Collect coverage in subprocesses

Author: BenMorel

.github/workflows/ci.yml

@@ -96,7 +96,7 @@ jobs:
         if: ${{ matrix.php-version != env.HIGHEST_PHP_VERSION }}
 
       - name: Run PHPUnit with coverage
-        run: vendor/bin/phpunit --coverage-clover clover.xml
+        run: vendor/bin/phpunit --coverage-php coverage.php
         env:
           DRIVER: mysql_pdo
           MYSQL_HOST: 127.0.0.1
@@ -106,6 +106,10 @@ jobs:
           PDO_ERRMODE: ${{ matrix.pdo-errmode }}
         if: ${{ matrix.php-version == env.HIGHEST_PHP_VERSION }}
 
+      - name: Merge worker coverage
+        run: php tools/merge-coverage.php coverage.php clover.xml && rm coverage.php
+        if: ${{ matrix.php-version == env.HIGHEST_PHP_VERSION }}
+
       - name: Upload coverage to Codecov
         uses: codecov/codecov-action@v5
         env:
@@ -154,13 +158,16 @@ jobs:
           dependency-versions: ${{ matrix.deps }}
 
       - name: Run PHPUnit with coverage
-        run: vendor/bin/phpunit --coverage-clover clover.xml
+        run: vendor/bin/phpunit --coverage-php coverage.php
         env:
           DRIVER: mysql_doctrine
           MYSQL_HOST: 127.0.0.1
           MYSQL_USER: root
           MYSQL_PASSWORD: password
 
+      - name: Merge worker coverage
+        run: php tools/merge-coverage.php coverage.php clover.xml && rm coverage.php
+
       - name: Upload coverage to Codecov
         uses: codecov/codecov-action@v5
         env:
@@ -201,13 +208,16 @@ jobs:
         uses: ramsey/composer-install@v3
 
       - name: Run PHPUnit with coverage
-        run: vendor/bin/phpunit --coverage-clover clover.xml
+        run: vendor/bin/phpunit --coverage-php coverage.php
         env:
           DRIVER: mariadb_pdo
           MARIADB_HOST: 127.0.0.1
           MARIADB_USER: root
           MARIADB_PASSWORD: password
 
+      - name: Merge worker coverage
+        run: php tools/merge-coverage.php coverage.php clover.xml && rm coverage.php
+
       - name: Upload coverage to Codecov
         uses: codecov/codecov-action@v5
         env:
@@ -248,13 +258,16 @@ jobs:
         uses: ramsey/composer-install@v3
 
       - name: Run PHPUnit with coverage
-        run: vendor/bin/phpunit --coverage-clover clover.xml
+        run: vendor/bin/phpunit --coverage-php coverage.php
         env:
           DRIVER: mariadb_doctrine
           MARIADB_HOST: 127.0.0.1
           MARIADB_USER: root
           MARIADB_PASSWORD: password
 
+      - name: Merge worker coverage
+        run: php tools/merge-coverage.php coverage.php clover.xml && rm coverage.php
+
       - name: Upload coverage to Codecov
         uses: codecov/codecov-action@v5
         env:
@@ -293,13 +306,16 @@ jobs:
         uses: ramsey/composer-install@v3
 
       - name: Run PHPUnit with coverage
-        run: vendor/bin/phpunit --coverage-clover clover.xml
+        run: vendor/bin/phpunit --coverage-php coverage.php
         env:
           DRIVER: postgres_pdo
           POSTGRES_HOST: 127.0.0.1
           POSTGRES_USER: postgres
           POSTGRES_PASSWORD: postgres
 
+      - name: Merge worker coverage
+        run: php tools/merge-coverage.php coverage.php clover.xml && rm coverage.php
+
       - name: Upload coverage to Codecov
         uses: codecov/codecov-action@v5
         env:
@@ -338,13 +354,16 @@ jobs:
         uses: ramsey/composer-install@v3
 
       - name: Run PHPUnit with coverage
-        run: vendor/bin/phpunit --coverage-clover clover.xml
+        run: vendor/bin/phpunit --coverage-php coverage.php
         env:
           DRIVER: postgres_doctrine
           POSTGRES_HOST: 127.0.0.1
           POSTGRES_USER: postgres
           POSTGRES_PASSWORD: postgres
 
+      - name: Merge worker coverage
+        run: php tools/merge-coverage.php coverage.php clover.xml && rm coverage.php
+
       - name: Upload coverage to Codecov
         uses: codecov/codecov-action@v5
         env:

.gitignore

@@ -5,3 +5,4 @@
 /tools/*
 !/tools/ecs/composer.json
 !/tools/ecs/ecs.php
+!/tools/merge-coverage.php

tests/Util/Command/Shutdown.php

@@ -0,0 +1,16 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Brick\Lock\Tests\Util\Command;
+
+use Brick\Lock\Tests\Util\CommandInterface;
+use Brick\Lock\Tests\Util\LockContext;
+
+final class Shutdown implements CommandInterface
+{
+    public function execute(LockContext $context): void
+    {
+        exit(0);
+    }
+}

tests/Util/RemoteWorker.php

@@ -9,8 +9,11 @@
 use PHPUnit\Framework\Assert;
 use Symfony\Component\Process\InputStream;
 use Symfony\Component\Process\Process;
+use Throwable;
 
+use function dirname;
 use function explode;
+use function extension_loaded;
 use function implode;
 use function json_encode;
 use function microtime;
@@ -36,7 +39,18 @@ final class RemoteWorker
 
     public function __construct()
     {
-        $this->process = new Process(['php', 'worker.php'], __DIR__);
+        $command = ['php'];
+
+        if (extension_loaded('pcov')) {
+            // pcov.directory defaults to the process CWD (tests/Util/), which excludes src/.
+            // Set it explicitly so pcov tracks the library source files.
+            $command[] = '-d';
+            $command[] = 'pcov.directory=' . dirname(__DIR__, 2) . '/src';
+        }
+
+        $command[] = 'worker.php';
+
+        $this->process = new Process($command, __DIR__);
         $this->input = new InputStream();
 
         $this->process->setInput($this->input);
@@ -235,6 +249,20 @@ private function parseDuration(string $duration): float
 
     public function __destruct()
     {
+        if (! $this->isKilled && $this->process->isRunning()) {
+            try {
+                $this->sendCommand(new Command\Shutdown());
+
+                // Give it enough time to collect coverage.
+                $deadline = microtime(true) + 1.0;
+                while ($this->process->isRunning() && microtime(true) < $deadline) {
+                    usleep(100_000);
+                }
+            } catch (Throwable) {
+                // Ignore errors.
+            }
+        }
+
         $this->process->stop(0);
     }
 }

tests/Util/worker.php

@@ -14,9 +14,26 @@
 use Brick\Lock\Tests\Util\LockDriverFactoryException;
 
 use function Opis\Closure\unserialize;
+use function pcov\collect;
+use function pcov\start;
+use function pcov\stop;
+
+use const pcov\all;
 
 require __DIR__ . '/../../vendor/autoload.php';
 
+if (extension_loaded('pcov')) {
+    start();
+    register_shutdown_function(function (): void {
+        stop();
+        $coverage = collect(all);
+        file_put_contents(
+            sys_get_temp_dir() . '/brick-lock-worker-coverage-' . getmypid() . '.bin',
+            serialize($coverage),
+        );
+    });
+}
+
 try {
     $lockDriverWithInfo = LockDriverFactory::getDriver();
 } catch (LockDriverFactoryException $e) {

tools/merge-coverage.php

@@ -0,0 +1,47 @@
+<?php
+
+/**
+ * Merges worker subprocess coverage data into the main PHPUnit coverage report.
+ *
+ * Usage: php tools/merge-coverage.php <coverage.php> <clover.xml>
+ *
+ * Worker processes (tests/Util/worker.php) save their pcov coverage to temp files
+ * named brick-lock-worker-coverage-<pid>.bin in sys_get_temp_dir(). This script
+ * loads the serialized CodeCoverage object produced by PHPUnit (--coverage-php),
+ * appends each worker's raw coverage data, then writes the merged clover.xml.
+ */
+
+declare(strict_types=1);
+
+require __DIR__ . '/../vendor/autoload.php';
+
+use SebastianBergmann\CodeCoverage\CodeCoverage;
+use SebastianBergmann\CodeCoverage\Data\RawCodeCoverageData;
+use SebastianBergmann\CodeCoverage\Report\Clover;
+
+$coveragePhpFile = $argv[1] ?? __DIR__ . '/../coverage.php';
+$outputFile      = $argv[2] ?? __DIR__ . '/../clover.xml';
+
+/** @var CodeCoverage $coverage */
+$coverage = require $coveragePhpFile;
+
+$workerFiles = glob(sys_get_temp_dir() . '/brick-lock-worker-coverage-*.bin');
+assert($workerFiles !== false);
+
+foreach ($workerFiles as $file) {
+    $data = file_get_contents($file);
+    assert($data !== false);
+
+    $workerData = unserialize($data);
+
+    if (! is_array($workerData) || $workerData === []) {
+        continue;
+    }
+
+    $rawData = RawCodeCoverageData::fromXdebugWithoutPathCoverage($workerData);
+    $coverage->append($rawData, basename($file, '.bin'));
+
+    unlink($file);
+}
+
+(new Clover())->process($coverage, $outputFile);