From da1e7e569fa91efed6d07de0b0c683f54c349ad8 Mon Sep 17 00:00:00 2001
From: Kohsuke Yatoh <kyatoh@google.com>
Date: Wed, 17 Mar 2021 16:56:52 -0700
Subject: [PATCH] Return an empty list instead of null.

TextServicesManager#getEnabledSpellCheckerInfos() was introduced in
  commit 4c7423735e60fdf521678becb1b382c4625aed4a
as #getEnabledSpellCheckersList().
Then, the following commit added SuppressLint("NullableCollections"):
  commit d7f33cd6486e8df59fe71f0b4775ebb525637553

As this API has been introduced recently in Android S timeframe, I think
it's better to fix the API behavior before it's finalized.

Bug: 180625329
Test: m checkapi
Change-Id: I33d3c86a0c19c0082299e383e50d3860b072e79d
---
 core/api/current.txt                                     | 2 +-
 .../android/view/textservice/TextServicesManager.java    | 9 +++++----
 2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/core/api/current.txt b/core/api/current.txt
index 9006212fc4731..9123a2222c032 100644
--- a/core/api/current.txt
+++ b/core/api/current.txt
@@ -52287,7 +52287,7 @@ package android.view.textservice {
 
   public final class TextServicesManager {
     method @Nullable public android.view.textservice.SpellCheckerInfo getCurrentSpellCheckerInfo();
-    method @Nullable public java.util.List<android.view.textservice.SpellCheckerInfo> getEnabledSpellCheckerInfos();
+    method @NonNull public java.util.List<android.view.textservice.SpellCheckerInfo> getEnabledSpellCheckerInfos();
     method public boolean isSpellCheckerEnabled();
     method @Nullable public android.view.textservice.SpellCheckerSession newSpellCheckerSession(@Nullable android.os.Bundle, @Nullable java.util.Locale, @NonNull android.view.textservice.SpellCheckerSession.SpellCheckerSessionListener, boolean);
     method @Nullable public android.view.textservice.SpellCheckerSession newSpellCheckerSession(@Nullable android.os.Bundle, @Nullable java.util.Locale, @NonNull android.view.textservice.SpellCheckerSession.SpellCheckerSessionListener, boolean, int);
diff --git a/core/java/android/view/textservice/TextServicesManager.java b/core/java/android/view/textservice/TextServicesManager.java
index 6fb01a309402d..4f6fa272e1030 100644
--- a/core/java/android/view/textservice/TextServicesManager.java
+++ b/core/java/android/view/textservice/TextServicesManager.java
@@ -37,6 +37,7 @@ import com.android.internal.textservice.ISpellCheckerSessionListener;
 import com.android.internal.textservice.ITextServicesManager;
 
 import java.util.Arrays;
+import java.util.Collections;
 import java.util.List;
 import java.util.Locale;
 
@@ -288,15 +289,15 @@ public final class TextServicesManager {
     }
 
     /**
-     * Retrieve the list of currently enabled spell checkers, or null if there is none.
+     * Retrieve the list of currently enabled spell checkers.
      *
      * @return The list of currently enabled spell checkers.
      */
-    @Nullable
-    @SuppressLint("NullableCollection")
+    @NonNull
     public List<SpellCheckerInfo> getEnabledSpellCheckerInfos() {
         final SpellCheckerInfo[] enabledSpellCheckers = getEnabledSpellCheckers();
-        return enabledSpellCheckers != null ? Arrays.asList(enabledSpellCheckers) : null;
+        return enabledSpellCheckers != null
+                ? Arrays.asList(enabledSpellCheckers) : Collections.emptyList();
     }
 
     /**