Serialize null in rememberSaveable

cashapp · Oct 6, 2023 · 58c0af7 · 58c0af7
1 parent 5c2c4d1
commit 58c0af7
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Showing 2 changed files with 11 additions and 2 deletions.
diff --git a/redwood-treehouse/src/commonMain/kotlin/app/cash/redwood/treehouse/StateSnapshot.kt b/redwood-treehouse/src/commonMain/kotlin/app/cash/redwood/treehouse/StateSnapshot.kt
@@ -21,6 +21,7 @@ import kotlin.jvm.JvmInline
 import kotlinx.serialization.Serializable
 import kotlinx.serialization.json.JsonArray
 import kotlinx.serialization.json.JsonElement
+import kotlinx.serialization.json.JsonNull
 import kotlinx.serialization.json.JsonObject
 import kotlinx.serialization.json.JsonPrimitive
 import kotlinx.serialization.json.booleanOrNull
@@ -62,13 +63,15 @@ private fun Any?.toJsonElement(): JsonElement {
     is Int -> JsonPrimitive(this)
     is List<*> -> JsonArray(map { it.toJsonElement() })
     is JsonElement -> this
+    null -> JsonNull
     else -> error("unexpected type: $this")
     // TODO: add support to Map<*, *>
   }
 }
 
-private fun JsonElement?.fromJsonElement(): Any {
+private fun JsonElement.fromJsonElement(): Any? {
   return when {
+    this is JsonNull -> null
     this is JsonPrimitive -> {
       if (this.isString) return content
       return booleanOrNull ?: doubleOrNull ?: intOrNull ?: error("unexpected type: $this")

diff --git a/redwood-treehouse/src/commonTest/kotlin/app/cash/redwood/treehouse/StateSnapshotTest.kt b/redwood-treehouse/src/commonTest/kotlin/app/cash/redwood/treehouse/StateSnapshotTest.kt
@@ -22,6 +22,7 @@ import assertk.assertions.containsOnly
 import assertk.assertions.isEqualTo
 import kotlin.test.Test
 import kotlin.test.assertTrue
+import kotlinx.serialization.json.JsonNull
 import kotlinx.serialization.json.JsonPrimitive
 
 class StateSnapshotTest {
@@ -30,7 +31,7 @@ class StateSnapshotTest {
   fun toValueMapWorksAsExpected() {
     val stateSnapshot = stateSnapshot()
     val valuesMap = stateSnapshot.toValuesMap()
-    assertThat(valuesMap.entries.size).isEqualTo(4)
+    assertThat(valuesMap.entries.size).isEqualTo(5)
     assertTrue(valuesMap["key1"]!![0] is MutableState<*>)
     assertThat((valuesMap["key1"]!![0] as MutableState<*>).value).isEqualTo(1.0)
 
@@ -40,6 +41,8 @@ class StateSnapshotTest {
     assertThat((valuesMap["key3"]!![0] as MutableState<*>).value).isEqualTo("str")
 
     assertThat(valuesMap["key4"]).isEqualTo(listOf("str"))
+
+    assertThat(valuesMap["key5"]).isEqualTo(listOf(null))
   }
 
   @Test
@@ -51,6 +54,7 @@ class StateSnapshotTest {
       "key2" to listOf(JsonPrimitive(1)),
       "key3" to listOf(JsonMutableState(JsonPrimitive("str"))),
       "key4" to listOf(JsonPrimitive("str")),
+      "key5" to listOf(JsonNull),
     )
   }
 
@@ -60,6 +64,7 @@ class StateSnapshotTest {
       "key2" to listOf(JsonPrimitive(1)),
       "key3" to listOf(JsonMutableState(JsonPrimitive("str"))),
       "key4" to listOf(JsonPrimitive("str")),
+      "key5" to listOf(JsonNull),
     ),
   )
 
@@ -68,5 +73,6 @@ class StateSnapshotTest {
     "key2" to listOf(1),
     "key3" to listOf(mutableStateOf("str")),
     "key4" to listOf("str"),
+    "key5" to listOf(null),
   )
 }