When I run AbuseFilter without CheckUser loaded, some test cases of SpecialAbuseLogTest::testTempAccountIPLookup fail:
phpunit ../extensions/AbuseFilter --filter testTempAccountIPLookup 1) MediaWiki\Extension\AbuseFilter\Tests\Integration\Special\SpecialAbuseLogTest::testTempAccountIPLookup with data set "IP with temp account results, user with rights" (Closure Object (...), '1.2.3.4', 2, true) <p>(abusefilter-log-summary)\n </p>\n </div></div></fieldset></form></div><p>(abusefilter-log-noresults)\n </p>' does not contain "(abusefilter-log-noresults)". mediawiki/extensions/AbuseFilter/tests/phpunit/integration/Special/SpecialAbuseLogTest.php:510 2) MediaWiki\Extension\AbuseFilter\Tests\Integration\Special\SpecialAbuseLogTest::testTempAccountIPLookup with data set "IP range with temp account results, user with rights" (Closure Object (...), '1.2.3.0/16', 2, true) <p>(abusefilter-log-summary)\n </p>\n </div></div></fieldset></form></div><p>(abusefilter-log-noresults)\n </p>' does not contain "(abusefilter-log-noresults)". mediawiki/extensions/AbuseFilter/tests/phpunit/integration/Special/SpecialAbuseLogTest.php:510 3) MediaWiki\Extension\AbuseFilter\Tests\Integration\Special\SpecialAbuseLogTest::testTempAccountIPLookup with data set "IP with mix of temp and anonymous results, user with rights" (Closure Object (...), '5.6.7.8', 2, true) Failed asserting that 1 is identical to 2. mediawiki/extensions/AbuseFilter/tests/phpunit/integration/Special/SpecialAbuseLogTest.php:511 4) MediaWiki\Extension\AbuseFilter\Tests\Integration\Special\SpecialAbuseLogTest::testTempAccountIPLookup with data set "IP range with mix of temp and anonymous results, user with rights, should only return temp accounts" (Closure Object (...), '5.6.7.0/16', 1, true) <p>(abusefilter-log-summary)\n </p>\n </div></div></fieldset></form></div><p>(abusefilter-log-noresults)\n </p>' does not contain "(abusefilter-log-noresults)". mediawiki/extensions/AbuseFilter/tests/phpunit/integration/Special/SpecialAbuseLogTest.php:510