Fix a test and crash with a better error message when reading

When there are too many bigrams, we stop reading the file,
so the file pointer is in an inconsistent place. This means we
have no idea what's going to happen next. It's better to crash
right away.

Change-Id: Id3b7b78cbe4fda3493b3c9c46758763e1ab5f6a3

java/src/com/android/inputmethod/latin/makedict/Ver3DictDecoder.java

@@ -169,7 +169,8 @@ public class Ver3DictDecoder extends DictDecoder {
             addressPointer += PtNodeReader.readBigramAddresses(mDictBuffer, bigrams, 
                     addressPointer);
             if (bigrams.size() >= FormatSpec.MAX_BIGRAMS_IN_A_PTNODE) {
-                MakedictLog.d("too many bigrams in a PtNode.");
+                throw new RuntimeException("Too many bigrams in a PtNode (" + bigrams.size()
+                        + " but max is " + FormatSpec.MAX_BIGRAMS_IN_A_PTNODE + ")");
             }
         } else {
             bigrams = null;

java/src/com/android/inputmethod/latin/makedict/Ver4DictDecoder.java

@@ -224,7 +224,8 @@ public class Ver4DictDecoder extends DictDecoder {
                 if (0 == (bigramFlags & FormatSpec.FLAG_BIGRAM_SHORTCUT_ATTR_HAS_NEXT)) break;
             }
             if (bigrams.size() >= FormatSpec.MAX_BIGRAMS_IN_A_PTNODE) {
-                MakedictLog.d("too many bigrams in a node.");
+                throw new RuntimeException("Too many bigrams in a PtNode (" + bigrams.size()
+                        + " but max is " + FormatSpec.MAX_BIGRAMS_IN_A_PTNODE + ")");
             }
         } else {
             bigrams = null;

tests/src/com/android/inputmethod/latin/makedict/BinaryDictDecoderEncoderTests.java

@@ -104,7 +104,9 @@ public class BinaryDictDecoderEncoderTests extends AndroidTestCase {
         }
 
         sStarBigrams.put(0, new ArrayList<Integer>());
-        for (int i = 1; i < sWords.size(); ++i) {
+        // MAX - 1 because we added one above already
+        final int maxBigrams = Math.min(sWords.size(), FormatSpec.MAX_BIGRAMS_IN_A_PTNODE - 1);
+        for (int i = 1; i < maxBigrams; ++i) {
             sStarBigrams.get(0).add(i);
         }