class DrupalComponentTest

class DrupalComponentTest extends TestCase {
    
    /**
     * Tests that classes in Component do not use any Core class.
     */
    public function testNoCoreInComponent() {
        $component_path = dirname(substr(__DIR__, 0, -strlen(__NAMESPACE__))) . '/lib/Drupal/Component';
        foreach ($this->findPhpClasses($component_path) as $class) {
            $this->assertNoCoreUsage($class);
        }
    }
    
    /**
     * Tests that classes in Component Tests do not use any Core class.
     */
    public function testNoCoreInComponentTests() {
        $component_path = dirname(substr(__DIR__, 0, -strlen(__NAMESPACE__))) . '/tests/Drupal/Tests/Component';
        foreach ($this->findPhpClasses($component_path) as $class) {
            $this->assertNoCoreUsage($class);
        }
    }
    
    /**
     * Tests LICENSE.txt is present and has the correct content.
     *
     * @param $component_path
     *   The path to the component.
     *
     * @dataProvider \Drupal\Tests\Component\DrupalComponentTest::getComponents
     */
    public function testComponentLicense($component_path) {
        $this->assertFileExists($component_path . DIRECTORY_SEPARATOR . 'LICENSE.txt');
        $this->assertSame('e84dac1d9fbb5a4a69e38654ce644cea769aa76b', hash_file('sha1', $component_path . DIRECTORY_SEPARATOR . 'LICENSE.txt'));
    }
    
    /**
     * Data provider.
     *
     * @return array
     */
    public function getComponents() {
        $root_component_path = dirname(substr(__DIR__, 0, -strlen(__NAMESPACE__))) . '/lib/Drupal/Component';
        $component_paths = [];
        foreach (new \DirectoryIterator($root_component_path) as $file) {
            if ($file->isDir() && !$file->isDot()) {
                $component_paths[$file->getBasename()] = [
                    $file->getPathname(),
                ];
            }
        }
        return $component_paths;
    }
    
    /**
     * Searches a directory recursively for PHP classes.
     *
     * @param string $dir
     *   The full path to the directory that should be checked.
     *
     * @return array
     *   An array of class paths.
     */
    protected function findPhpClasses($dir) {
        $classes = [];
        foreach (new \DirectoryIterator($dir) as $file) {
            if ($file->isDir() && !$file->isDot()) {
                $classes = array_merge($classes, $this->findPhpClasses($file->getPathname()));
            }
            elseif ($file->getExtension() == 'php') {
                $classes[] = $file->getPathname();
            }
        }
        return $classes;
    }
    
    /**
     * Asserts that the given class is not using any class from Core namespace.
     *
     * @param string $class_path
     *   The full path to the class that should be checked.
     *
     * @internal
     */
    protected function assertNoCoreUsage(string $class_path) : void {
        $contents = file_get_contents($class_path);
        preg_match_all('/^.*Drupal\\\\Core.*$/m', $contents, $matches);
        $matches = array_filter($matches[0], function ($line) {
            // Filter references that don't really matter.
            return preg_match('/@see|E_USER_DEPRECATED|expectDeprecation/', $line) === 0;
        });
        $this->assertEmpty($matches, "Checking for illegal reference to 'Drupal\\Core' namespace in {$class_path}");
    }
    
    /**
     * Data provider for testAssertNoCoreUsage().
     *
     * @return array
     *   Data for testAssertNoCoreUsage() in the form:
     *   - TRUE if the test passes, FALSE otherwise.
     *   - File data as a string. This will be used as a virtual file.
     */
    public function providerAssertNoCoreUsage() {
        return [
            [
                TRUE,
                '@see \\Drupal\\Core\\Something',
            ],
            [
                FALSE,
                '\\Drupal\\Core\\Something',
            ],
            [
                FALSE,
                "@see \\Drupal\\Core\\Something\n" . '\\Drupal\\Core\\Something',
            ],
            [
                FALSE,
                "\\Drupal\\Core\\Something\n" . '@see \\Drupal\\Core\\Something',
            ],
        ];
    }
    
    /**
     * @covers \Drupal\Tests\Component\DrupalComponentTest::assertNoCoreUsage
     * @dataProvider providerAssertNoCoreUsage
     */
    public function testAssertNoCoreUsage($expected_pass, $file_data) {
        // Set up a virtual file to read.
        $vfs_root = vfsStream::setup('root');
        vfsStream::newFile('Test.php')->at($vfs_root)
            ->setContent($file_data);
        $file_uri = vfsStream::url('root/Test.php');
        try {
            $pass = TRUE;
            $this->assertNoCoreUsage($file_uri);
        } catch (AssertionFailedError $e) {
            $pass = FALSE;
        }
        $this->assertEquals($expected_pass, $pass, $expected_pass ? 'Test caused a false positive' : 'Test failed to detect Core usage');
    }

}