Slightly more robust SessionTest and cleanup (#9376)

* Slightly more robust SessionTest and cleanup

Improvement of #9311

I noticed that my `/tmp` directory got filled up with random `sess_*` files and empty `frss_test_sessions_*` directories after repeatedly running PHPUnit, which means there was no proper cleanup being done in the tests.

See the first commit for changes, since I also moved the test to a more appropriate directory name (alongside `tests/lib/Minz`, `tests/app/Minz` was newly added in #9311).

Before the PR:
* Check output of `ls -lah /tmp/{frss_test_sessions_*,sess_*}; rm -r /tmp/{frss_test_sessions_*,sess_*}` to confirm there are initially no temporary files existing.
* Run `composer run phpunit`.
* Check output of the previous command again to confirm there is a new `sess_*` file and an empty `frss_test_sessions_*` directory.

After the PR:
* Check output of `ls -lah /tmp/{frss_test_sessions_*,sess_*}; rm -r /tmp/{frss_test_sessions_*,sess_*}` to confirm that no temporary files exist initially.
* Run `composer run phpunit`.
* Check output of the previous command again to confirm there are no temporary files, since they are now being cleaned up correctly.

* Move SessionTest from tests/app/Minz to tests/lib/Minz

tests/app/Minz/SessionTest.php

@@ -1,38 +0,0 @@
-<?php
-declare(strict_types=1);
-
-final class SessionTest extends \PHPUnit\Framework\TestCase {
-
-	private string $originalSavePath;
-
-	#[\Override]
-	protected function setUp(): void {
-		$this->originalSavePath = (string)ini_get('session.save_path');
-	}
-
-	#[\Override]
-	protected function tearDown(): void {
-		ini_set('session.save_path', $this->originalSavePath);
-	}
-
-	public function testRegenerateIDOnHealthyStorage(): void {
-		$previous = $_SESSION ?? [];
-
-		Minz_Session::regenerateID('FreshRSS');
-
-		$_SESSION['probe'] = 'ok';
-		self::assertSame('ok', $_SESSION['probe']);
-		$_SESSION = $previous;
-		session_write_close();
-	}
-
-	public function testRegenerateIDOnBrokenStorage(): void {
-		$save_path = sys_get_temp_dir() . '/frss_test_sessions_' . bin2hex(random_bytes(4));
-		self::assertNotFalse(mkdir($save_path, 0700));
-		$broken_path = $save_path . '/missing_subdir';
-		ini_set('session.save_path', $broken_path);
-
-		$this->expectException(RuntimeException::class);
-		Minz_Session::regenerateID('FreshRSS');
-	}
-}

tests/lib/Minz/SessionTest.php

@@ -0,0 +1,47 @@
+<?php
+declare(strict_types=1);
+
+final class SessionTest extends \PHPUnit\Framework\TestCase {
+
+	private string $originalSavePath = '';
+	private string $testSavePath = '';
+
+	#[\Override]
+	protected function setUp(): void {
+		$this->originalSavePath = (string)ini_get('session.save_path');
+	}
+
+	#[\Override]
+	protected function tearDown(): void {
+		if (is_dir($this->testSavePath)) {
+			rmdir($this->testSavePath);
+		}
+
+		ini_set('session.save_path', $this->originalSavePath);
+	}
+
+	public function testRegenerateIDOnHealthyStorage(): void {
+		$save_path = session_save_path() ?: sys_get_temp_dir();
+		Minz_Session::init('FreshRSS', volatile: false);
+		self::assertTrue(file_exists($save_path . '/sess_' . session_id()));
+		$previous_id = session_id();
+		Minz_Session::_param('probe', 'ok');
+		Minz_Session::regenerateID('FreshRSS');
+		self::assertNotSame($previous_id, session_id());
+		self::assertFalse(file_exists($save_path . '/sess_' . $previous_id));
+		self::assertTrue(file_exists($save_path . '/sess_' . session_id()));
+		self::assertSame('ok', Minz_Session::paramString('probe'));
+		session_unset();
+		session_write_close();
+		unlink($save_path . '/sess_' . session_id());
+	}
+
+	public function testRegenerateIDOnBrokenStorage(): void {
+		$this->testSavePath = sys_get_temp_dir() . '/frss_test_sessions_' . bin2hex(random_bytes(4));
+		self::assertNotFalse(mkdir($this->testSavePath, 0700));
+		ini_set('session.save_path', $this->testSavePath . '/missing_subdir');
+
+		$this->expectException(RuntimeException::class);
+		Minz_Session::regenerateID('FreshRSS');
+	}
+}