FFL-1460 Don't return a nullable Map from getFlagAssignmentsSnapshot

Author: yugisu-flux

features/dd-sdk-android-flags/api/apiSurface

@@ -31,7 +31,7 @@ interface com.datadog.android.flags.StateObservable
   fun removeListener(FlagsStateListener)
 class com.datadog.android.flags._FlagsInternalProxy
   constructor(FlagsClient)
-  fun getFlagAssignmentsSnapshot(): Map<String, com.datadog.android.flags.model.UnparsedFlag>?
+  fun getFlagAssignmentsSnapshot(): Map<String, com.datadog.android.flags.model.UnparsedFlag>
   fun trackFlagSnapshotEvaluation(String, com.datadog.android.flags.model.UnparsedFlag, com.datadog.android.flags.model.EvaluationContext)
 enum com.datadog.android.flags.model.ErrorCode
   - PROVIDER_NOT_READY

features/dd-sdk-android-flags/src/main/kotlin/com/datadog/android/flags/_FlagsInternalProxy.kt

@@ -24,10 +24,10 @@ import com.datadog.android.lint.InternalApi
 @InternalApi
 @Suppress("ClassName", "UndocumentedPublicFunction")
 class _FlagsInternalProxy(private val client: FlagsClient) {
-    fun getFlagAssignmentsSnapshot(): Map<String, UnparsedFlag>? = if (client is DatadogFlagsClient) {
+    fun getFlagAssignmentsSnapshot(): Map<String, UnparsedFlag> = if (client is DatadogFlagsClient) {
         client.getFlagAssignmentsSnapshot()
     } else {
-        null
+        emptyMap()
     }
 
     fun trackFlagSnapshotEvaluation(flagKey: String, flag: UnparsedFlag, context: EvaluationContext) {

features/dd-sdk-android-flags/src/main/kotlin/com/datadog/android/flags/internal/DatadogFlagsClient.kt

@@ -432,9 +432,9 @@ internal class DatadogFlagsClient(
      *
      * Supposed to be used by internal Datadog packages to get flags state snapshot for a given evaluation context.
      *
-     * @return A map of flag key to precomputed flag, or null if no flags are available.
+     * @return A map of flag key to an unparsed flag, or an empty map if no flags are available or the client is not ready.
      */
-    internal fun getFlagAssignmentsSnapshot(): Map<String, UnparsedFlag>? = flagsRepository.getFlagsSnapshot()
+    internal fun getFlagAssignmentsSnapshot(): Map<String, UnparsedFlag> = flagsRepository.getFlagsSnapshot()
 
     /**
      * Tracks the evaluation of a flag from an exact flags state snapshot.

features/dd-sdk-android-flags/src/main/kotlin/com/datadog/android/flags/internal/repository/DefaultFlagsRepository.kt

@@ -82,7 +82,7 @@ internal class DefaultFlagsRepository(
         return null
     }
 
-    override fun getFlagsSnapshot(): Map<String, PrecomputedFlag>? {
+    override fun getFlagsSnapshot(): Map<String, PrecomputedFlag> {
         waitForPersistenceLoad()
         val state = atomicState.get()
         if (state != null) {
@@ -93,7 +93,7 @@ internal class DefaultFlagsRepository(
             InternalLogger.Target.USER,
             { WARN_CONTEXT_NOT_SET }
         )
-        return null
+        return emptyMap()
     }
 
     override fun getEvaluationContext(): EvaluationContext? {

features/dd-sdk-android-flags/src/main/kotlin/com/datadog/android/flags/internal/repository/FlagsRepository.kt

@@ -17,5 +17,5 @@ internal interface FlagsRepository {
     fun setFlagsAndContext(context: EvaluationContext, flags: Map<String, PrecomputedFlag>)
     fun getPrecomputedFlagWithContext(key: String): Pair<PrecomputedFlag, EvaluationContext>?
     fun hasFlags(): Boolean
-    fun getFlagsSnapshot(): Map<String, PrecomputedFlag>?
+    fun getFlagsSnapshot(): Map<String, PrecomputedFlag>
 }