Add unit test for h5 filewriter

tests/CMakeLists.txt

@@ -5,7 +5,11 @@ target_link_libraries(test_make_models GTest::gtest_main dx2 Eigen3::Eigen nlohm
 add_executable(test_read_h5_array test_read_h5_array.cxx)
 target_link_libraries(test_read_h5_array GTest::gtest_main dx2 hdf5::hdf5)
 
+add_executable(test_write_h5_array test_write_h5_array.cxx)
+target_link_libraries(test_write_h5_array GTest::gtest_main dx2 hdf5::hdf5)
+
 include(GoogleTest)
 
 gtest_discover_tests(test_make_models PROPERTIES LABELS dx2tests)
 gtest_discover_tests(test_read_h5_array WORKING_DIRECTORY "${PROJECT_SOURCE_DIR}/tests" PROPERTIES LABELS dx2tests)
+gtest_discover_tests(test_write_h5_array WORKING_DIRECTORY "${PROJECT_SOURCE_DIR}/tests" PROPERTIES LABELS dx2tests)

tests/test_write_h5_array.cxx

@@ -0,0 +1,43 @@
+#include <filesystem>
+#include <gtest/gtest.h>
+#include <h5/h5read_processed.h>
+#include <h5/h5write.h>
+#include <vector>
+
+// Test writing a 3D vector dataset to an HDF5 file and verifying the written
+// content
+TEST(ExampleTests, WriteArrayTest) {
+  // Define the test file path
+  std::filesystem::path cwd = std::filesystem::current_path();
+  std::string test_file_path = cwd.generic_string();
+  test_file_path.append("/data/test_write.h5");
+
+  // Prepare test data (3D vectors)
+  std::vector<std::array<double, 3>> xyzobs_test_data = {
+      {100.1, 200.2, 300.3}, {400.4, 500.5, 600.6}, {700.7, 800.8, 900.9}};
+
+  // Call the function to write the test data to the HDF5 file
+  std::string dataset_name = "xyzobs.px.value";
+  std::string group_path = "processing";
+
+  write_xyzobs_to_h5_file(test_file_path, group_path, dataset_name,
+                          xyzobs_test_data);
+
+  // Read the written data back from the HDF5 file
+  std::string full_dataset_path = "/dials/processing/group_0/xyzobs.px.value";
+  std::vector<double> read_xyzobs =
+      read_array_from_h5_file<double>(test_file_path, full_dataset_path);
+
+  // Validate the size of the read data
+  ASSERT_EQ(read_xyzobs.size(), xyzobs_test_data.size() * 3);
+
+  // Validate the content of the read data
+  for (std::size_t i = 0; i < xyzobs_test_data.size(); ++i) {
+    EXPECT_DOUBLE_EQ(read_xyzobs[i * 3 + 0], xyzobs_test_data[i][0]);
+    EXPECT_DOUBLE_EQ(read_xyzobs[i * 3 + 1], xyzobs_test_data[i][1]);
+    EXPECT_DOUBLE_EQ(read_xyzobs[i * 3 + 2], xyzobs_test_data[i][2]);
+  }
+
+  // Clean up test file after successful run (comment out to keep the test file)
+  std::filesystem::remove(test_file_path);
+}