Use user-history bigrams when no input if available.

This also fixes a small inconsistency upon clicking on whitespace
twice in a row.
Also add some unit tests for an introduced and an existing method.

Change-Id: I1be2fb53c9624f4d0f5299009632cb4384fdfc15

1 files changed, 4 insertions, 0 deletions

diff --git a/java/src/com/android/inputmethod/latin/UserBigramDictionary.java b/java/src/com/android/inputmethod/latin/UserBigramDictionary.java
index bb6642cd9..a32a6461a 100644
--- a/java/src/com/android/inputmethod/latin/UserBigramDictionary.java
+++ b/java/src/com/android/inputmethod/latin/UserBigramDictionary.java
@@ -162,6 +162,10 @@ public class UserBigramDictionary extends ExpandableDictionary {
         if (mIme != null && mIme.getCurrentWord().isAutoCapitalized()) {
             word2 = Character.toLowerCase(word2.charAt(0)) + word2.substring(1);
         }
+        // Do not insert a word as a bigram of itself
+        if (word1.equals(word2)) {
+            return 0;
+        }
 
         int freq = super.addBigram(word1, word2, FREQUENCY_FOR_TYPED);
         if (freq > FREQUENCY_MAX) freq = FREQUENCY_MAX;