Update params for KernelConfig and add basic tests for getThreadId

tests/cuda_unit_tests/CMakeLists.txt

@@ -3,6 +3,7 @@ include_directories(${gtest_SOURCE_DIR}/include ${gtest_SOURCE_DIR})
 add_executable(${NAME}_cuda_tests
     test_potential.cu
     test_forces.cu
+    test_kernel_config.cu
 )
 
 target_link_libraries(${NAME}_cuda_tests gtest gtest_main)

tests/cuda_unit_tests/test_kernel_config.cu

@@ -0,0 +1,48 @@
+
+#include "kernel_config.cuh"
+#include <cuda_runtime.h>
+#include <gtest/gtest.h>
+#include <numeric>
+#include <vector>
+
+// Kernel to test the get_thread_id() function
+__global__ void test_get_thread_id_kernel(size_t *output, size_t n_elements) {
+  size_t i = get_thread_id();
+  if (i < n_elements) {
+    output[i] = i;
+  }
+}
+
+// Test fixture for kernel config tests
+class KernelConfigTest : public ::testing::Test {
+protected:
+  void SetUp() override {
+    // Set up any common resources for the tests
+  }
+
+  void TearDown() override {
+    // Clean up any resources
+  }
+};
+
+TEST_F(KernelConfigTest, GetThreadId) {
+  const size_t n_elements = 10000;
+  KernelConfig config = get_launch_config(n_elements);
+
+  size_t *d_output;
+  cudaMalloc(&d_output, n_elements * sizeof(size_t));
+
+  test_get_thread_id_kernel<<<config.blocks, config.threads>>>(d_output,
+                                                               n_elements);
+
+  std::vector<size_t> h_output(n_elements);
+  cudaMemcpy(h_output.data(), d_output, n_elements * sizeof(size_t),
+             cudaMemcpyDeviceToHost);
+
+  cudaFree(d_output);
+
+  std::vector<size_t> expected(n_elements);
+  std::iota(expected.begin(), expected.end(), 0);
+
+  ASSERT_EQ(h_output, expected);
+}