Fix two nasty bugs with surrogate pairs.

The important bug is in findWordInTree. The problem, which is
not obvious, is that we were calling codePointAt() with the
code point index in the string, instead of the char index.
The other bug this change fixes was harmless in the practice,
because it's in the iteration which is only used for debug and
pretty printing purposes. It's very similar in that it would
substract a length in code point to a length in chars and
truncate a StringBuilder at that length, so it would fail in a
quite similar manner. This changes the meaning of the "length"
attribute in Position, but it's clearer this way anyway.

Bug: 8450145
Change-Id: If396f883a9e6449de39351553ba83f5be5bd30f0

1 files changed, 14 insertions, 14 deletions

diff --git a/tests/src/com/android/inputmethod/latin/makedict/BinaryDictIOTests.java b/tests/src/com/android/inputmethod/latin/makedict/BinaryDictIOTests.java
index ade010981..bd8729203 100644
--- a/tests/src/com/android/inputmethod/latin/makedict/BinaryDictIOTests.java
+++ b/tests/src/com/android/inputmethod/latin/makedict/BinaryDictIOTests.java
@@ -72,15 +72,12 @@ public class BinaryDictIOTests extends AndroidTestCase {
     private static final FormatSpec.FormatOptions VERSION3_WITH_DYNAMIC_UPDATE =
             new FormatSpec.FormatOptions(3, true /* supportsDynamicUpdate */);
 
-    private static final String[] CHARACTERS = {
-        "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m",
-        "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z"
-    };
-
     public BinaryDictIOTests() {
         super();
 
-        final Random random = new Random(123456);
+        final long time = System.currentTimeMillis();
+        Log.e(TAG, "Testing dictionary: seed is " + time);
+        final Random random = new Random(time);
         sWords.clear();
         generateWords(MAX_UNIGRAMS, random);
 
@@ -132,13 +129,16 @@ public class BinaryDictIOTests extends AndroidTestCase {
     /**
      * Generates a random word.
      */
-    private String generateWord(final int value) {
-        final int lengthOfChars = CHARACTERS.length;
+    private String generateWord(final Random random) {
         StringBuilder builder = new StringBuilder("a");
-        long lvalue = Math.abs((long)value);
-        while (lvalue > 0) {
-            builder.append(CHARACTERS[(int)(lvalue % lengthOfChars)]);
-            lvalue /= lengthOfChars;
+        int count = random.nextInt() % 30; // Arbitrarily 30 chars max
+        while (count > 0) {
+            final long r = Math.abs(random.nextInt());
+            if (r < 0) continue;
+            // Don't insert 0~20, but insert any other code point.
+            // Code points are in the range 0~0x10FFFF.
+            builder.appendCodePoint((int)(20 + r % (0x10FFFF - 20)));
+            --count;
         }
         return builder.toString();
     }
@@ -146,7 +146,7 @@ public class BinaryDictIOTests extends AndroidTestCase {
     private void generateWords(final int number, final Random random) {
         final Set<String> wordSet = CollectionUtils.newHashSet();
         while (wordSet.size() < number) {
-            wordSet.add(generateWord(random.nextInt()));
+            wordSet.add(generateWord(random));
         }
         sWords.addAll(wordSet);
     }
@@ -555,7 +555,7 @@ public class BinaryDictIOTests extends AndroidTestCase {
         // Test a word that isn't contained within the dictionary.
         final Random random = new Random((int)System.currentTimeMillis());
         for (int i = 0; i < 1000; ++i) {
-            final String word = generateWord(random.nextInt());
+            final String word = generateWord(random);
             if (sWords.indexOf(word) != -1) continue;
             runGetTerminalPosition(buffer, word, i, false);
         }