[PATCH v6 0/4] box: JSON tree class

[Kirill Shcherbatov <kshcherbatov@tarantool.org>]

http://github.com/tarantool/tarantool/tree/kshch/gh-1012-json-tree
https://github.com/tarantool/tarantool/issues/1012

Preparatory patch set for JSON indexes story.
Implemented JSON tree class is used for organizing JSON tokens
produced by a lexer in a tree-like structure reflecting a JSON
document structure.
Refactored json_lexer class to use index_base to emmit tokens
being ready to insert in JSON tree.
Refactored tuple_format to use the tree JSON class for working
with first-level fields to works with all fields in unified way.
Introduced help routines json_path_validate and json_path_cmp.

The third path "box: manage format fields with JSON tree class"
triggers a bug #3772 that is already on review
kshch/gh-3772-dirty-memory-access. Source branch has
cherry-picked fix.

General information of difference from previous version of
patch-set:
- new patch "make index_base support for json_lexer" allows to
  do not carry for LUA index base during token insertion
- significantly improved comments, many minor refactoring
- new consistency assertions, e.g. that no fields attached during
  token detach.
- reworked iterators
- _slowpath version for json_tree_lookup to improve performance
  for numerical levels
- new tests
- reworked json_path_cmp, introduced json_path_validate
- rebased on up-to-date 2.1 and cherry-picked #3772 fix

Kirill Shcherbatov (4):
  lib: make index_base support for json_lexer
  lib: implement JSON tree class for json library
  box: manage format fields with JSON tree class
  lib: introduce json_path_cmp, json_path_validate

 src/box/sql.c               |  18 +-
 src/box/sql/build.c         |   5 +-
 src/box/tuple.c             |  10 +-
 src/box/tuple_format.c      | 138 +++++++++------
 src/box/tuple_format.h      |  49 +++++-
 src/box/vy_stmt.c           |   4 +-
 src/lib/json/CMakeLists.txt |   1 +
 src/lib/json/json.c         | 290 +++++++++++++++++++++++++++++++-
 src/lib/json/json.h         | 326 +++++++++++++++++++++++++++++++++++-
 test/engine/tuple.result    |   4 +-
 test/unit/json_path.c       | 302 +++++++++++++++++++++++++++++++--
 test/unit/json_path.result  |  92 ++++++++--
 12 files changed, 1141 insertions(+), 98 deletions(-)

-- 
2.19.2