From 8edcadc04ce04b216cdd1a280217412b7a47b29b Mon Sep 17 00:00:00 2001
From: Seigo Nonaka <nona@google.com>
Date: Thu, 27 Apr 2023 11:27:07 +0900
Subject: [PATCH] Update ALT+DEL/FORWARD_DEL behavior

Old behavior
ALT+DEL: delete entire line
ALT+FORWARD_DEL: delete entire line

New behavior
ALT+DEL: delete characters after the cursor until line end offset.
ALT_FORWARD_DEL: delete characters before the cursor until line start offset.

Bug: 279723106
Test: atest android.text.method.cts.BaseKeyListenerTest
Change-Id: I725a929a224a2087b8809e5862d433ec113d67c0
---
 .../android/text/method/BaseKeyListener.java  | 26 +++++++++++++++----
 1 file changed, 21 insertions(+), 5 deletions(-)

diff --git a/core/java/android/text/method/BaseKeyListener.java b/core/java/android/text/method/BaseKeyListener.java
index 9a120d57c2c37..e427908541e54 100644
--- a/core/java/android/text/method/BaseKeyListener.java
+++ b/core/java/android/text/method/BaseKeyListener.java
@@ -345,7 +345,7 @@ public abstract class BaseKeyListener extends MetaKeyKeyListener
         }
 
         // Alt+Backspace or Alt+ForwardDelete deletes the current line, if possible.
-        if (isAltActive && deleteLine(view, content)) {
+        if (isAltActive && deleteLineFromCursor(view, content, isForwardDelete)) {
             return true;
         }
 
@@ -438,18 +438,34 @@ public abstract class BaseKeyListener extends MetaKeyKeyListener
         return false;
     }
 
-    private boolean deleteLine(View view, Editable content) {
+    private boolean deleteLineFromCursor(View view, Editable content, boolean forward) {
         if (view instanceof TextView) {
+            final int selectionStart = Selection.getSelectionStart(content);
+            final int selectionEnd = Selection.getSelectionEnd(content);
+            final int selectionMin;
+            final int selectionMax;
+            if (selectionStart < selectionEnd) {
+                selectionMin = selectionStart;
+                selectionMax = selectionEnd;
+            } else {
+                selectionMin = selectionEnd;
+                selectionMax = selectionStart;
+            }
+
             final TextView textView = (TextView) view;
             final Layout layout = textView.getLayout();
             if (layout != null && !textView.isOffsetMappingAvailable()) {
                 final int line = layout.getLineForOffset(Selection.getSelectionStart(content));
                 final int start = layout.getLineStart(line);
                 final int end = layout.getLineEnd(line);
-                if (end != start) {
-                    content.delete(start, end);
-                    return true;
+
+                if (forward) {
+                    content.delete(selectionMin, end);
+                } else {
+                    content.delete(start, selectionMax);
                 }
+
+                return true;
             }
         }
         return false;