test: implement tests and ensure correct handling of global hook state

Signed-off-by: Tom Carrio <[email protected]>

Author: tcarrio

hooks/OpenTelemetry/composer.json

@@ -112,7 +112,7 @@
     "dev:test:unit:teardown": "echo 'Tore down for unit tests...'",
     "dev:test:integration": [
       "@dev:test:integration:setup",
-      "echo 'No integration tests to run'",
+      "phpunit --colors=always --testdox --testsuite=integration",
       "@dev:test:integration:teardown"
     ],
     "dev:test:integration:debug": "phpunit --colors=always --testdox -d xdebug.profiler_enable=on",

hooks/OpenTelemetry/src/OpenTelemetryHook.php

@@ -42,7 +42,7 @@ public static function register(): void
             self::$instance = new OpenTelemetryHook();
         }
 
-        if (self::$registeredHook) {
+        if (self::$registeredHook && self::isRegisteredInHooks()) {
             return;
         }
 
@@ -88,4 +88,21 @@ public function supportsFlagValueType(string $flagValueType): bool
     {
         return true;
     }
+
+    /**
+     * Hooks can be cleared by other means so we can't simply memoize whether a registration has occurred
+     *
+     * However if no registration has yet happened then we can absolutely determine that the hook will
+     * not be registered yet.
+     */
+    private static function isRegisteredInHooks(): bool
+    {
+        foreach (OpenFeatureAPI::getInstance()->getHooks() as $hook) {
+            if ($hook instanceof OpenTelemetryHook) {
+                return true;
+            }
+        }
+
+        return false;
+    }
 }

hooks/OpenTelemetry/src/_autoload.php

@@ -1,4 +1,6 @@
 <?php
 
+declare(strict_types=1);
+
 // automatically registers the OTel hook for OpenFeature
-OpenFeature\Hooks\OpenTelemetry\OpenTelemetryHook::register();
+OpenFeature\Hooks\OpenTelemetry\OpenTelemetryHook::register();

hooks/OpenTelemetry/tests/integration/OpenTelemetryHookTest.php

@@ -11,10 +11,26 @@
 
 class OpenTelemetryHookTest extends TestCase
 {
+    public function testIsRegisteredAutomatically(): void
+    {
+        // Given
+        $api = OpenFeatureAPI::getInstance();
+        $api->clearHooks();
+
+        // When
+        // simulates the composer autoload
+        require_once __DIR__ . '/../../src/_autoload.php';
+
+        // Then
+        $this->assertNotEmpty($api->getHooks());
+        $this->assertInstanceOf(Hook::class, $api->getHooks()[0]);
+    }
+
     public function testCanBeRegistered(): void
     {
         // Given
         $api = OpenFeatureAPI::getInstance();
+        $api->clearHooks();
 
         // When
         OpenTelemetryHook::register();