Merge pull request #114 from TGSAI/106_flattened_warning

Resolve warning regarding sizeof(void)

Author: blasscoc

mdio/variable.h

@@ -1726,18 +1726,16 @@ struct VariableData {
    * @endcode
    */
   ptrdiff_t get_flattened_offset() {
-    // TODO(BrianMichell): Implement unit test
     auto accessor = get_data_accessor();
-    auto origin_ptr =
-        accessor.data();  // The raw pointer to the data. May not start at 0.
-    auto offset_ptr =
-        accessor.byte_strided_origin_pointer();  // The raw pointer to the first
-                                                 // element of the data.
+    // The raw pointer to the data. May not start at 0.
+    auto origin_ptr = accessor.data();
+    // The raw pointer to the first element of the data.
+    auto offset_ptr = accessor.byte_strided_origin_pointer();
     char* origin_addr = reinterpret_cast<char*>(origin_ptr);
-    char* offset_addr = reinterpret_cast<char*>(
-        offset_ptr.get());  // We have to get the raw pointer
+    // We have to get the raw pointer
+    char* offset_addr = reinterpret_cast<char*>(offset_ptr.get());
     ptrdiff_t byte_diff = offset_addr - origin_addr;
-    return byte_diff / sizeof(T);
+    return byte_diff / dtype().size();
   }
 
   // An identifier for the variable.

mdio/variable_test.cc

@@ -1054,6 +1054,25 @@ TEST(VariableData, writeChunkedData) {
   std::filesystem::remove_all("name");
 }
 
+TEST(VariableData, flattenedOffset) {
+  auto json = PopulateStore(json_good).value();
+  auto variableObject = mdio::Variable<>::Open(json).result();
+  EXPECT_TRUE(variableObject.ok());
+
+  mdio::RangeDescriptor<mdio::Index> desc1 = {"x", 50, 100, 1};
+  mdio::RangeDescriptor<mdio::Index> desc2 = {"y", 0, 100, 1};
+  variableObject = variableObject.value().slice(desc1, desc2);
+
+  auto variableDataFuture = variableObject->Read();
+
+  auto variableDataObject = variableDataFuture.result();
+  EXPECT_TRUE(variableDataObject.ok());
+
+  auto varData = variableDataObject.value();
+
+  EXPECT_EQ(varData.get_flattened_offset(), 5000);
+}
+
 TEST(VariableData, inMemoryEdits) {
   auto json = PopulateStore(json_good).value();
   auto variableObject = mdio::Variable<>::Open(json).result();