transfer manager test correction

Author: sraptis-scy

README.md

@@ -354,6 +354,7 @@ transferManager.addListener { event ->
 
 // use scanner library of your choice to scan the QR for device engagement
 // when qr content is available, call startQRDeviceEngagement()
+// if qrText is malformed an IllegalArgumentException is propagated to TransferEvent.Error callback
 val qrText: String =
     "mdoc:owBjMS4wAYIB2BhYS6QBAiABIVggN ... 86vSyDAgGjAPUB9ApQmCMM53MkSc202zKjnzq9LA"
 transferManager.startQRDeviceEngagement(qrText)

verifier-core/src/main/java/eu/europa/ec/eudi/verifier/core/transfer/TransferManagerImpl.kt

@@ -137,7 +137,7 @@ class TransferManagerImpl(
     /**
      * Starts device engagement using a QR code.
      * @param qrCode The QR code string.
-     * @throws IllegalArgumentException if the QR code is invalid.
+     * If the QR code is invalid, the error will be reported via the [TransferEvent.Error] callback.
      */
     override fun startQRDeviceEngagement(qrCode: String) {
         logger?.d(TAG, "QR Engagement Request: $qrCode")

verifier-core/src/test/java/eu/europa/ec/eudi/verifier/core/transfer/TransferManagerImplTest.kt

@@ -140,12 +140,19 @@ class TransferManagerImplTest {
     }
 
     @Test
-    fun `startQRDeviceEngagement with garbage QR code throws`() {
+    fun `startQRDeviceEngagement with garbage QR code triggers error event`() {
+        transferManager.addListener(listener)
         val garbageQr = "hYS6QBAiABIVgg0Gzvq_N_tpQNv"
-        every { verificationHelper.setDeviceEngagementFromQrCode(garbageQr) } throws IllegalArgumentException("Invalid QR")
 
-        assertFailsWith<IllegalArgumentException> {
-            transferManager.startQRDeviceEngagement(garbageQr)
+        val thrown = runCatching { transferManager.startQRDeviceEngagement(garbageQr) }.exceptionOrNull()
+        assertNull(thrown, "startQRDeviceEngagement should not throw for invalid QR; error is async")
+
+        // Simulate what the underlying helper would do
+        val ex = IllegalArgumentException("Invalid QR")
+        capturedVerificationListener.onError(ex)
+
+        verify {
+            listener.onEvent(match { it is TransferEvent.Error && it.error == ex })
         }
     }