Migrate PHPSpec tests to PHPUnit (#281)

## Summary
Drop PHPSpec in favor of PHPUnit. Reorganize test structure to follow
Symfony conventions.

### Changes:
- Migrate 9 PHPSpec specs to PHPUnit test classes
- Remove `phpspec/phpspec` dependency
- Upgrade to PHPUnit ^11.5 and
`matthiasnoback/symfony-dependency-injection-test` ^6.0
- Reorganize tests from `src/Bundle/test(s)/` to top-level `tests/` with
PSR-4 namespace `Sylius\Bundle\MailerBundle\Tests\`
- Move test utilities to `tests/Helper/` (renamed from Fixtures - more
accurate for utility classes)
- Remove deprecated SwiftMailer support from test utilities
- Use `testCamelCase` naming convention (PHPUnit standard) instead of
`it_snake_case` (PHPSpec style)
- Fix CI workflow env name bug (`test_no_mailers` →
`test_with_no_mailers`)

### Test structure:
```
tests/
├── Application/     # Test kernel and config (MicroKernelTrait)
├── Cli/             # CLI command tests
├── Helper/          # Test utilities (SentMessage, MessagesProvider, SentMessagesPurger)
├── Functional/      # Functional tests (DI, Compiler passes, Sender)
├── Integration/     # Integration tests (with symfony/translation)
└── Unit/
    ├── Bundle/      # Bundle unit tests (9 migrated from PHPSpec)
    └── Component/   # Component unit tests
```

All 52 tests pass.

Author: TheMilek

.github/workflows/build.yml

@@ -52,19 +52,11 @@ jobs:
                     composer analyse
                     (cd src/Component && composer validate --strict)
 
-            -
-                name: Run component tests
-                run: (cd src/Component && vendor/bin/phpspec run)
-
-            -
-                name: Run PHPSpec tests
-                run: vendor/bin/phpspec run
-
             -
                 name: Test bundle (with all services)
                 run: |
-                    rm -rf src/Bundle/test/var/cache
-                    (cd src/Bundle/test && APP_ENV=test bin/console lint:container)
+                    rm -rf tests/Application/var/cache
+                    (cd tests/Application && APP_ENV=test bin/console lint:container)
                     vendor/bin/phpunit --testsuite "SyliusMailerBundle Test Suite"
 
             -
@@ -76,6 +68,6 @@ jobs:
             -
                 name: Run lint container (with no mailers)
                 run: |
-                    rm -rf src/Bundle/test/var/cache
+                    rm -rf tests/Application/var/cache
                     composer remove symfony/mailer --dev --no-scripts
-                    (cd src/Bundle/test && APP_ENV=test_no_mailers bin/console lint:container)
+                    (cd tests/Application && APP_ENV=test_with_no_mailers bin/console lint:container)

.gitignore

@@ -1,7 +1,10 @@
 /vendor/
 /bin/
+/var/
+/tests/Application/var/
 
 /composer.phar
 /composer.lock
 
 /.phpunit.result.cache
+.phpunit.cache/

composer.json

@@ -37,13 +37,11 @@
         "sylius/mailer": "self.version"
     },
     "require-dev": {
-        "matthiasnoback/symfony-dependency-injection-test": "^5.0",
-        "phpspec/phpspec": "^7.0",
+        "matthiasnoback/symfony-dependency-injection-test": "^6.0",
         "phpstan/phpstan": "1.12.5",
         "phpstan/phpstan-phpunit": "1.4.0",
         "phpstan/phpstan-webmozart-assert": "1.2.11",
-        "phpunit/phpunit": "^10.5",
-        "rector/rector": "^0.13.6",
+        "phpunit/phpunit": "^11.5",
         "sylius-labs/coding-standard": "^4.0",
         "symfony/console": "^6.4 || ^7.4",
         "symfony/dotenv": "^6.4 || ^7.4",
@@ -69,17 +67,12 @@
         "psr-4": {
             "Sylius\\Bundle\\MailerBundle\\": "src/Bundle/",
             "Sylius\\Component\\Mailer\\": "src/Component/"
-        },
-        "exclude-from-classmap": [
-            "src/Bundle/test/"
-        ]
+        }
     },
     "autoload-dev": {
         "psr-4": {
-            "Sylius\\Bundle\\MailerBundle\\spec\\": "src/Bundle/spec/",
-            "Sylius\\Bundle\\MailerBundle\\Tests\\": "src/Bundle/test/",
-            "Sylius\\Component\\Mailer\\spec\\": "src/Component/spec/",
-            "App\\": "src/Bundle/test/src/"
+            "Sylius\\Bundle\\MailerBundle\\Tests\\": "tests/",
+            "App\\": "tests/Application/"
         }
     },
     "scripts": {
@@ -92,7 +85,7 @@
             "vendor/bin/ecs check src --fix"
         ],
         "test": [
-            "vendor/bin/phpspec run --ansi --no-interaction"
+            "vendor/bin/phpunit --colors=always"
         ]
     }
 }

ecs.php

@@ -1,6 +1,5 @@
 <?php
 
-use PhpCsFixer\Fixer\ClassNotation\VisibilityRequiredFixer;
 use PhpCsFixer\Fixer\Comment\HeaderCommentFixer;
 use PhpCsFixer\Fixer\Phpdoc\NoSuperfluousPhpdocTagsFixer;
 use PhpCsFixer\Fixer\Phpdoc\PhpdocTagTypeFixer;
@@ -35,7 +34,6 @@
     $config->skip([
         PhpdocTagTypeFixer::class,
         InlineDocCommentDeclarationSniff::class . '.MissingVariable',
-        VisibilityRequiredFixer::class => ['*Spec.php'],
         NoSuperfluousPhpdocTagsFixer::class => ['src/Component/Sender/SenderInterface.php'],
         '**/var/*',
         '**/vendor/*',

phpspec.yml.dist

@@ -10,11 +10,10 @@ parameters:
     excludePaths:
         - %currentWorkingDirectory%/src/Bundle/DependencyInjection/Configuration.php
         - %currentWorkingDirectory%/src/Bundle/DependencyInjection/SyliusMailerExtension.php
-        - %currentWorkingDirectory%/src/Bundle/spec/*
         - %currentWorkingDirectory%/src/Bundle/test/*
         - %currentWorkingDirectory%/src/Bundle/tests/*
-        - %currentWorkingDirectory%/src/Component/spec/*
         - %currentWorkingDirectory%/src/Component/vendor/*
+        - %currentWorkingDirectory%/tests/*
 
     ignoreErrors:
         - '/Property Sylius\\Component\\Mailer\\Model\\Email\:\:\$id is never written\, only read\./'

phpstan.neon

@@ -1,20 +1,23 @@
 <?xml version="1.0" encoding="UTF-8"?>
 
 <phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xsi:noNamespaceSchemaLocation="http://schema.phpunit.de/9.4/phpunit.xsd"
+         xsi:noNamespaceSchemaLocation="http://schema.phpunit.de/11.5/phpunit.xsd"
          colors="true"
+         bootstrap="tests/Application/config/bootstrap.php"
+         defaultTestSuite="SyliusMailerBundle Test Suite"
 >
     <php>
         <server name="KERNEL_CLASS" value="App\Kernel" />
     </php>
 
     <testsuites>
         <testsuite name="SyliusMailerBundle Test Suite">
-            <directory>./src/Bundle/tests/</directory>
-            <exclude>./src/Bundle/tests/Integration/Cli/</exclude>
+            <directory>./tests/</directory>
+            <exclude>./tests/Integration/</exclude>
+            <exclude>./tests/Application/</exclude>
         </testsuite>
         <testsuite name="SyliusMailerBundle Integration Test Suite">
-            <directory>./src/Bundle/tests/Integration/Cli/</directory>
+            <directory>./tests/Integration/</directory>
         </testsuite>
     </testsuites>
 </phpunit>