Npgsql.NpgsqlException (0x80004005): Exception while writing to stream: Cannot access a disposed object.

[asmaa-ayman]

Hello,

I am getting this error each time I run more than two nunit tests in a test suit. It doesn't show up when each test is run separately.

Npgsql.NpgsqlException (0x80004005): Exception while writing to stream ---> System.ObjectDisposedException: Cannot access a disposed object.
Object name: 'System.Net.Sockets.NetworkStream'.
at System.Net.Sockets.NetworkStream.Write(Byte[] buffer, Int32 offset, Int32 size)
at Npgsql.NpgsqlWriteBuffer.d__26.MoveNext() in C:\projects\npgsql\src\Npgsql\NpgsqlWriteBuffer.cs:line 125
at Npgsql.NpgsqlWriteBuffer.d__26.MoveNext() in C:\projects\npgsql\src\Npgsql\NpgsqlWriteBuffer.cs:line 134
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd(Task task)
at Npgsql.NpgsqlCommand.d__84.MoveNext() in C:\projects\npgsql\src\Npgsql\NpgsqlCommand.cs:line 875
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Npgsql.NpgsqlCommand.d__100.MoveNext() in C:\projects\npgsql\src\Npgsql\NpgsqlCommand.cs:line 1233
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Npgsql.NpgsqlCommand.ExecuteDbDataReader(CommandBehavior behavior) in C:\projects\npgsql\src\Npgsql\NpgsqlCommand.cs:line 1132
at Npgsql.NpgsqlCommand.ExecuteReader() in C:\projects\npgsql\src\Npgsql\NpgsqlCommand.cs:line 1102

I am using Npgsql version: 4.0.0 and .NET Framework 4.5.2

[roji]

You're going to have to post some code to show what you're doing. But the problem is probably that you're sharing connections between tests that are running concurrently, which isn't allowed. Make sure each connection is used only within each test's method (don't declare the connection on the class).

[asmaa-ayman]

You are right. I was declaring the connection on class level. Thank you so much.