Clear CheckoutController state after completion

Author: jaynewstrom-stripe

paymentsheet/src/main/java/com/stripe/android/checkout/CheckoutConfirmationResultHandler.kt

@@ -55,7 +55,7 @@ internal class CheckoutConfirmationResultHandler @Inject constructor(
         onSucceeded: suspend (CheckoutSessionResponse?) -> Unit,
     ) {
         // Synchronous confirmation carries the latest response. Next-action confirmation does not,
-        // so the controller retrieves the completed Checkout Session before delivering the result.
+        // so the controller retrieves the completed Checkout Session before clearing its state.
         onSucceeded(result.metadata[CheckoutSessionResponseKey])
         resultCallback.onResult(CheckoutController.Result.Completed())
     }

paymentsheet/src/main/java/com/stripe/android/checkout/CheckoutController.kt

@@ -75,7 +75,8 @@ class CheckoutController @Inject internal constructor(
     }
 
     /**
-     * The latest [Session] data, or `null` until [configure] has completed successfully.
+     * The latest [Session] data, or `null` until [configure] completes successfully and after a
+     * payment flow completes.
      */
     val session: StateFlow<Session?>
         get() = stateHolder.session
@@ -303,6 +304,7 @@ class CheckoutController @Inject internal constructor(
     ) {
         runSerialized {
             confirmationStateUpdater.update(checkoutSessionResponse)
+            stateHolder.state = null
             kotlin.Result.success(Unit)
         }
     }
@@ -1006,7 +1008,8 @@ class CheckoutController @Inject internal constructor(
     @RestrictTo(RestrictTo.Scope.LIBRARY_GROUP)
     sealed interface Result {
         /**
-         * The customer completed the payment flow.
+         * The customer completed the payment flow. The controller's loaded [session] is cleared
+         * before this result is delivered.
          */
         @CheckoutSessionPreview
         @RestrictTo(RestrictTo.Scope.LIBRARY_GROUP)

paymentsheet/src/test/java/com/stripe/android/checkout/CheckoutControllerTest.kt

@@ -1024,7 +1024,7 @@ internal class CheckoutControllerTest {
         }
 
     @Test
-    fun `successful confirmation waits for an in-flight mutation then refreshes state`() =
+    fun `successful confirmation waits for an in-flight mutation then clears state`() =
         runMutationScenario(assertLoadingConsumed = true) {
             val holdMutation = CountDownLatch(1)
             networkRule.checkoutUpdate(
@@ -1056,8 +1056,8 @@ internal class CheckoutControllerTest {
             confirmation.await()
 
             assertThat(isUpdatingTurbine.awaitItem()).isFalse()
-            assertThat(committedState().checkoutSessionResponse).isEqualTo(confirmedResponse)
-            assertThat(controller.session.value).isNotNull()
+            assertThat(committedStateOrNull()).isNull()
+            assertThat(controller.session.value).isNull()
         }
 
     @Test