diff --git a/tests/unit/Converter/Proxy/CacheTest.php b/tests/unit/Converter/Proxy/CacheTest.php
index 4483e9c3..fb2a3484 100644
--- a/tests/unit/Converter/Proxy/CacheTest.php
+++ b/tests/unit/Converter/Proxy/CacheTest.php
@@ -6,6 +6,7 @@
 
 use Smile\GdprDump\Converter\Parameters\ValidationException;
 use Smile\GdprDump\Converter\Proxy\Cache;
+use Smile\GdprDump\Converter\Randomizer\RandomizeText;
 use Smile\GdprDump\Tests\Framework\Mock\Converter\ConverterMock;
 use Smile\GdprDump\Tests\Unit\Converter\TestCase;
 use stdClass;
@@ -13,26 +14,43 @@
 class CacheTest extends TestCase
 {
     /**
-     * Test the converter.
+     * Assert that values are properly cached.
      */
-    public function testConverter(): void
+    public function testValueIsCached(): void
     {
-        $converter1 = $this->createConverter(Cache::class, [
-            'converter' => $this->createConverter(ConverterMock::class, ['prefix' => '1_']),
+        $parameters = [
+            'converter' => $this->createConverter(RandomizeText::class),
             'cache_key' => 'key1',
-        ]);
-        $converter2 = $this->createConverter(Cache::class, [
-            'converter' => $this->createConverter(ConverterMock::class, ['prefix' => '2_']),
-            'cache_key' => 'key2',
-        ]);
+        ];
+
+        $converter = $this->createConverter(Cache::class, $parameters);
+        $value = 'text to randomize';
+        $convertedValue = $converter->convert($value);
+
+        // The converter must always return the same result for a given value
+        $this->assertSame($convertedValue, $converter->convert($value));
+        $this->assertNotSame($convertedValue, $converter->convert('another text to randomize'));
+
+        // Value generated must not be the same when using another cache key
+        $converter->setParameters(array_merge($parameters, ['cache_key' => 'key2']));
+        $this->assertNotSame($convertedValue, $converter->convert($value));
+    }
 
-        $value = 'textToAnonymize';
-        $value1 = $converter1->convert($value);
-        $value2 = $converter1->convert($value);
-        $this->assertSame($value1, $value2);
+    /**
+     * Assert that that the cache storage is shared between converter instances.
+     */
+    public function testCacheIsSharedBetweenInstances(): void
+    {
+        $value = 'text to randomize';
+        $parameters = [
+            'converter' => $this->createConverter(RandomizeText::class),
+            'cache_key' => 'key1',
+        ];
 
-        $value3 = $converter2->convert($value);
-        $this->assertNotSame($value3, $value2);
+        $this->assertSame(
+            $this->createConverter(Cache::class, $parameters)->convert($value),
+            $this->createConverter(Cache::class, $parameters)->convert($value)
+        );
     }
 
     /**