chore: import upstream snapshot with attribution

test/cpp/phi/kernels/test_strings_copy_dev_api.cu

@@ -0,0 +1,73 @@
+/* Copyright (c) 2022 PaddlePaddle Authors. All Rights Reserved.
+
+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
+
+    http://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 <gtest/gtest.h>
+
+#include <algorithm>
+#include <memory>
+#include <string>
+
+#include "paddle/phi/api/lib/utils/allocator.h"
+#include "paddle/phi/backends/context_pool.h"
+#include "paddle/phi/common/pstring.h"
+#include "paddle/phi/core/string_tensor.h"
+#include "paddle/phi/kernels/strings/strings_copy_kernel.h"
+#include "paddle/phi/kernels/strings/strings_empty_kernel.h"
+
+namespace phi {
+namespace tests {
+
+using DDim = phi::DDim;
+using pstring = phi::dtype::pstring;
+
+TEST(DEV_API, strings_copy) {
+  // 1. create tensor
+  const DDim dims({2, 3});
+  StringTensorMeta meta(dims);
+
+  phi::DeviceContextPool& pool = phi::DeviceContextPool::Instance();
+
+  auto* dev_ctx = reinterpret_cast<phi::CPUContext*>(pool.Get(phi::CPUPlace()));
+  auto* gpu_dev_ctx =
+      reinterpret_cast<phi::GPUContext*>(pool.Get(phi::GPUPlace()));
+
+  StringTensor string_src = phi::strings::Empty(*dev_ctx, std::move(meta));
+  StringTensor string_dst = phi::strings::Empty(*dev_ctx, std::move(meta));
+  // 2. Assign input text
+  const char* input[] = {"A Short Pstring.",
+                         "A Large Pstring Whose Length Is Longer Than 22.",
+                         "abc",
+                         "defg",
+                         "hijklmn",
+                         "opqrst"};
+  pstring* string_src_data = dev_ctx->template Alloc<pstring>(&string_src);
+  for (int i = 0; i < string_src.numel(); ++i) {
+    string_src_data[i] = input[i];
+  }
+  StringTensor string_gpu1 = phi::strings::Empty(*gpu_dev_ctx, std::move(meta));
+  StringTensor string_gpu2 = phi::strings::Empty(*gpu_dev_ctx, std::move(meta));
+
+  // cpu->gpu
+  phi::strings::Copy(*gpu_dev_ctx, string_src, false, &string_gpu1);
+  // gpu->gpu
+  phi::strings::Copy(*gpu_dev_ctx, string_gpu1, false, &string_gpu2);
+  // gpu->cpu
+  phi::strings::Copy(*gpu_dev_ctx, string_gpu2, false, &string_dst);
+  for (int64_t i = 0; i < string_src.numel(); i++) {
+    ASSERT_EQ(string_src.data()[i], string_dst.data()[i]);
+  }
+}
+
+}  // namespace tests
+}  // namespace phi