Unable to install module with minimum PHP version requirement on the UI

Fix failing automated test.

Updated the POC with the PHP version that you have referred to, still getting different results: https://3v4l.org/9AOC0.
Sorry, coffee have not kicked yet. :)

I find strange that 7.1 is getting printed as 7.1000000000000004.*. It seems 7.1 is getting changed in a floating point number....

I can also agree with this part of your sentence, but I'd rather change the wording, use "parsed" instead of "printed" because this is what I could see in xDebug:

Quick hotfix to the problem... Adding php: "7.1" instead of php: 7.1 to a module's info.yml file. So could it be just a documentation related issue?

Just make clear the next steps. Does it mean that the `php: 7.1` should not be parsed as `7.1000000000000004.` and this is what should be fixed?

Well, I have just bumped into this old issue again on a project.

I know that there are plans and open issues to refactor the extension system and the module listing page but this is a serious bug that should have been fixed earlier. This bug requires a smaller fix so it has a higher chance that it could be merged sooner than other huge patches in related issues.

Took the idea from the \Drupal\Tests\system\Functional\Form\ModulesListFormWebTest::testModulesListFormWithInvalidInfoFile() to create the necessary test modules from code when the test is running instead of adding them to the codebase.

Meh, test only patch should not pass and it does not pass in my local. Try to figure out why it passes on the CI.

Ehm, probably found the reason why it passes on the CI: https://bugs.php.net/bug.php?id=75213

The problem only occurs if < 2.0.3 is installed from the YAML Pecl extension.

So the test-only patch passes because YAML PECL extension is either not installed on the CI and Drupal fallbacks to symfony/yaml or at least 2.0.3 is installed. But this issue still exists with older YAML PECL versions and I am not sure how it could be enforced to have >= 2.0.3 installed from this optional PHP extension. Consequently, probably the fix in this patch is the best option if we want to add a general fix to Drupal core.

Works for me, but I would probably also keep the new test case that I added which ensures this problem never happens again in the future.

how it could be enforced to have >= 2.0.3 installed from this optional PHP extension.

What I meant with this is we can not enforce the PHP extension version from composer.json. :)

Lemme check what has failed and why.

index 69a7ed74ea..3773a73897 100644
--- a/core/modules/config/tests/src/Functional/ConfigSingleImportExportTest.php
+++ b/core/modules/config/tests/src/Functional/ConfigSingleImportExportTest.php
@@ -172,7 +172,8 @@ public function testImport() {
       'import' => $import,
     ];
     $this->drupalPostForm('admin/config/development/configuration/single/import', $edit, t('Import'));
-    if (extension_loaded('yaml')) {
+    // @see \Drupal\Component\Serialization\Yaml::getSerializer()
+    if (extension_loaded('yaml') && version_compare(phpversion('yaml'), '2.0.3', '>=')) {
       // If the yaml extension is loaded it will work but not create the PHP
       // object.

Well, I could not find a better than this to fix the failing test. Even if there is a serialization.yaml service, everywhere that static methods are being called from the YAML class ¯\_(ツ)_/¯. Otherwise, I could decorate the service and expose the actual serialization for the test to modify the original condition to something like "if Symfony serializer is being used underneath..., otherwise". (Whey there are services in Drupal core that referring to classes which only has public static methods? Like Settings... o.O)

Fixed the failing test and added my new test case from #15 to fix in #18.

Weird, I'll look into this,hopefully this is not caused by another extension issue on PHP 7.3 😜

Okay, I may need some help to figure out why it is failing on the CI...

PHPUnit 6.5.14 by Sebastian Bergmann and contributors.

Runtime:       PHP 7.3.8 with Xdebug 2.7.2
Configuration: /var/www/html/core/phpunit.xml

Testing Drupal\Tests\system\Functional\Module\DependencyTest
Test 'Drupal\Tests\system\Functional\Module\DependencyTest::testCompatiblePhpVersionDependency' started
Test 'Drupal\Tests\system\Functional\Module\DependencyTest::testCompatiblePhpVersionDependency' ended


Time: 12.1 seconds, Memory: 6.00MB

OK (1 test, 13 assertions)

➜  drupal git:(8.7.x) ✗ docker-compose exec php php -r 'foreach (get_loaded_extensions() as $extension) echo $extension . " " . phpversion($extension) . PHP_EOL;' | grep yaml
yaml 2.0.4

 $ composer show symfony/yaml | grep version
versions : * v3.4.30

(which is the same version as the CI installed as I can see)