Update unit test for beginning-of-sentence.

Bug: 14119293
Change-Id: I594a1ca1096f0c12c678dd30eb75de905e55c5bb

1 files changed, 18 insertions, 1 deletions

diff --git a/native/jni/src/suggest/policyimpl/dictionary/structure/backward/v402/ver4_patricia_trie_policy.cpp b/native/jni/src/suggest/policyimpl/dictionary/structure/backward/v402/ver4_patricia_trie_policy.cpp
index e571d8986..805820b05 100644
--- a/native/jni/src/suggest/policyimpl/dictionary/structure/backward/v402/ver4_patricia_trie_policy.cpp
+++ b/native/jni/src/suggest/policyimpl/dictionary/structure/backward/v402/ver4_patricia_trie_policy.cpp
@@ -256,7 +256,24 @@ bool Ver4PatriciaTriePolicy::addNgramEntry(const PrevWordsInfo *const prevWordsI
             false /* tryLowerCaseSearch */);
     // TODO: Support N-gram.
     if (prevWordsPtNodePos[0] == NOT_A_DICT_POS) {
-        return false;
+        if (prevWordsInfo->isNthPrevWordBeginningOfSentence(1 /* n */)) {
+            const std::vector<UnigramProperty::ShortcutProperty> shortcuts;
+            const UnigramProperty beginningOfSentenceUnigramProperty(
+                    true /* representsBeginningOfSentence */, true /* isNotAWord */,
+                    false /* isBlacklisted */, MAX_PROBABILITY /* probability */,
+                    NOT_A_TIMESTAMP /* timestamp */, 0 /* level */, 0 /* count */, &shortcuts);
+            if (!addUnigramEntry(prevWordsInfo->getNthPrevWordCodePoints(1 /* n */),
+                    prevWordsInfo->getNthPrevWordCodePointCount(1 /* n */),
+                    &beginningOfSentenceUnigramProperty)) {
+                AKLOGE("Cannot add unigram entry for the beginning-of-sentence.");
+                return false;
+            }
+            // Refresh Terminal PtNode positions.
+            prevWordsInfo->getPrevWordsTerminalPtNodePos(this, prevWordsPtNodePos,
+                    false /* tryLowerCaseSearch */);
+        } else {
+            return false;
+        }
     }
     const int word1Pos = getTerminalPtNodePositionOfWord(
             bigramProperty->getTargetCodePoints()->data(),