From 986bd021d433d81a085a0c8250e1fe57e986bc20 Mon Sep 17 00:00:00 2001
From: Sam Cunliffe <s.cunliffe@ucl.ac.uk>
Date: Fri, 12 May 2023 15:28:27 +0100
Subject: [PATCH] Add a checker for the existence of a H5::Group in the file.

Co-authored-by: willGraham01 <willGraham01@users.noreply.github.com>
---
 tdms/include/hdf5_io/hdf5_base.h               | 15 ++++++++++++++-
 tdms/src/hdf5_io/hdf5_base.cpp                 | 10 ----------
 tdms/tests/unit/hdf5_io_tests/test_hdf5_io.cpp |  7 +++++++
 3 files changed, 21 insertions(+), 11 deletions(-)

diff --git a/tdms/include/hdf5_io/hdf5_base.h b/tdms/include/hdf5_io/hdf5_base.h
index 188bb8476..0d7e2e127 100644
--- a/tdms/include/hdf5_io/hdf5_base.h
+++ b/tdms/include/hdf5_io/hdf5_base.h
@@ -12,7 +12,6 @@
 
 #include <H5Cpp.h>
 
-#include "cell_coordinate.h"
 #include "hdf5_io/hdf5_dimension.h"
 
 /**
@@ -90,4 +89,18 @@ class HDF5Base {
    * @return false Otherwise.
    */
   bool is_ok() const;
+
+  /**
+   * @brief Checks if the group `group_name` exists in this file.
+   *
+   * @details Just wraps some ugly H5Lexists call from the C-API.
+   *          TODO: does this work if given 'group/subgroup' ?
+   *
+   * @param group_name Name of the group under root to search for
+   * @return true The group is present in the file, under root
+   * @return false Otherwise
+   */
+  bool group_exists(const std::string &group_name) const {
+    return H5Lexists(file_->getId(), group_name.c_str(), H5P_DEFAULT) > 0;
+  };
 };
diff --git a/tdms/src/hdf5_io/hdf5_base.cpp b/tdms/src/hdf5_io/hdf5_base.cpp
index d07a957e1..19b916b2c 100644
--- a/tdms/src/hdf5_io/hdf5_base.cpp
+++ b/tdms/src/hdf5_io/hdf5_base.cpp
@@ -13,16 +13,6 @@
 
 using namespace std;
 
-ijk to_ijk(const std::vector<hsize_t> dimensions) {
-  unsigned int rank = dimensions.size();
-  ijk out;
-  if (rank > 0) out.i = (int) dimensions[0];
-  if (rank > 1) out.j = (int) dimensions[1];
-  if (rank > 2) out.k = (int) dimensions[2];
-  if (rank > 3) spdlog::warn("Rank > 3");
-  return out;
-}
-
 vector<string> HDF5Base::get_datanames() const {
   vector<string> names;
 
diff --git a/tdms/tests/unit/hdf5_io_tests/test_hdf5_io.cpp b/tdms/tests/unit/hdf5_io_tests/test_hdf5_io.cpp
index 031b4c472..066a47e0e 100644
--- a/tdms/tests/unit/hdf5_io_tests/test_hdf5_io.cpp
+++ b/tdms/tests/unit/hdf5_io_tests/test_hdf5_io.cpp
@@ -19,6 +19,7 @@
 
 using namespace std;
 using tdms_tests::create_tmp_dir;
+using tdms_unit_test_data::struct_testdata;
 
 TEST_CASE("Test file I/O construction/destruction.") {
   // test-case wide setup - temporary directory
@@ -148,3 +149,9 @@ TEST_CASE("Test read/write wrt standard datatypes") {
   SPDLOG_DEBUG("Removing temporary directory.");
   filesystem::remove_all(tmp);
 }
+
+TEST_CASE("Test group can be found") {
+  HDF5Reader reader(struct_testdata);
+  REQUIRE(!reader.group_exists("group_doesnt_exist"));
+  REQUIRE(reader.group_exists("example_struct"));
+}