Tests: add new RootPackageHandlingTest

This new test class tests that the plugin correctly registers standards found in the root package if it is an external standard.

Notes:
* This test is about Composer and the plugin, so does not need to be tested against multiple PHPCS versions.

This test class covers the following bugs previously reported:
* Dealerdirect/phpcodesniffer-composer-installer issue 19
* Dealerdirect/phpcodesniffer-composer-installer PR 21
* Dealerdirect/phpcodesniffer-composer-installer issue 20
* Dealerdirect/phpcodesniffer-composer-installer PR 25
* Dealerdirect/phpcodesniffer-composer-installer issue 32

tests/IntegrationTest/RootPackageHandlingTest.php

@@ -0,0 +1,145 @@
+<?php
+
+/**
+ * This file is part of the Dealerdirect PHP_CodeSniffer Standards
+ * Composer Installer Plugin package.
+ *
+ * @copyright 2022 PHPCodeSniffer Composer Installer Contributors
+ * @license MIT
+ */
+
+namespace Dealerdirect\Composer\Plugin\Installers\PHPCodeSniffer\Tests\IntegrationTest;
+
+use Dealerdirect\Composer\Plugin\Installers\PHPCodeSniffer\Plugin;
+use Dealerdirect\Composer\Plugin\Installers\PHPCodeSniffer\Tests\TestCase;
+
+/**
+ * Test that the plugin correctly registers standards found in the root package if it is an external standard,
+ * but doesn't act on root packages which do not have the correct "type".
+ *
+ * This test is about Composer and the plugin, so does not need to be tested against multiple PHPCS versions.
+ *
+ * @link https://github.com/PHPCSStandards/composer-installer/issues/19
+ * @link https://github.com/PHPCSStandards/composer-installer/pull/21
+ * @link https://github.com/PHPCSStandards/composer-installer/issues/20
+ * @link https://github.com/PHPCSStandards/composer-installer/pull/25
+ * @link https://github.com/PHPCSStandards/composer-installer/issues/32
+ */
+final class RootPackageHandlingTest extends TestCase
+{
+    /**
+     * Set up test environment.
+     */
+    protected function set_up()
+    {
+        $this->createTestEnvironment();
+    }
+
+    /**
+     * Clean up.
+     */
+    protected function tear_down()
+    {
+        $this->removeTestEnvironment();
+    }
+
+    /**
+     * Test that the plugin registers a standard found in the root package.
+     *
+     * @return void
+     */
+    public function testSetInstalledPathsWhenRootPackageIsExternalStandard()
+    {
+        /*
+         * Copy one of the fixtures to the test directory.
+         */
+        $this->recursiveDirectoryCopy(dirname(__DIR__) . '/fixtures/multistandard/', static::$tempLocalPath);
+
+        // Install the dependencies, including the plugin.
+        $command = sprintf('composer install -v --no-ansi --working-dir=%s', escapeshellarg(static::$tempLocalPath));
+        $this->assertExecute(
+            $command,
+            0,    // Expected exit code.
+            Plugin::MESSAGE_RUNNING_INSTALLER, // Expected stdout.
+            null, // No stderr expectation.
+            'Failed to install the plugin.'
+        );
+
+        // Verify that the root package standard is registered correctly.
+        $result = $this->executeCliCommand('"vendor/bin/phpcs" --config-show', static::$tempLocalPath);
+        $this->assertSame(0, $result['exitcode'], 'Exitcode for "phpcs --config-show" did not match 0 (first run)');
+
+        $this->assertSame(
+            1,
+            preg_match('`installed_paths:\s+([^\n\r]+)\s+`', $result['stdout'], $matches),
+            'Could not find the installed paths in the config'
+        );
+
+        // Work around differences in paths being returned between *nix and Windows.
+        $hasExpectedPath = false;
+        if ($matches[1] === '../../../') { // Most common.
+            $hasExpectedPath = true;
+        } else {
+            $needle = str_replace(sys_get_temp_dir(), '', static::$tempLocalPath);
+            if (substr_compare($matches[1], $needle, -\strlen($needle)) === 0) {
+                $hasExpectedPath = true;
+            }
+        }
+
+        $this->assertTrue($hasExpectedPath, $matches[1], 'PHPCS configuration does not contain the root standard');
+    }
+
+    /**
+     * Test that the plugin does not act on root packages which aren't valid PHPCS external standards
+     * for the purposes of this plugin.
+     *
+     * @dataProvider dataInvalidRootPackages
+     *
+     * @param string $srcDir The path to the fixture to use as the root package.
+     *
+     * @return void
+     */
+    public function testDontSetInstalledPathsForInvalidPackages($srcDir)
+    {
+        // Copy the fixture to the test directory.
+        $this->recursiveDirectoryCopy($srcDir, static::$tempLocalPath);
+
+        // Install the dependencies, including the plugin.
+        $command = sprintf('composer install -v --no-ansi --working-dir=%s', escapeshellarg(static::$tempLocalPath));
+        $this->assertExecute(
+            $command,
+            0,    // Expected exit code.
+            Plugin::MESSAGE_RUNNING_INSTALLER, // Expected stdout.
+            null, // No stderr expectation.
+            'Failed to install the plugin.'
+        );
+
+        // Verify that the root package is not registered as a standard.
+        $result = $this->executeCliCommand('"vendor/bin/phpcs" --config-show', static::$tempLocalPath);
+        $this->assertSame(0, $result['exitcode'], 'Exitcode for "phpcs --config-show" did not match 0 (first run)');
+
+        // As the fixture doesn't contain other external standards, the installed_paths config should not exist.
+        $this->assertStringNotContainsString(
+            'installed_paths:',
+            $result['stdout'],
+            'Root package registered as an external standard with PHPCS, while it shouldn\'t be'
+        );
+    }
+
+    /**
+     * Data provider.
+     *
+     * @return array
+     */
+    public function dataInvalidRootPackages()
+    {
+        return array(
+            'Root package without ruleset file' => array(
+                'srcDir' => dirname(__DIR__) . '/fixtures/no-ruleset/',
+            ),
+            'Root package with incorrect type' => array(
+                'srcDir' => dirname(__DIR__) . '/fixtures/incorrect-type/',
+            ),
+        );
+    }
+}