fix bug in trie

lib/util/trie.js

@@ -183,6 +183,9 @@ const __suggest = (trie, path, remaining, maxSuggestions) => {
   }
 
   const [pos, prefix] = binarySearch(trie.children, remaining);
+  if (prefix.length === 0) {
+    return []; // nothing in common
+  }
   if (pos < trie.children.length) {
     const [haveKey, haveChildNode] = trie.children[pos];
     return __suggest(haveChildNode, path+haveKey, remaining.slice(haveKey.length), maxSuggestions);

tests/trie.js

@@ -90,3 +90,13 @@ assert.equal(
   true,
   "trie should always be properly sorted!"
 );
+
+assert.equal(
+  growPrefix(bigTrie)("dict.le"),
+  "ngth"
+);
+
+assert.deepEqual(
+  suggest(bigTrie)("ooo")(2),
+  []
+);