That looks great! Can you think of a way to test that the connection is actually closed? 🤔

It depends on your meaning of "test".. I can Add a test for the close functionality: yes. It will just check if the PDO connection has been set to null. I cannot test if the PDO driver really closes the connection, PDO doesn't expose anything for this.

Do you want me to add a unit test for the connect + close functionality?

I think what would be ideal is that the PdoConnection class throws a ConnectionClosed exception when the internal $pdo variable is accessed if it's null. Right now, I think if we close the connection and try a query, we will have a cannot call method on null type exception.

Then, we can write a test that first ensure the connection works by issuing a query, then closing the connection, and finally expecting the exception when issuing another query

I think what would be ideal is that the PdoConnection class throws a ConnectionClosed exception when the internal $pdo variable is accessed if it's null. Right now, I think if we close the connection and try a query, we will have a cannot call method on null type exception.

Then, we can write a test that first ensure the connection works by issuing a query, then closing the connection, and finally expecting the exception when issuing another query

Implemented the exception and the test using sqllite.

@brendt I do not know why phpstan fails. It occurred because I rebased my branch on the upstream main branch. The errors are not even the files I changed in this PR, or due to it? Any ideas?