Planet 4 is built on top of Wordpress, so it's important to keep an eye on what's coming in future releases. To avoid any surprises we use a CI environmental variable (
WP_VERSION) to set the Wordpress version for all instances. When a new release comes out, we first check its Changelog for any breaking change before we bump that version variable for Planet 4.
If we need to test a different version (eg. when a new release comes out) we can override that global variable for a specific instance. To do so we just need to add a
WP_VERSION in the environment variables of this instance CirclecI config. Example:
job_environments:common_environment: &common_environmentWP_VERSION: 5.4