python-shogi: a pure Python shogi library

Introduction

This is the module for shogi written in Pure Python. It's based on python-chess commit 6203406259504cddf6f271e6a7b1e04ba0c96165.

This is the scholars mate in python-shogi:

>>> import shogi

>>> board = shogi.Board()

>>> board.push(shogi.Move.from_usi('7g7f'))

>>> board.push_usi('3c3d')
Move.from_usi('3c3d')
>>> board.push_usi('8h2b+')
Move.from_usi('8h2b+')
>>> board.push_usi('4a5b')
Move.from_usi('4a5b')
>>> board.push_usi('B*4b')
Move.from_usi('B*4b')
>>> board.push_usi('5a4a')
Move.from_usi('5a4a')
>>> board.push_usi('2b3a')
Move.from_usi('2b3a')
>>> board.is_checkmate()
True

Features

Supports Python 2.7 and Python 3.3+.
Supports standard shogi (hon shogi)

Legal move generator and move validation.

>>> shogi.Move.from_usi("5i5a") in board.legal_moves
False

Make and unmake moves.

>>> last_move = board.pop() # Unmake last move
>>> last_move
Move.from_usi('2b3a')

>>> board.push(last_move) # Restore

Show a simple ASCII board.

>>> print(board)
 l  n  s  g  .  k +B  n  l
 .  r  .  .  g  B  .  .  .
 p  p  p  p  p  p  .  p  p
 .  .  .  .  .  .  p  .  .
 .  .  .  .  .  .  .  .  .
 .  .  P  .  .  .  .  .  .
 P  P  .  P  P  P  P  P  P
 .  .  .  .  .  .  .  R  .
 L  N  S  G  K  G  S  N  L
<BLANKLINE>
 S*1

Show a KIF style board.

>>> print(board.kif_str())
後手の持駒：
  ９ ８ ７ ６ ５ ４ ３ ２ １
+---------------------------+
|v香v桂v銀v金 ・v玉 馬v桂v香|一
| ・v飛 ・ ・v金 角 ・ ・ ・|二
|v歩v歩v歩v歩v歩v歩 ・v歩v歩|三
| ・ ・ ・ ・ ・ ・v歩 ・ ・|四
| ・ ・ ・ ・ ・ ・ ・ ・ ・|五
| ・ ・ 歩 ・ ・ ・ ・ ・ ・|六
| 歩 歩 ・ 歩 歩 歩 歩 歩 歩|七
| ・ ・ ・ ・ ・ ・ ・ 飛 ・|八
| 香 桂 銀 金 玉 金 銀 桂 香|九
+---------------------------+
先手の持駒： 銀

Detects checkmates, stalemates.

>>> board.is_stalemate()
False
>>> board.is_game_over()
True

Detects repetitions. Has a half move clock.

>>> board.is_fourfold_repetition()
False
>>> board.move_number
8

Detects checks and attacks.

>>> board.is_check()
True
>>> board.is_attacked_by(shogi.BLACK, shogi.A4)
True
>>> attackers = board.attackers(shogi.BLACK, shogi.H5)
>>> attackers
SquareSet(0b111000010000000000000000000000000000000000000000000000000000000000000000000000)
>>> shogi.H2 in attackers
True
>>> print(attackers)
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . 1 .
. . . 1 1 1 . . .

Parses and creates USI representation of moves.

>>> board = shogi.Board()
>>> shogi.Move(shogi.E2, shogi.E4).usi()
'2e4e'

Parses and creates SFENs

>>> board.sfen()
'lnsgkgsnl/1r5b1/ppppppppp/9/9/9/PPPPPPPPP/1B5R1/LNSGKGSNL b - 1'
>>> board.piece_at(shogi.I5)
Piece.from_symbol('K')

Read KIFs.

>>> import shogi.KIF

>>> kif = shogi.KIF.Parser.parse_file('data/games/habu-fujii-2006.kif')[0]

>>> kif['names'][shogi.BLACK]
'羽生善治'
>>> kif['names'][shogi.WHITE]
'藤井猛'
>>> kif['moves'] # doctest: +ELLIPSIS, +NORMALIZE_WHITESPACE
['7g7f',
 '3c3d',
 ...,
 '9a9b',
 '7a7b+']
>>> kif['win']
'b'

Communicate with a CSA protocol.

Please see random_csa_tcp_match.
Parse professional shogi players' name

>>> import shogi.Person

>>> shogi.Person.Name.is_professional('羽生善治名人・棋聖・王位・王座') True

Performance

python-shogi is not intended to be used by serious shogi engines where performance is critical. The goal is rather to create a simple and relatively highlevel library.

You can install the gmpy2 or gmpy (https://code.google.com/p/gmpy/) modules in order to get a slight performance boost on basic operations like bit scans and population counts.

python-shogi will only ever import very basic general (non-shogi-related) operations from native libraries. All logic is pure Python. There will always be pure Python fallbacks.

Installing

With pip:
```
sudo pip install python-shogi
```

From current source code:

python setup.py sdist
sudo python setup.py install

How to test

> nosetests
or
> python setup.py test # requires python setup.py install

If you want to print lines from the standard output, execute nosetests like following.

> nosetests -s

If you want to test among different Python versions, execute tox.

> pip install tox
> tox

How to release

rm -rf dist
python setup.py sdist
twine upload dist/*

ToDo

Support USI protocol.
Support board.generate_attacks() and use it in board.is_attacked_by() and board.attacker_mask().
Remove rotated bitboards and support Shatranj-style direct lookup like recent python-chess.
Support %MATTA etc. in CSA TCP Protocol.
Support board.is_pinned() and board.pin().

waterwheel31/python-shogi