Serialize null when passed to a ZiplineService function with a nu…

…llable `@Contextual` parameter (#1146)
cashapp · Oct 16, 2023 · 5ef12c0 · 5ef12c0
1 parent 7c8a253
commit 5ef12c0
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Showing 2 changed files with 28 additions and 2 deletions.
diff --git a/zipline/src/commonMain/kotlin/app/cash/zipline/internal/bridge/calls.kt b/zipline/src/commonMain/kotlin/app/cash/zipline/internal/bridge/calls.kt
@@ -21,6 +21,7 @@ import app.cash.zipline.ZiplineFunction
 import app.cash.zipline.ZiplineScoped
 import app.cash.zipline.ZiplineService
 import app.cash.zipline.ziplineServiceSerializer
+import kotlinx.serialization.ExperimentalSerializationApi
 import kotlinx.serialization.KSerializer
 import kotlinx.serialization.builtins.ListSerializer
 import kotlinx.serialization.builtins.serializer
@@ -225,6 +226,7 @@ internal class RealCallSerializer(
   }
 }
 
+@OptIn(ExperimentalSerializationApi::class)
 internal class ArgsListSerializer(
   internal val serializers: List<KSerializer<*>>,
 ) : KSerializer<List<*>> {
@@ -235,7 +237,7 @@ internal class ArgsListSerializer(
     encoder.encodeStructure(descriptor) {
       for (i in serializers.indices) {
         @Suppress("UNCHECKED_CAST") // We don't have a type argument T for each parameter.
-        encodeSerializableElement(descriptor, i, serializers[i] as KSerializer<Any?>, value[i])
+        encodeNullableSerializableElement(descriptor, i, serializers[i] as KSerializer<Any?>, value[i])
       }
     }
   }
@@ -245,7 +247,7 @@ internal class ArgsListSerializer(
       val result = mutableListOf<Any?>()
       for (i in serializers.indices) {
         check(decodeElementIndex(descriptor) == i)
-        result += decodeSerializableElement(descriptor, i, serializers[i])
+        result += decodeNullableSerializableElement(descriptor, i, serializers[i])
       }
       check(decodeElementIndex(descriptor) == DECODE_DONE)
       return@decodeStructure result

diff --git a/zipline/src/hostTest/kotlin/app/cash/zipline/ZiplineServiceTest.kt b/zipline/src/hostTest/kotlin/app/cash/zipline/ZiplineServiceTest.kt
@@ -28,7 +28,9 @@ import kotlinx.coroutines.Dispatchers.Unconfined
 import kotlinx.coroutines.runBlocking
 import kotlinx.serialization.Contextual
 import kotlinx.serialization.Serializable
+import kotlinx.serialization.builtins.serializer
 import kotlinx.serialization.modules.SerializersModule
+import kotlinx.serialization.modules.contextual
 
 internal class ZiplineServiceTest {
   @Test
@@ -134,6 +136,28 @@ internal class ZiplineServiceTest {
     assertEquals(setOf("factory"), endpointA.serviceNames)
   }
 
+  @Test
+  fun contextualNullableParameter() = runBlocking(Unconfined) {
+    val serializersModule = SerializersModule {
+      contextual(String.serializer())
+    }
+    val (endpointA, endpointB) = newEndpointPair(this, serializersModule)
+
+    endpointA.bind<ContextualNullableParameter>("factory", RealContextualNullableParameter())
+    val factoryClient = endpointB.take<ContextualNullableParameter>("factory")
+
+    factoryClient.create("hello")
+    factoryClient.create(null)
+  }
+
+  interface ContextualNullableParameter : ZiplineService {
+    fun create(string: @Contextual String?)
+  }
+
+  class RealContextualNullableParameter : ContextualNullableParameter {
+    override fun create(string: String?) = Unit
+  }
+
   interface EchoServiceFactory : ZiplineService {
     fun create(greeting: String): EchoService
   }