Fix generic type validation to support datetimes and non-ASCII strings. (#291)

* Throw `ArgumentException` on type mismatches.

* Fix and centralize generic type validation.

And also document which type is compatible with which `DataType`.

* Improve type checking for `FragmentInfo` methods when the type is string.

If the generic type is string, we check ourselves that the `DataType` is a string one. This ensures the exception thrown is `ArgumentException` instead of `TileDBException`.
The exception message also is more descriptive.

* Obsolete the converters between TileDB data types and .NET types.

* Use the correct obsoletion code in two cases.

The obsoletions in question have not yet shipped.

* Validate the data type in a couple more cases.

* Suppress obsoletion warning `TILEDB0013` in the `TileDB.CSharp` project.

Author: teo-tsirpanis

docs/obsoletions.md

@@ -7,7 +7,7 @@ Following [the deprecation policy of TileDB Embedded][core-deprecation], obsolet
 |Diagnostic codes|Deprecated in version|Removed in version|
 |----------------|---------------------|------------------|
 |[`TILEDB0001`](#TILEDB0001) …[`TILEDB0011`](#TILEDB0011)|5.3.0|5.5.0|
-|[`TILEDB0012`](#TILEDB0012) …[`TILEDB0012`](#TILEDB0012)|5.7.0|5.9.0|
+|[`TILEDB0012`](#TILEDB0012) …[`TILEDB0013`](#TILEDB0013)|5.7.0|5.9.0|
 
 ## `TILEDB0001` - Enum value names that start with `TILEDB_` were replaced with C#-friendly names.
 
@@ -320,3 +320,17 @@ The obsoleted APIs fall into the following categories:
 - Types with the name `tiledb_***_t` were made public again only to support the APIs of the safe handles above. They have little other use on their own. You should use APIs in the `TileDB.CSharp` namespace instead.
 
 [core-deprecation]: https://github.com/TileDB-Inc/TileDB/blob/dev/doc/policy/api_changes.md
+
+## `TILEDB0013` - The `EnumUtils.TypeToDataType` and `EnumUtils.DataTypeToType` methods are obsolete and will be removed in a future version.
+
+<a name="TILEDB0013"></a>
+
+The `EnumUtils.TypeToDataType` and `EnumUtils.DataTypeToType` methods convert between TileDB data types and .NET types. Given that there is no one-to-one correspondence between these two and for legacy reasons, these methods sometimes return wrong results and were obsoleted.
+
+### Version introduced
+
+5.7.0
+
+### Recommended action
+
+If you are performing queries on arrays of unknown schema, you can use the `Query.UnsafeSetDataBuffer` and `Query.UnsafeSetWriteDataBuffer` methods to set a data buffer to a query without type validation.

sources/TileDB.CSharp/Array.cs

@@ -501,15 +501,11 @@ static void GetDomain<T>(Array array, string dimName, uint i, NonEmptyDomain non
         /// <exception cref="ArgumentException"><typeparamref name="T"/> is not the dimension's type.</exception>
         public (T Start, T End, bool IsEmpty) NonEmptyDomain<T>(uint index) where T : struct
         {
-            var datatype = EnumUtil.TypeToDataType(typeof(T));
             using (var schema = Schema())
             using (var domain = schema.Domain())
             using (var dimension = domain.Dimension(index))
             {
-                if (datatype != dimension.Type())
-                {
-                    throw new ArgumentException("Array.NonEmptyDomain, not valid datatype!");
-                }
+                ErrorHandling.CheckDataType<T>(dimension.Type());
             }
 
             SequentialPair<T> data;
@@ -531,15 +527,11 @@ static void GetDomain<T>(Array array, string dimName, uint i, NonEmptyDomain non
         /// <exception cref="ArgumentException"><typeparamref name="T"/> is not the dimension's type.</exception>
         public (T Start, T End, bool IsEmpty) NonEmptyDomain<T>(string name) where T : struct
         {
-            var datatype = EnumUtil.TypeToDataType(typeof(T));
             using (var schema = Schema())
             using (var domain = schema.Domain())
             using (var dimension = domain.Dimension(name))
             {
-                if (datatype != dimension.Type())
-                {
-                    throw new ArgumentException("Array.NonEmptyDomain, not valid datatype!");
-                }
+                ErrorHandling.CheckDataType<T>(dimension.Type());
             }
 
             using var ms_name = new MarshaledString(name);

sources/TileDB.CSharp/ArrayMetadata.cs

@@ -300,7 +300,7 @@ IEnumerator IEnumerable.GetEnumerator()
 
         private void put_metadata<T>(string key, T[] value, tiledb_datatype_t tiledb_datatype) where T : struct
         {
-            ErrorHandling.ThrowIfManagedType<T>();
+            ErrorHandling.CheckDataType<T>((DataType)tiledb_datatype);
             if (string.IsNullOrEmpty(key) || value.Length == 0)
             {
                 throw new ArgumentException("ArrayMetadata.put_metadata, null or empty key-value!");

sources/TileDB.CSharp/Attribute.cs

@@ -195,7 +195,7 @@ public ulong CellSize()
         /// <param name="data">An array of values that will be used as the fill value.</param>
         private void SetFillValue<T>(T[] data) where T : struct
         {
-            ErrorHandling.ThrowIfManagedType<T>();
+            ErrorHandling.CheckDataType<T>(Type());
             if (data.Length == 0)
             {
                 throw new ArgumentException("Attribute.SetFillValue, data is empty!");

sources/TileDB.CSharp/Dimension.cs

@@ -146,7 +146,7 @@ public DataType Type()
         /// <returns></returns>
         public (T Start, T End) GetDomain<T>() where T : struct
         {
-            ErrorHandling.ThrowIfManagedType<T>();
+            ErrorHandling.CheckDataType<T>(Type());
             void* value_p;
 
             using var ctxHandle = _ctx.Handle.Acquire();
@@ -163,7 +163,7 @@ public DataType Type()
         /// <returns></returns>
         public T TileExtent<T>() where T : struct
         {
-            ErrorHandling.ThrowIfManagedType<T>();
+            ErrorHandling.CheckDataType<T>(Type());
             using var ctxHandle = _ctx.Handle.Acquire();
             using var handle = _handle.Acquire();
             void* value_p;