test: add comprehensive PHP version detection tests

Add 13 new black-box tests covering all PHP version detection paths:
set/reset, staged versions, auto-detection from composer.json and
slic.json, CLI override, .env.slic.local override, priority ordering,
version normalization, and invalid format rejection.

Move shared helpers (dockerMockEnv, setUpPluginsDir) to BaseTestCase
and add tearDown stack cleanup to prevent orphaned registry entries.

Author: lucatume

tests/Cli/BaseTestCase.php

@@ -3,32 +3,98 @@
 namespace StellarWP\Slic\Test\Cli;
 
 use PHPUnit\Framework\TestCase;
+use StellarWP\Slic\Test\Support\Factories\Directory;
 
 abstract class BaseTestCase extends TestCase {
 	protected ?string $initialDir = null;
 
+	/**
+	 * Stack IDs created during the test, to be cleaned up in tearDown.
+	 *
+	 * @var string[]
+	 */
+	private array $createdStackIds = [];
+
+	private static string $dockerMockBin = '';
+
+	public static function setUpBeforeClass(): void {
+		parent::setUpBeforeClass();
+		self::$dockerMockBin = dirname( __DIR__ ) . '/_support/bin/docker-mock';
+	}
+
 	public function setUp(): void {
 		parent::setUp();
 		$this->initialDir = getcwd();
 	}
 
 	public function tearDown(): void {
-		parent::tearDown();
+		// Restore working directory first so stack stop can resolve paths.
 		chdir( $this->initialDir );
+
+		// Unregister any stacks created during the test.
+		foreach ( $this->createdStackIds as $stackId ) {
+			$this->slicExec(
+				'stack stop ' . escapeshellarg( $stackId ),
+				$this->dockerMockEnv()
+			);
+		}
+
+		parent::tearDown();
 	}
 
 	/**
 	 * Execute a slic command and return the output.
 	 *
-	 * @param string $command The command to execute, escaped if required.
+	 * @param string               $command The command to execute, escaped if required.
+	 * @param array<string,string> $env     Optional environment variables to set for the command.
 	 *
 	 * @return string The command output.
 	 */
-	protected function slicExec( string $command ): string {
-		// Execute the command with NO_COLOR set to avoid color codes in the output.
-		$commandString = 'NO_COLOR=1 php ' . escapeshellarg( dirname( __DIR__, 2 ) . '/slic.php' ) . ' ' . $command;
+	protected function slicExec( string $command, array $env = [] ): string {
+		$env['NO_COLOR'] = '1';
+
+		$envString = '';
+		foreach ( $env as $key => $value ) {
+			$envString .= $key . '=' . escapeshellarg( $value ) . ' ';
+		}
+
+		$commandString = $envString . 'php ' . escapeshellarg( dirname( __DIR__, 2 ) . '/slic.php' ) . ' ' . $command;
 
 		// Redirect stderr to stdout to capture all output.
 		return (string) shell_exec( $commandString . ' 2>&1' );
 	}
+
+	/**
+	 * Returns env vars that mock docker binaries so that no real docker commands are executed.
+	 *
+	 * @return array<string,string>
+	 */
+	protected function dockerMockEnv(): array {
+		return [
+			'SLIC_DOCKER_BIN'         => self::$dockerMockBin,
+			'SLIC_DOCKER_COMPOSE_BIN' => self::$dockerMockBin,
+		];
+	}
+
+	/**
+	 * Creates a temporary plugins directory with a plugin, chdirs into it, and runs `slic here`.
+	 *
+	 * The created stack is automatically unregistered during tearDown.
+	 *
+	 * @param string $pluginName The name of the plugin directory to create.
+	 *
+	 * @return string The absolute path to the plugins directory.
+	 */
+	protected function setUpPluginsDir( string $pluginName = 'test-plugin' ): string {
+		$pluginsDir = Directory::createTemp()
+		                       ->createPlugin( $pluginName )
+		                       ->getAbsolutePath();
+		chdir( $pluginsDir );
+		$this->slicExec( 'here' );
+
+		// Track the stack ID (resolved path) for cleanup.
+		$this->createdStackIds[] = realpath( $pluginsDir );
+
+		return $pluginsDir;
+	}
 }