UNSUPPORTED: libcpp-has-no-incomplete-ranges
+
+// <algorithm>
+//
+// Range algorithms that take predicates should support predicates that return a non-boolean value as long as the
+// returned type is implicitly convertible to bool.
+
+#include <algorithm>
+
+#include <array>
+#include <concepts>
+#include <initializer_list>
+#include "boolean_testable.h"
+
+auto unary_pred = [](int i) { return BooleanTestable(i > 0); };
+static_assert(!std::same_as<decltype(unary_pred(1)), bool>);
+static_assert(std::convertible_to<decltype(unary_pred(1)), bool>);
+
+auto binary_pred = [](int i, int j) { return BooleanTestable(i < j); };
+static_assert(!std::same_as<decltype(binary_pred(1, 2)), bool>);
+static_assert(std::convertible_to<decltype(binary_pred(1, 2)), bool>);
+
+// (in, pred)
+template <class Func, std::ranges::range Input, class Pred>
+void test(Func&& func, Input& in, Pred& pred) {
+  func(in.begin(), in.end(), pred);
+  func(in, pred);
+}
+
+// (in1, in2, pred)
+template <class Func, std::ranges::range Input, class Pred>
+void test(Func&& func, Input& in1, Input& in2, Pred& pred) {
+  func(in1.begin(), in1.end(), in2.begin(), in2.end(), pred);
+  func(in1, in2, pred);
+}
+
+// (in, out, pred)
+template <class Func, std::ranges::range Input, std::weakly_incrementable Output, class Pred>
+void test(Func&& func, Input& in, Output& out, Pred& pred) {
+  func(in.begin(), in.end(), out, pred);
+  func(in, out, pred);
+}
+
+// (in, mid, pred)
+// To avoid ambiguity with the `(in, out, pred)` overload, this function has a different name.
+template <class Func, std::ranges::range Input, class Pred>
+void test_mid(Func&& func, Input& in, std::ranges::iterator_t<Input>& mid, Pred& pred) {
+  func(in.begin(), mid, in.end(), pred);
+  func(in, mid, pred);
+}
+
+// (in1, in2, out, pred)
+template <class Func, std::ranges::range Input, std::weakly_incrementable Output, class Pred>
+void test(Func&& func, Input& in1, Input& in2, Output& out, Pred& pred) {
+  func(in1.begin(), in1.end(), in2.begin(), in2.end(), out, pred);
+  func(in1, in2, out, pred);
+}
+
+// (in, out1, out2, pred)
+template <class Func, std::ranges::range Input, std::weakly_incrementable Output, class Pred>
+void test(Func&& func, Input& in, Output& out1, Output& out2, Pred& pred) {
+  func(in.begin(), in.end(), out1, out2, pred);
+  func(in, out1, out2, pred);
+}
+
+// (in, val, pred)
+template <class Func, std::ranges::range Input, class T, class Pred>
+void test(Func&& func, Input& in, T& value, Pred& pred) {
+  func(in.begin(), in.end(), value, pred);
+  func(in, value, pred);
+}
+
+void test_all() {
+  // TODO(ranges): uncomment test cases as range algorithms are implemented.
+
+  std::array in = {1, 2, 3};
+  std::array in2 = {4, 5, 6};
+  auto mid = in.begin() + 1;
+
+  std::array output = {4, 5, 6};
+  auto out = output.begin();
+  //auto out2 = output.begin() + 1;
+
+  int x = 2;
+  //int count = 1;
+
+  test(std::ranges::any_of, in, unary_pred);
+  test(std::ranges::all_of, in, unary_pred);
+  test(std::ranges::none_of, in, unary_pred);
+  test(std::ranges::find_if, in, unary_pred);
+  test(std::ranges::find_if_not, in, unary_pred);
+  test(std::ranges::find_first_of, in, in2, binary_pred);
+  test(std::ranges::adjacent_find, in, binary_pred);
+  test(std::ranges::mismatch, in, in2, binary_pred);
+  test(std::ranges::equal, in, in2, binary_pred);
+  test(std::ranges::lexicographical_compare, in, in2, binary_pred);
+  //test(std::ranges::partition_point, unary_pred);
+  test(std::ranges::lower_bound, in, x, binary_pred);
+  test(std::ranges::upper_bound, in, x, binary_pred);
+  //test(std::ranges::equal_range, in, x, binary_pred);
+  test(std::ranges::binary_search, in, x, binary_pred);
+
+  // min
+  std::ranges::min(1, 2, binary_pred);
+  std::ranges::min(std::initializer_list<int>{1, 2}, binary_pred);
+  std::ranges::min(in, binary_pred);
+  // max
+  std::ranges::max(1, 2, binary_pred);
+  std::ranges::max(std::initializer_list<int>{1, 2}, binary_pred);
+  std::ranges::max(in, binary_pred);
+  // minmax
+  std::ranges::minmax(1, 2, binary_pred);
+  std::ranges::minmax(std::initializer_list<int>{1, 2}, binary_pred);
+  std::ranges::minmax(in, binary_pred);
+
+  test(std::ranges::min_element, in, binary_pred);
+  test(std::ranges::max_element, in, binary_pred);
+  test(std::ranges::minmax_element, in, binary_pred);
+  test(std::ranges::count_if, in, unary_pred);
+  //test(std::ranges::search, in, in2, binary_pred);
+  //test(std::ranges::search_n, in, count, binary_pred);
+  //test(std::ranges::find_end, in, in2, binary_pred);
+  test(std::ranges::is_partitioned, in, unary_pred);
+  test(std::ranges::is_sorted, in, binary_pred);
+  test(std::ranges::is_sorted_until, in, binary_pred);
+  //test(std::ranges::includes, in, in2, binary_pred);
+  //test(std::ranges::is_heap, in, binary_pred);
+  //test(std::ranges::is_heap_until, in, binary_pred);
+  //std::ranges::clamp(2, 1, 3, binary_pred);
+  //test(std::ranges::is_permutation, in, in2, binary_pred);
+  test(std::ranges::copy_if, in, out, unary_pred);
+  //test(std::ranges::remove_copy_if, in, out, unary_pred);
+
+  // replace_if
+  //std::ranges::replace_if(in.begin(), in.end(), unary_pred, x);
+  //std::ranges::replace_if(in, unary_pred, x);
+  // replace_copy_if
+  //std::ranges::replace_copy_if(in.begin(), in.end(), out, unary_pred, x);
+  //std::ranges::replace_copy_if(in, out, unary_pred, x);
+
+  //test(std::ranges::unique_copy, in, out, unary_pred);
+  //test(std::ranges::partition_copy, in, out, out2, unary_pred);
+  //test(std::ranges::partial_sort_copy, in, in2, binary_pred);
+  test(std::ranges::merge, in, in2, out, binary_pred);
+  test(std::ranges::set_difference, in, in2, out, binary_pred);
+  //test(std::ranges::set_intersection, in, in2, out, binary_pred);
+  //test(std::ranges::set_symmetric_difference, in, in2, out, binary_pred);
+  //test(std::ranges::set_union, in, in2, out, binary_pred);
+  test(std::ranges::remove_if, in, unary_pred);
+  //test(std::ranges::unique, in, binary_pred);
+  //test(std::ranges::partition, in, binary_pred);
+  //test(std::ranges::stable_partition, in, binary_pred);
+  //test(std::ranges::sort, in, binary_pred);
+  //test(std::ranges::stable_sort, in, binary_pred);
+  //test_mid(std::ranges::partial_sort, in, mid, binary_pred);
+  test_mid(std::ranges::nth_element, in, mid, binary_pred);
+  //test_mid(std::ranges::inplace_merge, in, mid, binary_pred);
+  test(std::ranges::make_heap, in, binary_pred);
+  test(std::ranges::push_heap, in, binary_pred);
+  test(std::ranges::pop_heap, in, binary_pred);
+  test(std::ranges::sort_heap, in, binary_pred);
+  //test(std::ranges::prev_permutation, in, binary_pred);
+  //test(std::ranges::next_permutation, in, binary_pred);
+}
+
+int main(int, char**) {
+  test_all();
+
+  return 0;
+}