Check WordPress and PHP requirements before installing a theme or plugin

[mrsdizzie]

This matches the behavior of WordPress core which will refuse to install a plugin if the local copy of WordPress or PHP don't meet the minimum requirements for the most recent version as listed by the plugin authors.

Unfortunately the api is limited and only provides these requirement details for the most recent version, so it isn't possible to find an older version that might work. As a compromise, this code doesn't check requirements if a user provides a specific --version since we can't know the requirements for anything other than the latest version and assume if somebody specifies a version they know it will work or want to try anyway.

[mrsdizzie]

For reference, this is what it looks like trying to install a plugin that doesn't meet requirements in the WordPress dashboard:

[mrsdizzie]

Interesting, this now reveals issues with existing tests like:

Warning: akismet: This plugin does not work with your version of WordPress. Minimum WordPress requirement is 5.8 

When running the WordPress 3.7 test. Several similar errors in the WordPress 6.2 test as many of the plugins we use for the tests actually require newer versions of WordPress.

If the PR seems OK otherwise I can fix those, either by finding new plugins or just by specifying a specific plugin version for those tests (which bypasses this new check).

[swissspidy]

Should we perhaps add an --ignore-requirements arg? As long as you don't activate the plugin/theme, installing an incompatible version is not a problem.

This will also be relevant for #407 (plugin dependencies).

[mrsdizzie]

Should we perhaps add an --ignore-requirements arg? As long as you don't activate the plugin/theme, installing an incompatible version is not a problem.

This will also be relevant for #407 (plugin dependencies).

Sounds good, I added that arg. The only thing left is what to do about failing tests on WP 3.7 and WP 6.2. They are all for the same reason that the plugins we use for these tests have a higher WP requirement and now wp plugin/theme install fails with an appropriate error.

[swissspidy]

The tests involving wporg_last_updated are really flaky right now, so I'm ignoring those failures for now.

[swissspidy]

Nice work!