Issue #3134606 by greg.1.anderson, longwave, catch, Kristen Pol, jungle,...

    $scaffold_files->filterFiles($unchanged);

    // Process the list of scaffolded files.

    $scaffold_results = $scaffold_files->process($this->io, $scaffold_options);

    $scaffold_results = $scaffold_files->processScaffoldFiles($this->io, $scaffold_options);

    // Generate an autoload file in the document root that includes the

    // autoload.php file in the vendor directory, wherever that is. Drupal

   * @return \Drupal\Composer\Plugin\Scaffold\Operations\ScaffoldResult[]

   *   The results array.

   */

  public function process(IOInterface $io, ScaffoldOptions $scaffold_options) {

  public function processScaffoldFiles(IOInterface $io, ScaffoldOptions $scaffold_options) {

    $results = [];

    foreach ($this as $project_name => $scaffold_files) {

      $io->write("Scaffolding files for <comment>{$project_name}</comment>:");

    return $results;

  }

  /**

   * Processes the iterator created by ScaffoldFileCollection::create().

   *

   * @param \Drupal\Composer\Plugin\Scaffold\Operations\ScaffoldFileCollection $collection

   *   The iterator to process.

   * @param \Composer\IO\IOInterface $io

   *   The Composer IO object.

   * @param \Drupal\Composer\Plugin\Scaffold\ScaffoldOptions $scaffold_options

   *   The scaffold options.

   *

   * @return \Drupal\Composer\Plugin\Scaffold\Operations\ScaffoldResult[]

   *   The results array.

   *

   * @deprecated. Called when upgrading from the Core Composer Scaffold plugin

   *   version 8.8.x due to a bug in the plugin and handler classes. Do not use

   *   in 8.9.x or 9.x, and remove in Drupal 10.x.

   */

  public static function process(ScaffoldFileCollection $collection, IOInterface $io, ScaffoldOptions $scaffold_options) {

    $results = [];

    foreach ($collection as $project_name => $scaffold_files) {

      $io->write("Scaffolding files for <comment>{$project_name}</comment>:");

      foreach ($scaffold_files as $scaffold_file) {

        $results[$scaffold_file->destination()->relativePath()] = $scaffold_file->process($io, $scaffold_options);

      }

    }

    return $results;

  }

  /**

   * Returns the list of files that have not changed since they were scaffolded.

   *

namespace Drupal\Tests\Composer\Plugin\Scaffold\Functional;

use Composer\Util\Filesystem;

use Drupal\Tests\Composer\Plugin\Scaffold\AssertUtilsTrait;

use Drupal\Tests\Composer\Plugin\Scaffold\ExecTrait;

use Drupal\Tests\Composer\Plugin\Scaffold\Fixtures;

use Drupal\Tests\PhpunitCompatibilityTrait;

use PHPUnit\Framework\TestCase;

/**

  use AssertUtilsTrait;

  use ExecTrait;

  use PhpunitCompatibilityTrait;

  /**

   * The Fixtures object.

    // Packagist is disabled in the fixture; we bring it back by removing the

    // line that disables it.

    $this->mustExec("composer config --unset repositories.packagist.org", $sut);

    $stdout = $this->mustExec("composer require drupal/core-composer-scaffold:8.8.0 --no-plugins 2>&1", $sut);

    $stdout = $this->mustExec("composer require --no-ansi drupal/core-composer-scaffold:8.8.0 --no-plugins 2>&1", $sut);

    $this->assertContains("  - Installing drupal/core-composer-scaffold (8.8.0):", $stdout);

    // We can't force the path repo to re-install over the stable version

    // without removing it, and removing it masks the bugs we are testing for.

    // We will therefore make a git repo so that we can tag an explicit version

    // to require.

    $testVersion = '99.99.99';

    $scaffoldPluginTmpRepo = $this->createTmpRepo($this->fixtures->projectRoot(), $this->fixturesDir, $testVersion);

    // Disable packagist.org and upgrade back to the Scaffold plugin under test.

    // This puts the `"packagist.org": false` config line back in composer.json

    // so that Packagist will no longer be used.

    $this->mustExec("composer remove drupal/core-composer-scaffold --no-plugins", $sut);

    $this->mustExec("composer config repositories.packagist.org false", $sut);

    $stdout = $this->mustExec("composer require drupal/core-composer-scaffold:* 2>&1", $sut);

    $this->assertRegExp("#Installing drupal/core-composer-scaffold.*Symlinking from#", $stdout);

    $this->mustExec("composer config repositories.composer-scaffold vcs 'file:///$scaffoldPluginTmpRepo'", $sut);

    // Using 'mustExec' was giving a strange binary string here.

    $output = $this->mustExec("composer require --no-ansi drupal/core-composer-scaffold:$testVersion 2>&1", $sut);

    $this->assertStringContainsString("Installing drupal/core-composer-scaffold ($testVersion)", $output);

    // Remove a scaffold file and run the scaffold command again to prove that

    // scaffolding is still working.

    unlink("$sut/index.php");

    $this->assertFileExists("$sut/index.php");

  }

  /**

   * Copy the provided source directory and create a temporary git repository.

   *

   * @param string $source

   *   Path to directory to copy.

   * @param string $destParent

   *   Path to location to create git repository.

   * @param string $version

   *   Version to tag the repository with.

   * @return string

   *   Path to temporary git repository.

   */

  protected function createTmpRepo($source, $destParent, $version) {

    $target = $destParent . '/' . basename($source);

    $filesystem = new Filesystem();

    $filesystem->copy($source, $target);

    $this->mustExec("git init", $target);

    $this->mustExec('git config user.email "scaffoldtest@example.com"', $target);

    $this->mustExec('git config user.name "Scaffold Test"', $target);

    $this->mustExec("git add .", $target);

    $this->mustExec("git commit -m 'Initial commit'", $target);

    $this->mustExec("git tag $version", $target);

    return $target;

  }

}