GenericTest - function_exists failed to proceed expected assertion with Polyfills

[llaville]

While, I've just fixed all tests running with PHP 8.0.0RC1 (see issue #48), I realized that running unit tests on other platforms PHP 7.x gave unpected results.

i.e:

devilbox@php-7.2.34 in /shared/backups/bartlett/php-compatinfo-db $ /shared/backups/php/phpunit-8.5.phar --stop-on-failure
PHPUnit 8.5.8 by Sebastian Bergmann and contributors.

..............................................SS...........    59 / 12586 (  0%)
...........................................................   118 / 12586 (  0%)
...........................................................   177 / 12586 (  1%)
...........................................................   236 / 12586 (  1%)
...........................................................   295 / 12586 (  2%)
.................SS........................................   354 / 12586 (  2%)
...............................................SSSSSSSSSSSS   413 / 12586 (  3%)
S......................SSSSSSSS....................SSSSSSSS   472 / 12586 (  3%)
.........................................................SS   531 / 12586 (  4%)
SSS........................................................   590 / 12586 (  4%)
...........................................................   649 / 12586 (  5%)
...........................................................   708 / 12586 (  5%)
...........................................................   767 / 12586 (  6%)
F

Time: 13.35 seconds, Memory: 140.00 MB

There was 1 failure:

1) Bartlett\Tests\CompatInfoDb\Reference\Extension\CoreExtensionTest::testGetFunctionsFromReference with data set #38 ('get_resource_id', array('Core', '8.0.0alpha1', '', '8.0.0alpha1', '', '', '', array(), ''), 3)
Function 'get_resource_id', found in Reference (8.0.0alpha1,), exists.
Failed asserting that true is false.

/shared/backups/bartlett/php-compatinfo-db/tests/Reference/GenericTest.php:549
/shared/backups/bartlett/php-compatinfo-db/tests/Reference/GenericTest.php:478
/shared/backups/bartlett/php-compatinfo-db/tests/Reference/GenericTest.php:853

FAILURES!
Tests: 768, Assertions: 721, Failures: 1, Skipped: 38.

Reason is not a regression but usage of polyfills.

When Symfony Components are installed, there are also Symonfy/Polyfill

devilbox@php-7.2.34 in /shared/backups/bartlett/php-compatinfo-db $ composer why symfony/polyfill-php80
symfony/config                v5.1.7  requires  symfony/polyfill-php80 (^1.15)
symfony/console               v5.1.7  requires  symfony/polyfill-php80 (^1.15)
symfony/dependency-injection  v5.1.7  requires  symfony/polyfill-php80 (^1.15)
symfony/string                v5.1.7  requires  symfony/polyfill-php80 (~1.15)

To resume the situation, use function_exists is a trap !!!

We will replace it by either :

• https://www.php.net/manual/en/reflectionfunctionabstract.isinternal.php
• https://www.php.net/manual/en/reflectionfunctionabstract.isuserdefined.php

That will allow us to detect if function really exists or if it's a polyfill.

[llaville]

devilbox@php-7.2.34 in /shared/backups/bartlett/php-compatinfo-db $ /shared/backups/php/phpunit-8.5.phar tests/Reference/Extension/CoreExtensionTest.php
PHPUnit 8.5.8 by Sebastian Bergmann and contributors.

...............................................................  63 / 442 ( 14%)
............................................................... 126 / 442 ( 28%)
............................................................... 189 / 442 ( 42%)
............................................................... 252 / 442 ( 57%)
............................................................... 315 / 442 ( 71%)
............................................................... 378 / 442 ( 85%)
...............................................SS.............. 441 / 442 ( 99%)
.                                                               442 / 442 (100%)

Time: 2.25 seconds, Memory: 22.00 MB

OK, but incomplete, skipped, or risky tests!