Throw NpgsqlException instead of InvalidOperationException on a broken connection by irrationalmentality · Pull Request #6599 · npgsql/npgsql

…connection

When a connection was broken (e.g. by a keepalive failure), CheckReady/CheckOpen treated the Broken state identically to Closed and threw InvalidOperationException ("Connection is not open"). Connection errors should surface as NpgsqlException so callers can handle them as connection failures and recover.

Split the Broken case from Closed in both checks and throw NpgsqlException with a message pointing to the logs. The original break reason is logged when the connector breaks but is not reachable from the connection (which is detached on break), matching the maintainer guidance on npgsql#5605.

Also remove the stale doc note claiming ConnectorState.Broken is not implemented yet.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>