From d54f486fe66d01450d3c7a04fb0a025319a3014c Mon Sep 17 00:00:00 2001
From: Daniel Leong <daniel.leong@discordapp.com>
Date: Sun, 4 Jun 2023 00:03:01 -0700
Subject: [PATCH] Fix: a11y crash when an accessible link is ellipsized away
 (#37050)
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Summary:
If an accessible link is ellipsized out of being rendered, the AccessibilityDelegate will still attempt to populate an accessibility node for it; doing so results in an invalid request to a TextLayout API, however, causing a crash. This crash occurs as soon as the element is rendered, so long as a Screen Reader (or app using similar a11y APIs) is enabled. This change uses a technique similar to those existing to make the node "blank" in such cases, so Talkback can filter it out—and, more importantly, not crash.

## Changelog:

[Android] [Fixed] - Fix links hidden via ellipsis crashing screen readers

Pull Request resolved: https://github.com/facebook/react-native/pull/37050

Test Plan:
- Added a block to the "Accessibility Android APIs" page in the rn-tester app. Without the changes to `ReactAccessibilityDelegate`, this component crashes the app; with the changes, the component renders without problem.
- You can also see the crash "in the wild" using [this Expo Snack](https://snack.expo.dev/dhleong/2d1407) that I put together when trying to isolate this issue.

Reviewed By: rshest

Differential Revision: D46206673

Pulled By: NickGerleman

fbshipit-source-id: 0eb3e735202ee6be5f931bbb4bb92c24e7458ea6
---
 .../uimanager/ReactAccessibilityDelegate.java | 25 ++++++++++++++++---
 .../AccessibilityAndroidExample.android.js    | 14 +++++++++++
 2 files changed, 35 insertions(+), 4 deletions(-)

diff --git a/packages/react-native/ReactAndroid/src/main/java/com/facebook/react/uimanager/ReactAccessibilityDelegate.java b/packages/react-native/ReactAndroid/src/main/java/com/facebook/react/uimanager/ReactAccessibilityDelegate.java
index 531e4591ba6..b8b08c9bf74 100644
--- a/packages/react-native/ReactAndroid/src/main/java/com/facebook/react/uimanager/ReactAccessibilityDelegate.java
+++ b/packages/react-native/ReactAndroid/src/main/java/com/facebook/react/uimanager/ReactAccessibilityDelegate.java
@@ -786,9 +786,18 @@ public class ReactAccessibilityDelegate extends ExploreByTouchHelper {
       return;
     }
 
+    // NOTE: The span may not actually have visible bounds within its parent,
+    // due to line limits, etc.
+    final Rect bounds = getBoundsInParent(accessibleTextSpan);
+    if (bounds == null) {
+      node.setContentDescription("");
+      node.setBoundsInParent(new Rect(0, 0, 1, 1));
+      return;
+    }
+
     node.setContentDescription(accessibleTextSpan.description);
     node.addAction(AccessibilityNodeInfoCompat.ACTION_CLICK);
-    node.setBoundsInParent(getBoundsInParent(accessibleTextSpan));
+    node.setBoundsInParent(bounds);
     node.setRoleDescription(mView.getResources().getString(R.string.link_description));
     node.setClassName(AccessibilityRole.getValue(AccessibilityRole.BUTTON));
   }
@@ -805,10 +814,19 @@ public class ReactAccessibilityDelegate extends ExploreByTouchHelper {
       return new Rect(0, 0, textView.getWidth(), textView.getHeight());
     }
 
-    Rect rootRect = new Rect();
-
     double startOffset = accessibleLink.start;
     double endOffset = accessibleLink.end;
+
+    // Ensure the link hasn't been ellipsized away; in such cases,
+    // getPrimaryHorizontal will crash (and the link isn't rendered anyway).
+    int startOffsetLineNumber = textViewLayout.getLineForOffset((int) startOffset);
+    int lineEndOffset = textViewLayout.getLineEnd(startOffsetLineNumber);
+    if (startOffset > lineEndOffset) {
+      return null;
+    }
+
+    Rect rootRect = new Rect();
+
     double startXCoordinates = textViewLayout.getPrimaryHorizontal((int) startOffset);
 
     final Paint paint = new Paint();
@@ -818,7 +836,6 @@ public class ReactAccessibilityDelegate extends ExploreByTouchHelper {
     paint.setTextSize(textSize);
     int textWidth = (int) Math.ceil(paint.measureText(accessibleLink.description));
 
-    int startOffsetLineNumber = textViewLayout.getLineForOffset((int) startOffset);
     int endOffsetLineNumber = textViewLayout.getLineForOffset((int) endOffset);
     boolean isMultiline = startOffsetLineNumber != endOffsetLineNumber;
     textViewLayout.getLineBounds(startOffsetLineNumber, rootRect);
diff --git a/packages/rn-tester/js/examples/Accessibility/AccessibilityAndroidExample.android.js b/packages/rn-tester/js/examples/Accessibility/AccessibilityAndroidExample.android.js
index 2daf0ba27c6..f5da9efc20e 100644
--- a/packages/rn-tester/js/examples/Accessibility/AccessibilityAndroidExample.android.js
+++ b/packages/rn-tester/js/examples/Accessibility/AccessibilityAndroidExample.android.js
@@ -65,6 +65,20 @@ class AccessibilityAndroidExample extends React.Component<
   render(): React.Node {
     return (
       <RNTesterPage title={'Accessibility Android APIs'}>
+        <RNTesterBlock title="Ellipsized Accessible Links">
+          <Text numberOfLines={3}>
+            <Text>
+              Bacon {this.state.count} Ipsum{'\n'}
+            </Text>
+            <Text>Dolor sit amet{'\n'}</Text>
+            <Text>Eggsecetur{'\n'}</Text>
+            <Text>{'\n'}</Text>
+            <Text accessibilityRole="link" onPress={this._addOne}>
+              http://github.com
+            </Text>
+          </Text>
+        </RNTesterBlock>
+
         <RNTesterBlock title="LiveRegion">
           <TouchableWithoutFeedback onPress={this._addOne}>
             <View style={styles.embedded}>