Add code coverage and test run via GitHub Action

.github/workflows/tests.yml

@@ -0,0 +1,33 @@
+name: Tests
+
+on:
+  # Run manually on demand.
+  workflow_dispatch:
+  # Run automatically when a pull request is created and on each push to it.
+  # The runtime is only ~ 30s due to parallelization.
+  pull_request:
+
+jobs:
+  test:
+    name: 'Run unit tests'
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        php: [ '7.4', '8.2' ]
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v3
+
+      - name: Setup PHP ${{ matrix.php }}
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: ${{ matrix.php }}
+
+      - name: Install dependencies (using the workflow cache)
+        uses: ramsey/composer-install@v2
+
+      - name: Run tests
+        run: |
+          ./vendor/bin/phpunit --group unit

README.md

@@ -60,4 +60,16 @@ StackOverflow (with special tags) and put it as message into Slack channels.
    ```
    composer install
    SLACK_MESSAGE_STRUCTURE="<message-structure>" SLACK_WEBHOOK_URL="<webhook-url>" STACK_APPS_KEY="<app-key>" ./vendor/bin/phpunit --group end-to-end
-   ```
+   ```
+
+### Code coverage
+
+1. Download
+2. Enable Xdebug
+3. Run
+   ```
+   composer install
+   SLACK_WEBHOOK_URL="<webhook-url>" php -dxdebug.mode=coverage ./vendor/bin/phpunit --coverage-clover <coverage-file>
+   ```
+4. Disable Xdebug.
+5. Analyze the coverage file with your favorite IDE.

composer.json

@@ -1,5 +1,6 @@
 {
     "require": {
+        "php": ">=7.4",
         "ext-json": "*",
         "ext-curl": "*"
     },

phpunit.xml

@@ -4,4 +4,9 @@
             <directory>tests</directory>
         </testsuite>
     </testsuites>
-</phpunit>
+    <coverage>
+        <include>
+            <directory suffix=".php">src</directory>
+        </include>
+    </coverage>
+</phpunit>

tests/AbstractTestCase.php

@@ -9,6 +9,8 @@ abstract class AbstractTestCase extends TestCase
 {
     protected array $usedEnvVars = [];
 
+    protected string $testDirectory = '';
+
     protected function setEnvVar($name, $value): void
     {
         putenv("$name=$value");
@@ -30,33 +32,59 @@ protected function createTestDirectory(): void
         }
     }
 
-    protected function addFileToTestDirectory(string $filename, string $content): void
+    protected function getTestDirectory(): string
     {
-        file_put_contents($this->getPathOfTestDirectoryFile($filename), $content);
-    }
+        if ($this->testDirectory === '') {
+            $inheritingClassFQCN = get_class($this);
+            $inheritingClassName = substr($inheritingClassFQCN, strrpos($inheritingClassFQCN, '\\') + 1);
 
-    protected function getPathOfTestDirectoryFile(string $filename): string
-    {
-        return $this->getTestDirectory() . '/' . $filename;
-    }
+            try {
+                $inheritingClassDirectory = dirname((new \ReflectionClass($inheritingClassFQCN))->getFileName());
+            } catch (\ReflectionException $exception) {
+                $inheritingClassDirectory = __DIR__;
+            }
 
-    protected function getTestDirectory(): string
-    {
-        $inheritingClassFQCN = get_class($this);
-        $inheritingClassName = substr($inheritingClassFQCN, strrpos($inheritingClassFQCN, '\\') + 1);
-        return __DIR__ . '/' . $inheritingClassName;
+            $this->testDirectory = $inheritingClassDirectory.'/'.$inheritingClassName;
+        }
+
+        return $this->testDirectory;
     }
 
     protected function removeTestDirectory(): void
     {
         if (is_dir($this->getTestDirectory())) {
-            $files = glob($this->getTestDirectory() . '/*');
-            foreach ($files as $file) {
-                if (is_file($file)) {
-                    unlink($file);
+            $iterator = new \RecursiveIteratorIterator(
+                new \RecursiveDirectoryIterator($this->getTestDirectory(), \FilesystemIterator::SKIP_DOTS),
+                \RecursiveIteratorIterator::CHILD_FIRST
+            );
+            foreach ($iterator as $path) {
+                if ($path->isDir() && !$path->isLink()) {
+                    rmdir($path->getPathname());
+                } else {
+                    unlink($path->getPathname());
                 }
             }
             rmdir($this->getTestDirectory());
         }
     }
-}
+
+    protected function createDirectoryInTestDirectory(string $path): void
+    {
+        mkdir($this->getPathInTestDirectory($path), 0777, true);
+    }
+
+    protected function createFileInTestDirectory(string $path, string $content): void
+    {
+        file_put_contents($this->getPathInTestDirectory($path), $content);
+    }
+
+    protected function getPathInTestDirectory(string $path): string
+    {
+        return $this->getTestDirectory() . '/' . $path;
+    }
+
+    protected function getPathInTestDirectoryAsUrl(string $path): string
+    {
+        return 'file://' . $this->getPathInTestDirectory($path);
+    }
+}

tests/ConnectorTest.php

@@ -218,7 +218,7 @@ public function testEndToEnd(string $slackMessageStructure, array $expected): vo
             $this->markTestSkipped(sprintf('Restrict end-to-end test to %s Slack message structure.', $filterSlackMessageStructure));
         }
 
-        $lastExecutionFilename = $this->getPathOfTestDirectoryFile('last_execution.txt');
+        $lastExecutionFilename = $this->getPathInTestDirectory('last_execution.txt');
         $this->assertFileDoesNotExist($lastExecutionFilename);
 
         $connector = new Connector();