More tests, some cleanup

[spaze]

More and better tests

• Automate end-to-end tests (Automate end-to-end tests #336, Add end-to-end test for spaze/security-txt #339; want to add your repo to end-to-end tests, see below? Let me know!)
• Run PHPStan on tests as well (Run PHPStan on tests as well #331)
• Start using the Dead Code Detector (Start using the Dead Code Detector and remove the dead code #332, Bump the Dead Code Detector to 0.12 #338, The Dead Code Detector as part of the main PHPStan config #333)
• Test rule registration (Test rule registration #335)

Cleanup

• Ignore PHPStan's ClassReflection::isEnum error when analyzing the extension code on PHP 7.4 (Ignore PHPStan's ClassReflection::isEnum error when analyzing the extension code on PHP 7.4 #324)
• Don't add phpstan-ignore-errors.php into the package (Don't add phpstan-ignore-errors.php into the package #328)
• Remove the extra config file leftovers (Remove the extra config file leftovers #334)
• Remove the hasConstant check (Remove the hasConstant check #343)

What's an end-to-end test?

A test to ensure the extension still works where it was working before. The test checks out a configured repository, installs the latest version of the extension, then runs PHPStan.

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This discussion was created from the release More tests, some cleanup.