Merge "[API Abuse - Text Consistency] Eliminate zero width, invisible formatting chars and consecutive spaces" into main

5 files changed, 275 insertions, 114 deletions

diff --git a/core/java/android/app/Notification.java b/core/java/android/app/Notification.java
index 329fb00c1d9b..fc3bb0288d67 100644
--- a/core/java/android/app/Notification.java
+++ b/core/java/android/app/Notification.java
@@ -114,7 +114,7 @@ import com.android.internal.annotations.VisibleForTesting;
 import com.android.internal.graphics.ColorUtils;
 import com.android.internal.util.ArrayUtils;
 import com.android.internal.util.ContrastColorUtil;
-import com.android.internal.util.NewlineNormalizer;
+import com.android.internal.util.NotificationBigTextNormalizer;
 
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
@@ -3262,12 +3262,12 @@ public class Notification implements Parcelable
         return cs.toString();
     }
 
-    private static CharSequence cleanUpNewLines(@Nullable CharSequence charSequence) {
+    private static CharSequence normalizeBigText(@Nullable CharSequence charSequence) {
         if (charSequence == null) {
             return charSequence;
         }
 
-        return NewlineNormalizer.normalizeNewlines(charSequence.toString());
+        return NotificationBigTextNormalizer.normalizeBigText(charSequence.toString());
     }
 
     private static CharSequence removeTextSizeSpans(CharSequence charSequence) {
@@ -8566,7 +8566,7 @@ public class Notification implements Parcelable
             // Replace the text with the big text, but only if the big text is not empty.
             CharSequence bigTextText = mBuilder.processLegacyText(mBigText);
             if (Flags.cleanUpSpansAndNewLines()) {
-                bigTextText = cleanUpNewLines(stripStyling(bigTextText));
+                bigTextText = normalizeBigText(stripStyling(bigTextText));
             }
             if (!TextUtils.isEmpty(bigTextText)) {
                 p.text(bigTextText);
diff --git a/core/java/com/android/internal/util/NewlineNormalizer.java b/core/java/com/android/internal/util/NewlineNormalizer.java
deleted file mode 100644
index 0104d1f56f83..000000000000
--- a/core/java/com/android/internal/util/NewlineNormalizer.java
+++ /dev/null
@@ -1,39 +0,0 @@
-/*
- * Copyright (C) 2024 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package com.android.internal.util;
-
-
-import java.util.regex.Pattern;
-
-/**
- * Utility class that replaces consecutive empty lines with single new line.
- * @hide
- */
-public class NewlineNormalizer {
-
-    private static final Pattern MULTIPLE_NEWLINES = Pattern.compile("\\v(\\s*\\v)?");
-
-    // Private constructor to prevent instantiation
-    private NewlineNormalizer() {}
-
-    /**
-     * Replaces consecutive newlines with a single newline in the input text.
-     */
-    public static String normalizeNewlines(String text) {
-        return MULTIPLE_NEWLINES.matcher(text).replaceAll("\n");
-    }
-}
diff --git a/core/java/com/android/internal/util/NotificationBigTextNormalizer.java b/core/java/com/android/internal/util/NotificationBigTextNormalizer.java
new file mode 100644
index 000000000000..80d409500ef0
--- /dev/null
+++ b/core/java/com/android/internal/util/NotificationBigTextNormalizer.java
@@ -0,0 +1,123 @@
+/*
+ * Copyright (C) 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.internal.util;
+
+
+import android.annotation.NonNull;
+import android.os.Trace;
+
+import java.util.regex.Pattern;
+
+/**
+ * Utility class that normalizes BigText style Notification content.
+ * @hide
+ */
+public class NotificationBigTextNormalizer {
+
+    private static final Pattern MULTIPLE_NEWLINES = Pattern.compile("\\v(\\s*\\v)?");
+    private static final Pattern HORIZONTAL_WHITESPACES = Pattern.compile("\\h+");
+
+    // Private constructor to prevent instantiation
+    private NotificationBigTextNormalizer() {}
+
+    /**
+     * Normalizes the given text by collapsing consecutive new lines into single one and cleaning
+     * up each line by removing zero-width characters, invisible formatting characters, and
+     * collapsing consecutive whitespace into single space.
+     */
+    @NonNull
+    public static String normalizeBigText(@NonNull String text) {
+        try {
+            Trace.beginSection("NotifBigTextNormalizer#normalizeBigText");
+            text = MULTIPLE_NEWLINES.matcher(text).replaceAll("\n");
+            text = HORIZONTAL_WHITESPACES.matcher(text).replaceAll(" ");
+            text = normalizeLines(text);
+            return text;
+        } finally {
+            Trace.endSection();
+        }
+    }
+
+    /**
+     * Normalizes lines in a text by removing zero-width characters, invisible formatting
+     * characters, and collapsing consecutive whitespace into single space.
+     *
+     * <p>
+     * This method processes the input text line by line. It eliminates zero-width
+     * characters (U+200B to U+200D, U+FEFF, U+034F), invisible formatting
+     * characters (U+2060 to U+2065, U+206A to U+206F, U+FFF9 to U+FFFB),
+     * and replaces any sequence of consecutive whitespace characters with a single space.
+     * </p>
+     *
+     * <p>
+     * Additionally, the method trims trailing whitespace from each line and removes any
+     * resulting empty lines.
+     * </p>
+     */
+    @NonNull
+    private static String normalizeLines(@NonNull String text) {
+        String[] lines = text.split("\n");
+        final StringBuilder textSB = new StringBuilder(text.length());
+        for (int i = 0; i < lines.length; i++) {
+            final String line = lines[i];
+            final StringBuilder lineSB = new StringBuilder(line.length());
+            boolean spaceSeen = false;
+            for (int j = 0; j < line.length(); j++) {
+                final char character = line.charAt(j);
+
+                // Skip ZERO WIDTH characters
+                if ((character >= '\u200B' && character <= '\u200D')
+                        || character == '\uFEFF' || character == '\u034F') {
+                    continue;
+                }
+                // Skip INVISIBLE_FORMATTING_CHARACTERS
+                if ((character >= '\u2060' && character <= '\u2065')
+                        || (character >= '\u206A' && character <= '\u206F')
+                        || (character >= '\uFFF9' && character <= '\uFFFB')) {
+                    continue;
+                }
+
+                if (isSpace(character)) {
+                    // eliminate consecutive spaces....
+                    if (!spaceSeen) {
+                        lineSB.append(" ");
+                    }
+                    spaceSeen = true;
+                } else {
+                    spaceSeen = false;
+                    lineSB.append(character);
+                }
+            }
+            // trim line.
+            final String currentLine = lineSB.toString().trim();
+
+            // don't add empty lines after trim.
+            if (currentLine.length() > 0) {
+                if (textSB.length() > 0) {
+                    textSB.append("\n");
+                }
+                textSB.append(currentLine);
+            }
+        }
+
+        return textSB.toString();
+    }
+
+    private static boolean isSpace(char ch) {
+        return ch != '\n' && Character.isSpaceChar(ch);
+    }
+}
diff --git a/core/tests/utiltests/src/com/android/internal/util/NewlineNormalizerTest.java b/core/tests/utiltests/src/com/android/internal/util/NewlineNormalizerTest.java
deleted file mode 100644
index bcdac610a49d..000000000000
--- a/core/tests/utiltests/src/com/android/internal/util/NewlineNormalizerTest.java
+++ /dev/null
@@ -1,71 +0,0 @@
-/*
- * Copyright (C) 2024 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package com.android.internal.util;
-
-import static junit.framework.Assert.assertEquals;
-
-
-import android.platform.test.annotations.DisabledOnRavenwood;
-import android.platform.test.ravenwood.RavenwoodRule;
-
-import androidx.test.runner.AndroidJUnit4;
-
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-
-/**
- * Test for {@link NewlineNormalizer}
- * @hide
- */
-@DisabledOnRavenwood(blockedBy = NewlineNormalizer.class)
-@RunWith(AndroidJUnit4.class)
-public class NewlineNormalizerTest {
-
-    @Rule
-    public final RavenwoodRule mRavenwood = new RavenwoodRule();
-
-    @Test
-    public void testEmptyInput() {
-        assertEquals("", NewlineNormalizer.normalizeNewlines(""));
-    }
-
-    @Test
-    public void testSingleNewline() {
-        assertEquals("\n", NewlineNormalizer.normalizeNewlines("\n"));
-    }
-
-    @Test
-    public void testMultipleConsecutiveNewlines() {
-        assertEquals("\n", NewlineNormalizer.normalizeNewlines("\n\n\n\n\n"));
-    }
-
-    @Test
-    public void testNewlinesWithSpacesAndTabs() {
-        String input = "Line 1\n  \n \t \n\tLine 2";
-        // Adjusted expected output to include the tab character
-        String expected = "Line 1\n\tLine 2";
-        assertEquals(expected, NewlineNormalizer.normalizeNewlines(input));
-    }
-
-    @Test
-    public void testMixedNewlineCharacters() {
-        String input = "Line 1\r\nLine 2\u000BLine 3\fLine 4\u2028Line 5\u2029Line 6";
-        String expected = "Line 1\nLine 2\nLine 3\nLine 4\nLine 5\nLine 6";
-        assertEquals(expected, NewlineNormalizer.normalizeNewlines(input));
-    }
-}
diff --git a/core/tests/utiltests/src/com/android/internal/util/NotificationBigTextNormalizerTest.java b/core/tests/utiltests/src/com/android/internal/util/NotificationBigTextNormalizerTest.java
new file mode 100644
index 000000000000..1f2e24aa8c68
--- /dev/null
+++ b/core/tests/utiltests/src/com/android/internal/util/NotificationBigTextNormalizerTest.java
@@ -0,0 +1,148 @@
+/*
+ * Copyright (C) 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.internal.util;
+
+import static junit.framework.Assert.assertEquals;
+
+
+import android.platform.test.annotations.DisabledOnRavenwood;
+import android.platform.test.ravenwood.RavenwoodRule;
+
+import androidx.test.runner.AndroidJUnit4;
+
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+/**
+ * Test for {@link NotificationBigTextNormalizer}
+ * @hide
+ */
+@DisabledOnRavenwood(blockedBy = NotificationBigTextNormalizer.class)
+@RunWith(AndroidJUnit4.class)
+public class NotificationBigTextNormalizerTest {
+
+    @Rule
+    public final RavenwoodRule mRavenwood = new RavenwoodRule();
+
+
+    @Test
+    public void testEmptyInput() {
+        assertEquals("", NotificationBigTextNormalizer.normalizeBigText(""));
+    }
+
+    @Test
+    public void testSingleNewline() {
+        assertEquals("", NotificationBigTextNormalizer.normalizeBigText("\n"));
+    }
+
+    @Test
+    public void testMultipleConsecutiveNewlines() {
+        assertEquals("", NotificationBigTextNormalizer.normalizeBigText("\n\n\n\n\n"));
+    }
+
+    @Test
+    public void testNewlinesWithSpacesAndTabs() {
+        String input = "Line 1\n  \n \t \n\tLine 2";
+        // Adjusted expected output to include the tab character
+        String expected = "Line 1\nLine 2";
+        assertEquals(expected, NotificationBigTextNormalizer.normalizeBigText(input));
+    }
+
+    @Test
+    public void testMixedNewlineCharacters() {
+        String input = "Line 1\r\nLine 2\u000BLine 3\fLine 4\u2028Line 5\u2029Line 6";
+        String expected = "Line 1\nLine 2\nLine 3\nLine 4\nLine 5\nLine 6";
+        assertEquals(expected, NotificationBigTextNormalizer.normalizeBigText(input));
+    }
+
+    @Test
+    public void testConsecutiveSpaces() {
+        // Only spaces
+        assertEquals("This is a test.", NotificationBigTextNormalizer.normalizeBigText("This"
+                + "              is   a                         test."));
+        // Zero width characters bw spaces.
+        assertEquals("This is a test.", NotificationBigTextNormalizer.normalizeBigText("This"
+                + "\u200B \u200B \u200B \u200B \u200B \u200B \u200B \u200Bis\uFEFF \uFEFF \uFEFF"
+                + " \uFEFFa \u034F \u034F \u034F \u034F \u034F \u034Ftest."));
+
+        // Invisible formatting characters bw spaces.
+        assertEquals("This is a test.", NotificationBigTextNormalizer.normalizeBigText("This"
+                + "\u2061 \u2061 \u2061 \u2061 \u2061 \u2061 \u2061 \u2061is\u206E \u206E \u206E"
+                + " \u206Ea \uFFFB \uFFFB \uFFFB \uFFFB \uFFFB \uFFFBtest."));
+        // Non breakable spaces
+        assertEquals("This is a test.", NotificationBigTextNormalizer.normalizeBigText("This"
+                + "\u00A0\u00A0\u00A0\u00A0\u00A0\u00A0is\u2005 \u2005 \u2005"
+                + " \u2005a\u2005\u2005\u2005 \u2005\u2005\u2005test."));
+    }
+
+    @Test
+    public void testZeroWidthCharRemoval() {
+        // Test each character individually
+        char[] zeroWidthChars = { '\u200B', '\u200C', '\u200D', '\uFEFF', '\u034F' };
+
+        for (char c : zeroWidthChars) {
+            String input = "Test" + c + "string";
+            String expected = "Teststring";
+            assertEquals(expected, NotificationBigTextNormalizer.normalizeBigText(input));
+        }
+    }
+
+    @Test
+    public void testWhitespaceReplacement() {
+        assertEquals("This text has horizontal whitespace.",
+                NotificationBigTextNormalizer.normalizeBigText(
+                        "This\ttext\thas\thorizontal\twhitespace."));
+        assertEquals("This text has mixed whitespace.",
+                NotificationBigTextNormalizer.normalizeBigText(
+                        "This  text  has \u00A0 mixed\u2009whitespace."));
+        assertEquals("This text has leading and trailing whitespace.",
+                NotificationBigTextNormalizer.normalizeBigText(
+                        "\t This text has leading and trailing whitespace. \n"));
+    }
+
+    @Test
+    public void testInvisibleFormattingCharacterRemoval() {
+        // Test each character individually
+        char[] invisibleFormattingChars = {
+                '\u2060', '\u2061', '\u2062', '\u2063', '\u2064', '\u2065',
+                '\u206A', '\u206B', '\u206C', '\u206D', '\u206E', '\u206F',
+                '\uFFF9', '\uFFFA', '\uFFFB'
+        };
+
+        for (char c : invisibleFormattingChars) {
+            String input = "Test " + c + "string";
+            String expected = "Test string";
+            assertEquals(expected, NotificationBigTextNormalizer.normalizeBigText(input));
+        }
+    }
+    @Test
+    public void testNonBreakSpaceReplacement() {
+        // Test each character individually
+        char[] nonBreakSpaces = {
+                '\u00A0', '\u1680', '\u2000', '\u2001', '\u2002',
+                '\u2003', '\u2004', '\u2005', '\u2006', '\u2007',
+                '\u2008', '\u2009', '\u200A', '\u202F', '\u205F', '\u3000'
+        };
+
+        for (char c : nonBreakSpaces) {
+            String input = "Test" + c + "string";
+            String expected = "Test string";
+            assertEquals(expected, NotificationBigTextNormalizer.normalizeBigText(input));
+        }
+    }
+}