Test that a forked worker does not delete the composed ini

A PHP process spawned during the run reads its configuration from the
composed ini through PHPRC. Once a forked worker deletes it, the spawned
process loads neither the ini nor the scan dir, and misses every extension
loaded from them.

Amp-Thread-ID: https://ampcode.com/threads/T-01a17e3b-9bb8-77b1-a5c1-722d8ade601b

Author: ondrejmirtes

.github/workflows/e2e-tests.yml

@@ -2453,6 +2453,30 @@ jobs:
                 exit 1
               fi
 
+          # a PHP process spawned during the run - by an extension compiling
+          # its own DI container, say - reads the composed ini through PHPRC,
+          # so a forked worker that ends must not delete it; the rule spawns
+          # one in the main process after every worker has ended
+          - operating-system: "ubuntu-latest"
+            coverage: "pcov"
+            extensions: ""
+            script: |
+              php ../../bin/phpstan clear-result-cache -c spawn.neon -a SpawnedProcessRule.php
+              set +e
+              php ../../bin/phpstan analyse -c spawn.neon -a SpawnedProcessRule.php --no-progress --error-format=raw -vvv > out.txt 2>&1
+              CODE=$?
+              set -e
+              cat out.txt
+              if ! grep -qE 'Mechanism: +fork' out.txt; then
+                echo "FAIL: the workers were not forked"
+                exit 1
+              fi
+              if [ "$CODE" != "0" ]; then
+                echo "FAIL: the analysis exited with $CODE"
+                exit 1
+              fi
+              php check.php restarted-for=pcov,opcache pcov-armed=no processes=2+ starts=2
+
           # --debug restarts like any other run - it only makes the analysis
           # serial, --xdebug is what keeps xdebug
           - operating-system: "ubuntu-latest"

e2e/restart-manager/SpawnedProcessRule.php

@@ -0,0 +1,72 @@
+<?php declare(strict_types = 1);
+
+namespace RestartManagerE2E;
+
+use PhpParser\Node;
+use PHPStan\Analyser\Scope;
+use PHPStan\Collectors\Collector;
+use PHPStan\Node\CollectedDataNode;
+use PHPStan\Node\FileNode;
+use PHPStan\Rules\Rule;
+use PHPStan\Rules\RuleErrorBuilder;
+
+/**
+ * Spawns a PHP process the way an extension compiling its own DI container
+ * does. It runs in the main process after every worker has ended, so a worker
+ * that took the composed ini with it leaves the spawned process with neither
+ * the ini nor the scan dir - and without the extensions loaded from them.
+ *
+ * @implements Rule<CollectedDataNode>
+ */
+final class SpawnedProcessRule implements Rule
+{
+
+	public function getNodeType(): string
+	{
+		return CollectedDataNode::class;
+	}
+
+	public function processNode(Node $node, Scope $scope): array
+	{
+		$output = shell_exec(escapeshellarg(PHP_BINARY) . ' -r ' . escapeshellarg('echo json_encode(get_loaded_extensions());'));
+		$spawnedExtensions = json_decode((string) $output, true);
+		if (!is_array($spawnedExtensions)) {
+			return [RuleErrorBuilder::message(sprintf('The spawned PHP process failed: %s', $output))->identifier('restartManager.spawn')->build()];
+		}
+
+		$missing = array_diff(get_loaded_extensions(), $spawnedExtensions);
+		if ($missing === []) {
+			return [];
+		}
+
+		return [
+			RuleErrorBuilder::message(sprintf(
+				'The spawned PHP process is missing extensions %s (PHPRC=%s, %s)',
+				implode(', ', $missing),
+				(string) getenv('PHPRC'),
+				is_file((string) getenv('PHPRC')) ? 'exists' : 'does not exist',
+			))->identifier('restartManager.spawn')->build(),
+		];
+	}
+
+}
+
+/**
+ * CollectedDataNode rules only run when something was collected.
+ *
+ * @implements Collector<FileNode, true>
+ */
+final class FileCollector implements Collector
+{
+
+	public function getNodeType(): string
+	{
+		return FileNode::class;
+	}
+
+	public function processNode(Node $node, Scope $scope): bool
+	{
+		return true;
+	}
+
+}

e2e/restart-manager/spawn.neon

@@ -0,0 +1,11 @@
+includes:
+	- phpstan.neon
+
+rules:
+	- RestartManagerE2E\SpawnedProcessRule
+
+services:
+	-
+		class: RestartManagerE2E\FileCollector
+		tags:
+			- phpstan.collector

tests/PHPStan/Process/Restart/RestartManagerTest.php

@@ -6,9 +6,19 @@
 use PHPUnit\Framework\Attributes\CoversNothing;
 use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\TestCase;
+use function fclose;
+use function function_exists;
 use function getenv;
+use function is_file;
+use function proc_close;
+use function proc_open;
 use function putenv;
 use function sprintf;
+use function stream_get_contents;
+use function sys_get_temp_dir;
+use function tempnam;
+use function unlink;
+use const PHP_BINARY;
 
 #[CoversNothing]
 class RestartManagerTest extends TestCase
@@ -153,4 +163,29 @@ public function testNonRestartingCommandsCollectNoReasons(): void
 		$this->assertSame([], RestartManager::collectReasons(['bin/phpstan', 'diagnose']));
 	}
 
+	public function testAForkedWorkerDoesNotDeleteTheComposedIni(): void
+	{
+		if (!function_exists('pcntl_fork')) {
+			$this->markTestSkipped('Requires pcntl.');
+		}
+
+		$temporaryIni = tempnam(sys_get_temp_dir(), 'phpstan-restart-ini-test-');
+		$this->assertNotFalse($temporaryIni);
+
+		$environment = getenv();
+		$environment['PHPSTAN_RESTART_INI'] = $temporaryIni;
+		$process = proc_open([PHP_BINARY, __DIR__ . '/data/forked-child-ends.php'], [1 => ['pipe', 'w']], $pipes, null, $environment);
+		$this->assertIsResource($process);
+		$output = stream_get_contents($pipes[1]);
+		fclose($pipes[1]);
+		proc_close($process);
+
+		$deletedByOwner = !is_file($temporaryIni);
+		@unlink($temporaryIni);
+
+		// spawned PHP processes read their configuration from it until the run ends
+		$this->assertSame('kept', $output);
+		$this->assertTrue($deletedByOwner);
+	}
+
 }

tests/PHPStan/Process/Restart/data/forked-child-ends.php

@@ -0,0 +1,23 @@
+<?php declare(strict_types = 1);
+
+// The restarted process: it adopts the composed ini named in
+// PHPSTAN_RESTART_INI, forks a worker that ends normally, and reports whether
+// the ini survived the worker.
+
+use PHPStan\Process\Restart\RestartManager;
+
+require __DIR__ . '/../../../../../vendor/autoload.php';
+
+$temporaryIni = (string) getenv('PHPSTAN_RESTART_INI');
+
+// diagnose never restarts, so this only takes ownership of the ini
+RestartManager::run(['bin/phpstan', 'diagnose']);
+
+$pid = pcntl_fork();
+if ($pid === 0) {
+	exit(0);
+}
+
+pcntl_waitpid($pid, $status);
+
+echo is_file($temporaryIni) ? 'kept' : 'deleted';