fix #1277 - make sure that the command is disposed at the correct time when...

fix #1277 - make sure that the command is disposed at the correct time when using ExecuteReaderAsync; this means pushing it into WrappedReader, which was in turn overdue some love; as part of that, add netcoreapp2.1 target so we can expose the best reader possible

Dapper.StrongName/Dapper.StrongName.csproj

@@ -5,7 +5,7 @@
     <Title>Dapper (Strong Named)</Title>
     <Description>A high performance Micro-ORM supporting SQL Server, MySQL, Sqlite, SqlCE, Firebird etc..</Description>
     <Authors>Sam Saffron;Marc Gravell;Nick Craver</Authors>
-    <TargetFrameworks>net451;netstandard1.3;netstandard2.0</TargetFrameworks>
+    <TargetFrameworks>net451;netstandard1.3;netstandard2.0;netcoreapp2.1</TargetFrameworks>
     <SignAssembly>true</SignAssembly>
     <PublicSign Condition=" '$(OS)' != 'Windows_NT' ">true</PublicSign>
   </PropertyGroup>
@@ -24,6 +24,10 @@
     <PackageReference Include="System.Reflection.TypeExtensions" Version="4.4.0" />
 
     <!-- it would be nice to use System.Data.Common here, but we need SqlClient for SqlDbType in 1.3, and legacy SqlDataRecord API-->
+    <!--<PackageReference Include="System.Data.Common" Version="4.3.0" />-->
+    <PackageReference Include="System.Data.SqlClient" Version="4.6.0" />
+  </ItemGroup>
+  <ItemGroup Condition="'$(TargetFramework)' == 'netcoreapp2.1'">
     <PackageReference Include="System.Data.SqlClient" Version="4.6.0" />
   </ItemGroup>
   <ItemGroup Condition=" '$(TargetFramework)' == 'netstandard1.3' ">

Dapper/Dapper.csproj

@@ -5,7 +5,7 @@
     <Title>Dapper</Title>
     <Description>A high performance Micro-ORM supporting SQL Server, MySQL, Sqlite, SqlCE, Firebird etc..</Description>
     <Authors>Sam Saffron;Marc Gravell;Nick Craver</Authors>
-    <TargetFrameworks>net451;netstandard1.3;netstandard2.0</TargetFrameworks>
+    <TargetFrameworks>net451;netstandard1.3;netstandard2.0;netcoreapp2.1</TargetFrameworks>
   </PropertyGroup>
   <ItemGroup Condition="'$(TargetFramework)' == 'net451'">
     <Reference Include="System" />
@@ -19,6 +19,10 @@
     <PackageReference Include="System.Reflection.TypeExtensions" Version="4.4.0" />
 
     <!-- it would be nice to use System.Data.Common here, but we need SqlClient for SqlDbType in 1.3, and legacy SqlDataRecord API-->
+    <!--<PackageReference Include="System.Data.Common" Version="4.3.0" />-->
+    <PackageReference Include="System.Data.SqlClient" Version="4.6.0" />
+  </ItemGroup>
+  <ItemGroup Condition="'$(TargetFramework)' == 'netcoreapp2.1'">
     <PackageReference Include="System.Data.SqlClient" Version="4.6.0" />
   </ItemGroup>
   <ItemGroup Condition=" '$(TargetFramework)' == 'netstandard1.3' ">

Dapper/SqlDataRecordListTVPParameter.cs

@@ -84,7 +84,11 @@ static class StructuredHelper
             {
                 il.Emit(OpCodes.Ldarg_0);
                 il.Emit(OpCodes.Castclass, type);
+#if NETSTANDARD1_3
+                il.Emit(OpCodes.Ldc_I4, (int)30); // hard-code the known enum value
+#else
                 il.Emit(OpCodes.Ldc_I4, (int)SqlDbType.Structured);
+#endif
                 il.EmitCall(OpCodes.Callvirt, dbType.GetSetMethod(), null);
             }
 

Dapper/SqlMapper.Async.cs

@@ -1101,7 +1101,7 @@ public static async Task<GridReader> QueryMultipleAsync(this IDbConnection cnn,
         /// </code>
         /// </example>
         public static Task<IDataReader> ExecuteReaderAsync(this IDbConnection cnn, string sql, object param = null, IDbTransaction transaction = null, int? commandTimeout = null, CommandType? commandType = null) =>
-            ExecuteReaderImplAsync(cnn, new CommandDefinition(sql, param, transaction, commandTimeout, commandType, CommandFlags.Buffered), CommandBehavior.Default);
+            ExecuteWrappedReaderImplAsync(cnn, new CommandDefinition(sql, param, transaction, commandTimeout, commandType, CommandFlags.Buffered), CommandBehavior.Default);
 
         /// <summary>
         /// Execute parameterized SQL and return an <see cref="IDataReader"/>.
@@ -1114,7 +1114,7 @@ public static async Task<GridReader> QueryMultipleAsync(this IDbConnection cnn,
         /// or <see cref="T:DataSet"/>.
         /// </remarks>
         public static Task<IDataReader> ExecuteReaderAsync(this IDbConnection cnn, CommandDefinition command) =>
-            ExecuteReaderImplAsync(cnn, command, CommandBehavior.Default);
+            ExecuteWrappedReaderImplAsync(cnn, command, CommandBehavior.Default);
 
         /// <summary>
         /// Execute parameterized SQL and return an <see cref="IDataReader"/>.
@@ -1128,26 +1128,27 @@ public static async Task<GridReader> QueryMultipleAsync(this IDbConnection cnn,
         /// or <see cref="T:DataSet"/>.
         /// </remarks>
         public static Task<IDataReader> ExecuteReaderAsync(this IDbConnection cnn, CommandDefinition command, CommandBehavior commandBehavior) =>
-            ExecuteReaderImplAsync(cnn, command, commandBehavior);
+            ExecuteWrappedReaderImplAsync(cnn, command, commandBehavior);
 
-        private static async Task<IDataReader> ExecuteReaderImplAsync(IDbConnection cnn, CommandDefinition command, CommandBehavior commandBehavior)
+        private static async Task<IDataReader> ExecuteWrappedReaderImplAsync(IDbConnection cnn, CommandDefinition command, CommandBehavior commandBehavior)
         {
             Action<IDbCommand, object> paramReader = GetParameterReader(cnn, ref command);
 
             DbCommand cmd = null;
-            bool wasClosed = cnn.State == ConnectionState.Closed;
+            bool wasClosed = cnn.State == ConnectionState.Closed, disposeCommand = true;
             try
             {
                 cmd = command.TrySetupAsyncCommand(cnn, paramReader);
                 if (wasClosed) await cnn.TryOpenAsync(command.CancellationToken).ConfigureAwait(false);
                 var reader = await ExecuteReaderWithFlagsFallbackAsync(cmd, wasClosed, commandBehavior, command.CancellationToken).ConfigureAwait(false);
                 wasClosed = false;
-                return reader;
+                disposeCommand = false;
+                return WrappedReader.Create(cmd, reader);
             }
             finally
             {
                 if (wasClosed) cnn.Close();
-                cmd?.Dispose();
+                if (cmd != null && disposeCommand) cmd.Dispose();
             }
         }
 

Dapper/SqlMapper.cs

@@ -599,7 +599,7 @@ public static IDataReader ExecuteReader(this IDbConnection cnn, string sql, obje
         {
             var command = new CommandDefinition(sql, param, transaction, commandTimeout, commandType, CommandFlags.Buffered);
             var reader = ExecuteReaderImpl(cnn, ref command, CommandBehavior.Default, out IDbCommand dbcmd);
-            return new WrappedReader(dbcmd, reader);
+            return WrappedReader.Create(dbcmd, reader);
         }
 
         /// <summary>
@@ -615,7 +615,7 @@ public static IDataReader ExecuteReader(this IDbConnection cnn, string sql, obje
         public static IDataReader ExecuteReader(this IDbConnection cnn, CommandDefinition command)
         {
             var reader = ExecuteReaderImpl(cnn, ref command, CommandBehavior.Default, out IDbCommand dbcmd);
-            return new WrappedReader(dbcmd, reader);
+            return WrappedReader.Create(dbcmd, reader);
         }
 
         /// <summary>
@@ -632,7 +632,7 @@ public static IDataReader ExecuteReader(this IDbConnection cnn, CommandDefinitio
         public static IDataReader ExecuteReader(this IDbConnection cnn, CommandDefinition command, CommandBehavior commandBehavior)
         {
             var reader = ExecuteReaderImpl(cnn, ref command, commandBehavior, out IDbCommand dbcmd);
-            return new WrappedReader(dbcmd, reader);
+            return WrappedReader.Create(dbcmd, reader);
         }
 
         /// <summary>
@@ -3696,6 +3696,7 @@ public static void SetTypeName(this DataTable table, string typeName)
         public static ICustomQueryParameter AsTableValuedParameter<T>(this IEnumerable<T> list, string typeName = null) where T : IDataRecord =>
             new SqlDataRecordListTVPParameter<T>(list, typeName);
 
+        /* 
         /// <summary>
         /// Used to pass a IEnumerable&lt;SqlDataRecord&gt; as a TableValuedParameter.
         /// </summary>
@@ -3704,6 +3705,7 @@ public static void SetTypeName(this DataTable table, string typeName)
         public static ICustomQueryParameter AsTableValuedParameter(this IEnumerable<Microsoft.SqlServer.Server.SqlDataRecord> list, string typeName = null) =>
             new SqlDataRecordListTVPParameter<Microsoft.SqlServer.Server.SqlDataRecord>(list, typeName);
         // ^^^ retained to avoid missing-method-exception; can presumably drop in a "major"
+        */
 
         // one per thread
         [ThreadStatic]