fix: .phrase_query() not working (#2781)

The `self._query` value was not set when wrapping its copy `query` with
quotation marks.

The test for phrase queries has been updated to test the
`.phrase_query()` method as well, which will catch this bug.

---------

Co-authored-by: Will Jones <willjones127@gmail.com>

python/python/lancedb/query.py

@@ -1495,7 +1495,7 @@ class LanceFtsQueryBuilder(LanceQueryBuilder):
         if self._phrase_query:
             if isinstance(query, str):
                 if not query.startswith('"') or not query.endswith('"'):
-                    query = f'"{query}"'
+                    self._query = f'"{query}"'
             elif isinstance(query, FullTextQuery) and not isinstance(
                 query, PhraseQuery
             ):

python/python/tests/test_fts.py

@@ -325,11 +325,18 @@ def test_search_fts_phrase_query(table):
         pass
     table.create_fts_index("text", use_tantivy=False, with_position=True, replace=True)
     results = table.search("puppy").limit(100).to_list()
+
+    # Test with quotation marks
     phrase_results = table.search('"puppy runs"').limit(100).to_list()
     assert len(results) > len(phrase_results)
     assert len(phrase_results) > 0
 
-    # Test with a query
+    # Test with .phrase_query()
+    phrase_results = table.search("puppy runs").phrase_query().limit(100).to_list()
+    assert len(results) > len(phrase_results)
+    assert len(phrase_results) > 0
+
+    # Test with PhraseQuery()
     phrase_results = (
         table.search(PhraseQuery("puppy runs", "text")).limit(100).to_list()
     )

python/python/tests/test_table.py

@@ -1487,7 +1487,7 @@ def setup_hybrid_search_table(db: DBConnection, embedding_func):
     table.add([{"text": p} for p in phrases])
 
     # Create a fts index
-    table.create_fts_index("text")
+    table.create_fts_index("text", with_position=True)
 
     return table, MyTable, emb