message: add test for phrase search on multi text field
diff: @@ -1619,6 +1619,7 @@ mod tests {
  );
  let large_text_field = schema_builder.add_text_field("large_text_field", TEXT | STORED);
  + let multi_text_fields = schema_builder.add_text_field("multi_text_fields", TEXT | STORED);
  let multi_numbers = schema_builder.add_u64_field(
  "multi_numbers",
  @@ -1658,6 +1659,12 @@ mod tests {
  let ip_exists = |id| id % 3 != 0; // 0 does not exist
  + let multi_text_field_text1 = "test1 test2 test3 test1 test2 test3";
  + // rotate left
  + let multi_text_field_text2 = "test2 test3 test1 test2 test3 test1";
  + // rotate right
  + let multi_text_field_text3 = "test3 test1 test2 test3 test1 test2";
  +
  for &op in ops {
  match op {
  IndexingOp::AddDoc { id } => {
  @@ -1678,7 +1685,10 @@ mod tests {
  multi_bools => (id % 2u64) == 0,
  text_field => id.to_string(),
  facet_field => facet,
  - large_text_field=> LOREM
  + large_text_field => LOREM,
  + multi_text_fields => multi_text_field_text1,
  + multi_text_fields => multi_text_field_text2,
  + multi_text_fields => multi_text_field_text3,
  ))?;
  } else {
  index_writer.add_document(doc!(id_field=>id,
  @@ -1696,7 +1706,10 @@ mod tests {
  multi_bools => (id % 2u64) == 0,
  text_field => id.to_string(),
  facet_field => facet,
  - large_text_field=> LOREM
  + large_text_field => LOREM,
  + multi_text_fields => multi_text_field_text1,
  + multi_text_fields => multi_text_field_text2,
  + multi_text_fields => multi_text_field_text3,
  ))?;
  }
  }
  @@ -1922,11 +1935,21 @@ mod tests {
  for (existing_id, count) in &expected_ids_and_num_occurrences {
  let (existing_id, count) = (*existing_id, *count);
  - let assert_field = |field| do_search(&existing_id.to_string(), field).len() as u64;
  - assert_eq!(assert_field(text_field), count);
  - assert_eq!(assert_field(i64_field), count);
  - assert_eq!(assert_field(f64_field), count);
  - assert_eq!(assert_field(id_field), count);
  + let get_num_hits = |field| do_search(&existing_id.to_string(), field).len() as u64;
  + assert_eq!(get_num_hits(text_field), count);
  + assert_eq!(get_num_hits(i64_field), count);
  + assert_eq!(get_num_hits(f64_field), count);
  + assert_eq!(get_num_hits(id_field), count);
  +
  + // Test multi text
  + assert_eq!(
  + do_search("\"test1 test2\"", multi_text_fields).len(),
  + num_docs_expected
  + );
  + assert_eq!(
  + do_search("\"test2 test3\"", multi_text_fields).len(),
  + num_docs_expected
  + );
  // Test bytes
  let term = Term::from_field_bytes(bytes_field, existing_id.to_le_bytes().as_slice());
  