RESTRICT AUTOMERGE Do not linkify text with RLO/LRO characters.

Also don't show smart actions for selections in text with unsupported
characters.

Bug: 116321860
Test: atest android.view.textclassifier.TextClassificationManagerTest \
            android.text.util.cts.LinkifyTest \
	    android.text.util.LinkifyTest \
	    android.widget.TextViewActivityTest

Change-Id: I01b5e936aa4dfc937a98f50e9fc8171666861a61

6 files changed, 77 insertions, 2 deletions

diff --git a/core/java/android/text/util/Linkify.java b/core/java/android/text/util/Linkify.java
index c905f49569d7..dc68da0310b6 100644
--- a/core/java/android/text/util/Linkify.java
+++ b/core/java/android/text/util/Linkify.java
@@ -29,6 +29,7 @@ import android.text.Spanned;
 import android.text.method.LinkMovementMethod;
 import android.text.method.MovementMethod;
 import android.text.style.URLSpan;
+import android.util.Log;
 import android.util.Patterns;
 import android.view.textclassifier.TextClassifier;
 import android.view.textclassifier.TextLinks;
@@ -77,6 +78,9 @@ import java.util.regex.Pattern;
  */
 
 public class Linkify {
+
+    private static final String LOG_TAG = "Linkify";
+
     /**
      *  Bit field indicating that web URLs should be matched in methods that
      *  take an options mask
@@ -246,6 +250,11 @@ public class Linkify {
 
     private static boolean addLinks(@NonNull Spannable text, @LinkifyMask int mask,
             @Nullable Context context) {
+        if (text != null && containsUnsupportedCharacters(text.toString())) {
+            android.util.EventLog.writeEvent(0x534e4554, "116321860", -1, "");
+            return false;
+        }
+
         if (mask == 0) {
             return false;
         }
@@ -292,6 +301,29 @@ public class Linkify {
     }
 
     /**
+     * Returns true if the specified text contains at least one unsupported character for applying
+     * links. Also logs the error.
+     *
+     * @param text the text to apply links to
+     * @hide
+     */
+    public static boolean containsUnsupportedCharacters(String text) {
+        if (text.contains("\u202C")) {
+            Log.e(LOG_TAG, "Unsupported character for applying links: u202C");
+            return true;
+        }
+        if (text.contains("\u202D")) {
+            Log.e(LOG_TAG, "Unsupported character for applying links: u202D");
+            return true;
+        }
+        if (text.contains("\u202E")) {
+            Log.e(LOG_TAG, "Unsupported character for applying links: u202E");
+            return true;
+        }
+        return false;
+    }
+
+    /**
      *  Scans the text of the provided TextView and turns all occurrences of
      *  the link types indicated in the mask into clickable links.  If matches
      *  are found the movement method for the TextView is set to
@@ -461,6 +493,11 @@ public class Linkify {
     public static final boolean addLinks(@NonNull Spannable spannable, @NonNull Pattern pattern,
             @Nullable  String defaultScheme, @Nullable String[] schemes,
             @Nullable MatchFilter matchFilter, @Nullable TransformFilter transformFilter) {
+        if (spannable != null && containsUnsupportedCharacters(spannable.toString())) {
+            android.util.EventLog.writeEvent(0x534e4554, "116321860", -1, "");
+            return false;
+        }
+
         final String[] schemesCopy;
         if (defaultScheme == null) defaultScheme = "";
         if (schemes == null || schemes.length < 1) {
diff --git a/core/java/android/view/textclassifier/TextClassification.java b/core/java/android/view/textclassifier/TextClassification.java
index 9511a9efb3d5..49ca969fa7af 100644
--- a/core/java/android/view/textclassifier/TextClassification.java
+++ b/core/java/android/view/textclassifier/TextClassification.java
@@ -104,7 +104,7 @@ public final class TextClassification implements Parcelable {
     /**
      * @hide
      */
-    static final TextClassification EMPTY = new TextClassification.Builder().build();
+    public static final TextClassification EMPTY = new TextClassification.Builder().build();
 
     private static final String LOG_TAG = "TextClassification";
     // TODO(toki): investigate a way to derive this based on device properties.
diff --git a/core/java/android/view/textclassifier/TextLinksParams.java b/core/java/android/view/textclassifier/TextLinksParams.java
index be4c3bcdff67..c21206ca0258 100644
--- a/core/java/android/view/textclassifier/TextLinksParams.java
+++ b/core/java/android/view/textclassifier/TextLinksParams.java
@@ -107,6 +107,13 @@ public final class TextLinksParams {
         Preconditions.checkNotNull(textLinks);
 
         final String textString = text.toString();
+
+        if (Linkify.containsUnsupportedCharacters(textString)) {
+            // Do not apply links to text containing unsupported characters.
+            android.util.EventLog.writeEvent(0x534e4554, "116321860", -1, "");
+            return TextLinks.STATUS_NO_LINKS_APPLIED;
+        }
+
         if (!textString.startsWith(textLinks.getText())) {
             return TextLinks.STATUS_DIFFERENT_TEXT;
         }
diff --git a/core/java/android/widget/SelectionActionModeHelper.java b/core/java/android/widget/SelectionActionModeHelper.java
index 6cb0eaa7f47d..0d88e6986f11 100644
--- a/core/java/android/widget/SelectionActionModeHelper.java
+++ b/core/java/android/widget/SelectionActionModeHelper.java
@@ -31,6 +31,7 @@ import android.text.Layout;
 import android.text.Selection;
 import android.text.Spannable;
 import android.text.TextUtils;
+import android.text.util.Linkify;
 import android.util.Log;
 import android.view.ActionMode;
 import android.view.textclassifier.SelectionEvent;
@@ -1045,7 +1046,12 @@ public final class SelectionActionModeHelper {
 
                 trimText();
                 final TextClassification classification;
-                if (mContext.getApplicationInfo().targetSdkVersion >= Build.VERSION_CODES.P) {
+                if (Linkify.containsUnsupportedCharacters(mText)) {
+                    // Do not show smart actions for text containing unsupported characters.
+                    android.util.EventLog.writeEvent(0x534e4554, "116321860", -1, "");
+                    classification = TextClassification.EMPTY;
+                } else if (mContext.getApplicationInfo().targetSdkVersion
+                        >= Build.VERSION_CODES.P) {
                     final TextClassification.Request request =
                             new TextClassification.Request.Builder(
                                     mTrimmedText, mRelativeStart, mRelativeEnd)
diff --git a/core/tests/coretests/src/android/view/textclassifier/TextClassificationManagerTest.java b/core/tests/coretests/src/android/view/textclassifier/TextClassificationManagerTest.java
index c8a53cc86347..9015e92a4f08 100644
--- a/core/tests/coretests/src/android/view/textclassifier/TextClassificationManagerTest.java
+++ b/core/tests/coretests/src/android/view/textclassifier/TextClassificationManagerTest.java
@@ -39,6 +39,8 @@ import android.service.textclassifier.TextClassifierService;
 import android.support.test.InstrumentationRegistry;
 import android.support.test.filters.SmallTest;
 import android.support.test.runner.AndroidJUnit4;
+import android.text.Spannable;
+import android.text.SpannableString;
 
 import org.hamcrest.BaseMatcher;
 import org.hamcrest.Description;
@@ -307,6 +309,16 @@ public class TextClassificationManagerTest {
     }
 
     @Test
+    public void testApplyLinks_unsupportedCharacter() {
+        if (isTextClassifierDisabled()) return;
+        Spannable url = new SpannableString("\u202Emoc.diordna.com");
+        TextLinks.Request request = new TextLinks.Request.Builder(url).build();
+        assertEquals(
+                TextLinks.STATUS_NO_LINKS_APPLIED,
+                mClassifier.generateLinks(request).apply(url, 0, null));
+    }
+
+    @Test
     public void testSetTextClassifier() {
         TextClassifier classifier = mock(TextClassifier.class);
         mTcm.setTextClassifier(classifier);
diff --git a/core/tests/coretests/src/android/widget/TextViewActivityTest.java b/core/tests/coretests/src/android/widget/TextViewActivityTest.java
index 70dc6189c6c2..90758ba7c418 100644
--- a/core/tests/coretests/src/android/widget/TextViewActivityTest.java
+++ b/core/tests/coretests/src/android/widget/TextViewActivityTest.java
@@ -983,6 +983,19 @@ public class TextViewActivityTest {
     }
 
     @Test
+    public void testNoAssistItemForTextFieldWithUnsupportedCharacters() throws Throwable {
+        useSystemDefaultTextClassifier();
+        final String text = "\u202Emoc.diordna.com";
+        final TextView textView = mActivity.findViewById(R.id.textview);
+        mActivityRule.runOnUiThread(() -> textView.setText(text));
+        mInstrumentation.waitForIdleSync();
+
+        onView(withId(R.id.textview)).perform(longPressOnTextAtIndex(text.indexOf('.')));
+        sleepForFloatingToolbarPopup();
+        assertFloatingToolbarDoesNotContainItem(android.R.id.textAssist);
+    }
+
+    @Test
     public void testSelectionMetricsLogger_noAbandonAfterCopy() throws Throwable {
         final List<SelectionEvent> selectionEvents = new ArrayList<>();
         final TextClassifier classifier = new TextClassifier() {