The failures are caused by the changes in PHP according to https://wiki.php.net/rfc/notice-for-non-valid-array-container.

When the connection is lost or is closed, subsequent transaction will no longer be nested because they started in a brand new session. Our internal representation of the nesting shold take this into account

Internally, ArrayStatement expects every row to be represented as an array regardless of the fetch mode, however FetchMode::COLUMN produces one value per row.

See https://travis-ci.org/doctrine/dbal/jobs/495144274 for the PPA issue.

See https://travis-ci.org/doctrine/dbal/jobs/488051004 for the dependency issue.

PowerShell doesn't automatically handle exit codes of the invoked commands automatically, and $ErrorActionPreference = "Stop" doesn't seem working. Additionally, the ocular command is moved out of the "test_script" section to "after_test" since it's not part of the actual test.

Link to Slack instead of Gitter