Add AnyInstance matcher. Fix #160

[BrianHenryIE]

Description of the Change

Adds a new matcher, AnyInstance to allow using expectActionAdded and expectFilterAdded without having a reference to the object that will be added to the hook. e.g.

\WP_Mock::expectFilterAdded( 'the_content', array( new \WP_Mock\Matcher\AnyInstance( Special::class ), 'the_content' ) );

Alternate Designs, Benefits, Possible Drawbacks

Discussed in #160, opened in January 2021, which references six further related issues.

Maybe this should be part of Functions::type( $type ).

Verification Process

• I've been using this in my own projects for about six months now, it works as desired. e.g. tests
• I've written unit tests against the new class itself: AnyInstanceTest

• How did you verify that the change has not introduced any regressions?

The existing tests were failing, so I'm not certain.

Checklist:

• I have read the CONTRIBUTING document.
• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my change.
• All new and existing tests passed.

• There is no phpcs.xml in the project.
• The existing tests were already failing.

Applicable Issues

#160, #8, #80, #93, #127, #143, #12.

Changelog Entry

### Added
- AnyInstance matcher

Included in the PR at: CHANGELOG.md

[BrianHenryIE]

The changes to FuzzyObject need particular attention. It's a change to FuzzyObject::haveCommonAncestor() which changes the behaviour to "is the expected class a subclass of the actual class".

Maybe that should be moved into AnyInstance and not interfere with FuzzyObject.

[coveralls]

Coverage increased (+2.0%) to 12.166% when pulling bc9770d on BrianHenryIE:any-instance into b647631 on 10up:trunk.

[BrianHenryIE]

hey @unfulvio-godaddy , is there anything I can do to help get this merged? I've been using it extensively since before the PR and it's been smooth.

[unfulvio-godaddy]

this looks good, thank you @BrianHenryIE

probably in the future we are going to introduce some PHPCS standards to improve on code consistency, but right now I'd like to have this merged since it addressed the problem outlined in some issues and seems fairly straightforward without breaking changes --- thanks