Add a test for ranges::contains

Author: akukanov

test/parallel_api/ranges/std_ranges_contains.pass.cpp

@@ -0,0 +1,45 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// Copyright (C) 2026 UXL Foundation Contributors
+//
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "std_ranges_test.h"
+
+#if _ENABLE_STD_RANGES_TESTING
+#if __cpp_lib_ranges_contains >= 202207L
+    auto contains_checker = TEST_PREPARE_CALLABLE(std::ranges::contains);
+#else
+    struct {
+        template<std::ranges::input_range R, typename V, typename Proj = std::identity>
+        bool operator()(R&& r, V value, Proj proj = {})
+        {
+            auto last = std::ranges::end(r);
+            return std::ranges::find(std::ranges::begin(r), last, value, proj) != last;
+        }
+    } contains_checker;
+#endif
+#endif
+
+std::int32_t
+main()
+{
+#if _ENABLE_STD_RANGES_TESTING
+    using namespace test_std_ranges;
+    namespace dpl_ranges = oneapi::dpl::ranges;
+
+    // expected to be found
+    test_range_algo<0>{big_sz}(dpl_ranges::contains, contains_checker, small_size - 19);
+    test_range_algo<1>{}(dpl_ranges::contains, contains_checker, proj(small_size/2 + 28), proj);
+    test_range_algo<2, P2>{}(dpl_ranges::contains, contains_checker, 137, &P2::x);
+
+    // expected to be absent
+    test_range_algo<3, P2>{}(dpl_ranges::contains, contains_checker, -27, &P2::proj);
+    test_range_algo<4>{big_sz}(dpl_ranges::contains, contains_checker, -43);
+#endif //_ENABLE_STD_RANGES_TESTING
+
+    return TestUtils::done(_ENABLE_STD_RANGES_TESTING);
+}