You can run ranger without installing by simply starting the executable
file ranger.py in the top directory of this package.


To install ranger, follow this instructions:

0. Make sure you have a recent version of python, including the
   curses module, which is the case if this shell command prints no errors:
   python -c 'import curses'


1. Copy the file "ranger.py" into any of the directories in the PATH
   environment variable, for example to "/usr/bin/ranger"


2. Copy the directory "ranger" into one of the python module search
   paths, for example to "/usr/lib/python2.6/site-packages/ranger".

   Ensure that the path is listed by the command:
   python -c 'import sys; print("\n".join(sys.path))'


3. Optionally, you can activate an extra feature: When you exit ranger,
   the directory of the current shell can be changed to the last visited
   directory in ranger.  To do so, add this alias to your shell rc file:

   alias rng="source ranger ranger"

   (Unfortunately this feature is shell dependent.  It has been
   successfully tested with BASH only.)

# Chessboard program: you type in moves in algebraic notation, and it'll
# display the position after each move.

# recipes are mu's names for functions
recipe main [
  open-console  # take control of screen, keyboard and mouse

  # The chessboard recipe takes keyboard and screen objects as 'ingredients'.
  #
  # In mu it is good form (though not required) to explicitly show the
  # hardware you rely on.
  #
  # The chessboard also returns the same keyboard and screen objects. In mu it
  # is good form to not modify ingredients of a recipe unless they are also
  # results. Here we clearly modify both keyboard and screen, so we return
  # both.
  #
  # Here the console and screen are both 0, which usually indicates real
  # hardware rather than a fake for testing as you'll see below.
  0:literal/screen, 0:literal/console <- chessboard 0:literal/screen, 0:literal/console

  close-console  # cleanup screen, keyboard and mouse
]

## But enough about mu. Here's what it looks like to run the chessboard program.

scenario print-board-and-read-move [
  $close-trace  # administrivia: most scenarios save and check traces, but this one gets too large/slow
  # we'll make the screen really wide because the program currently prints out a long line
  assume-screen 120:literal/width, 20:literal/height
  # initialize keyboard to type in a move
  assume-console [
    type [a2-a4
]
  ]
  run [
    screen:address, console:address <- chessboard screen:address, console:address
#?     $browse-trace #? 1
#?     $close-trace #? 1
    # icon for the cursor
    screen:address <- print-character screen:address, 9251:literal  # '␣'
  ]
  screen-should-contain [
  #            1         2         3         4         5         6         7         8         9         10        11
  #  012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789
    .Stupid text-mode chessboard. White pieces in uppercase; black pieces in lowercase. No checking for legal moves.         .
    .                                                                                                                        .
    .8 | r n b q k b n r                                                                                                     .
    .7 | p p p p p p p p                                                                                                     .
    .6 |                                                                                                                     .
    .5 |                                                                                                                     .
    .4 | P                                                                                                                   .
    .3 |                                                                                                                     .
    .2 |   P P P P P P P                                                                                                     .
    .1 | R N B Q K B N R                                                                                                     .
    .  +----------------                                                                                                     .
    .    a b c d e f g h                                                                                                     .
    .                                                                                                                        .
    .Type in your move as <from square>-<to square>. For example: 'a2-a4'. Then press <enter>.                               .
    .                                                                                                                        .
    .Hit 'q' to exit.                                                                                                        .
    .                                                                                                                        .
    .move: ␣                                                                                                                 .
    .                                                                                                                        .
    .                                                                                                                        .
  ]
]

#? scenario foo [ #? 1
#?   $print [aaa] #? 1
#?   run [ #? 1
#?     1:number <- copy 34:literal #? 1
#?   ] #? 1
#?   memory-should-contain [ #? 1
#?     1 <- 34 #? 1
#?   ] #? 1
#?   $print [zzz] #? 1
#? ] #? 1

## Here's how 'chessboard' is implemented.

recipe chessboard [
#?   $start-tracing [schedule] #? 2
#?   $start-tracing #? 1
  new-default-space
  screen:address <- next-ingredient
  console:address <- next-ingredient
#?   $print [screen: ], screen:address, [, console: ], console:address, [ 
#? ] #? 1
  board:address:array:address:array:character <- initial-position
  # hook up stdin
  stdin:address:channel <- new-channel 10:literal/capacity
  start-running send-keys-to-channel:recipe, console:address, stdin:address:channel, screen:address
  # buffer lines in stdin
  buffered-stdin:address:channel <- new-channel 10:literal/capacity
  start-running buffer-lines:recipe, stdin:address:channel, buffered-stdin:address:channel
  {
    msg:address:array:character <- new [Stupid text-mode chessboard. White pieces in uppercase; black pieces in lowercase. No checking for legal moves.
]
    print-string screen:address, msg:address:array:character
#?     $print [aaa
#? ] #? 1
    cursor-to-next-line screen:address
    print-board screen:address, board:address:array:address:array:character
    cursor-to-next-line screen:address
    msg:address:array:character <- new [Type in your move as <from square>-<to square>. For example: 'a2-a4'. Then press <enter>.
]
    print-string screen:address, msg:address:array:character
#?     $print [bbb
#? ] #? 1
    cursor-to-next-line screen:address
    msg:address:array:character <- new [Hit 'q' to exit.
]
    print-string screen:address, msg:address:array:character
#?     $print [ccc
#? ] #? 1
    {
      cursor-to-next-line screen:address
      msg:address:array:character <- new [move: ]
      print-string screen:address, msg:address:array:character
#?     $print [ddd
#? ] #? 1
      m:address:move, quit:boolean, error:boolean <- read-move buffered-stdin:address:channel, screen:address
#?     $print [eee
#? ] #? 1
      break-if quit:boolean, +quit:offset
      buffered-stdin:address:channel <- clear-channel buffered-stdin:address:channel  # cleanup after error. todo: test this?
      loop-if error:boolean
    }
    board:address:array:address:array:character <- make-move board:address:array:address:array:character, m:address:move
    clear-screen screen:address
    loop
  }
  +quit
#?   $print [aaa] #? 1
]

## a board is an array of files, a file is an array of characters (squares)

recipe new-board [
  new-default-space
  initial-position:address:array:number <- next-ingredient
  # assert(length(initial-position) == 64)
  len:number <- length initial-position:address:array:number/deref
  correct-length?:boolean <- equal len:number, 64:literal
  assert correct-length?:boolean, [chessboard had incorrect size]
  # board is an array of pointers to files; file is an array of characters
  board:address:array:address:array:character <- new location:type, 8:literal
  col:number <- copy 0:literal
  {
    done?:boolean <- equal col:number, 8:literal
    break-if done?:boolean
    file:address:address:array:character <- index-address board:address:array:address:array:character/deref, col:number
    file:address:address:array:character/deref <- new-file initial-position:address:array:number, col:number
    col:number <- add col:number, 1:literal
    loop
  }
  reply board:address:array:address:array:character
]

recipe new-file [
  new-default-space
  position:address:array:number <- next-ingredient
  index:number <- next-ingredient
  index:number <- multiply index:number, 8:literal
  result:address:array:character <- new character:type, 8:literal
  row:number <- copy 0:literal
  {
    done?:boolean <- equal row:number, 8:literal
    break-if done?:boolean
    dest:address:character <- index-address result:address:array:character/deref, row:number
    dest:address:character/deref <- index position:address:array:number/deref, index:number
    row:number <- add row:number, 1:literal
    index:number <- add index:number, 1:literal
    loop
  }
  reply result:address:array:character
]

recipe print-board [
  new-default-space
  screen:address <- next-ingredient
  board:address:array:address:array:character <- next-ingredient
  row:number <- copy 7:literal  # start printing from the top of the board
  # print each row
#?   $print [printing board to screen ], screen:address, [ 
#? ] #? 1
  {
    done?:boolean <- lesser-than row:number, 0:literal
    break-if done?:boolean
#?     $print [printing rank ], row:number, [ 
#? ] #? 1
    # print rank number as a legend
    rank:number <- add row:number, 1:literal
    print-integer screen:address, rank:number
    s:address:array:character <- new [ | ]
    print-string screen:address, s:address:array:character
    # print each square in the row
    col:number <- copy 0:literal
    {
      done?:boolean <- equal col:number, 8:literal
      break-if done?:boolean
      f:address:array:character <- index board:address:array:address:array:character/deref, col:number
      c:character <- index f:address:array:character/deref, row:number
      print-character screen:address, c:character
      print-character screen:address, 32:literal  # ' '
      col:number <- add col:number, 1:literal
      loop
    }
    row:number <- subtract row:number, 1:literal
    cursor-to-next-line screen:address
    loop
  }
  # print file letters as legend
#?   $print [printing legend
#? ] #? 1
  s:address:array:character <- new [  +----------------]
  print-string screen:address, s:address:array:character
  screen:address <- cursor-to-next-line screen:address
#?   screen:address <- print-character screen:address, 97:literal #? 1
  s:address:array:character <- new [    a b c d e f g h]
  screen:address <- print-string screen:address, s:address:array:character
  screen:address <- cursor-to-next-line screen:address
#?   $print [done printing board
#? ] #? 1
]

# board:address:array:address:array:character <- initial-position
recipe initial-position [
  new-default-space
  # layout in memory (in raster order):
  #   R P _ _ _ _ p r
  #   N P _ _ _ _ p n
  #   B P _ _ _ _ p b
  #   Q P _ _ _ _ p q
  #   K P _ _ _ _ p k
  #   B P _ _ _ _ p B
  #   N P _ _ _ _ p n
  #   R P _ _ _ _ p r
  initial-position:address:array:number <- new-array 82:literal/R, 80:literal/P, 32:literal/blank, 32:literal/blank, 32:literal/blank, 32:literal/blank, 112:literal/p, 114:literal/r, 78:literal/N, 80:literal/P, 32:literal/blank, 32:literal/blank, 32:literal/blank, 32:literal/blank, 112:literal/p, 110:literal/n, 66:literal/B, 80:literal/P, 32:literal/blank, 32:literal/blank, 32:literal/blank, 32:literal/blank, 112:literal/p, 98:literal/b, 81:literal/Q, 80:literal/P, 32:literal/blank, 32:literal/blank, 32:literal/blank, 32:literal/blank, 112:literal/p, 113:literal/q, 75:literal/K, 80:literal/P, 32:literal/blank, 32:literal/blank, 32:literal/blank, 32:literal/blank, 112:literal/p, 107:literal/k, 66:literal/B, 80:literal/P, 32:literal/blank, 32:literal/blank, 32:literal/blank, 32:literal/blank, 112:literal/p, 98:literal/b, 78:literal/N, 80:literal/P, 32:literal/blank, 32:literal/blank, 32:literal/blank, 32:literal/blank, 112:literal/p, 110:literal/n, 82:literal/R, 80:literal/P, 32:literal/blank, 32:literal/blank, 32:literal/blank, 32:literal/blank, 112:literal/p, 114:literal/r
#?       82:literal/R, 80:literal/P, 32:literal/blank, 32:literal/blank, 32:literal/blank, 32:literal/blank, 112:literal/p, 114:literal/r,
#?       78:literal/N, 80:literal/P, 32:literal/blank, 32:literal/blank, 32:literal/blank, 32:literal/blank, 112:literal/p, 110:literal/n,
#?       66:literal/B, 80:literal/P, 32:literal/blank, 32:literal/blank, 32:literal/blank, 32:literal/blank, 112:literal/p, 98:literal/b, 
#?       81:literal/Q, 80:literal/P, 32:literal/blank, 32:literal/blank, 32:literal/blank, 32:literal/blank, 112:literal/p, 113:literal/q,
#?       75:literal/K, 80:literal/P, 32:literal/blank, 32:literal/blank, 32:literal/blank, 32:literal/blank, 112:literal/p, 107:literal/k,
#?       66:literal/B, 80:literal/P, 32:literal/blank, 32:literal/blank, 32:literal/blank, 32:literal/blank, 112:literal/p, 98:literal/b,
#?       78:literal/N, 80:literal/P, 32:literal/blank, 32:literal/blank, 32:literal/blank, 32:literal/blank, 112:literal/p, 110:literal/n,
#?       82:literal/R, 80:literal/P, 32:literal/blank, 32:literal/blank, 32:literal/blank, 32:literal/blank, 112:literal/p, 114:literal/r
  board:address:array:address:array:character <- new-board initial-position:address:array:number
  reply board:address:array:address:array:character
]

scenario printing-the-board [
  assume-screen 30:literal/width, 12:literal/height
  run [
    1:address:array:address:array:character/board <- initial-position
    screen:address <- print-board screen:address, 1:address:array:address:array:character/board
#?     $dump-screen #? 1
  ]
  screen-should-contain [
  #  012345678901234567890123456789
    .8 | r n b q k b n r           .
    .7 | p p p p p p p p           .
    .6 |                           .
    .5 |                           .
    .4 |                           .
    .3 |                           .
    .2 | P P P P P P P P           .
    .1 | R N B Q K B N R           .
    .  +----------------           .
    .    a b c d e f g h           .
    .                              .
    .                              .
  ]
]

## data structure: move

container move [
  # valid range: 0-7
  from-file:number
  from-rank:number
  to-file:number
  to-rank:number
]

# result:address:move, quit?:boolean, error?:boolean <- read-move stdin:address:channel, screen:address
# prints only error messages to screen
recipe read-move [
  new-default-space
  stdin:address:channel <- next-ingredient
  screen:address <- next-ingredient
#?   $print screen:address #? 1
  from-file:number, quit?:boolean, error?:boolean <- read-file stdin:address:channel, screen:address
  reply-if quit?:boolean, 0:literal/dummy, quit?:boolean, error?:boolean
  reply-if error?:boolean, 0:literal/dummy, quit?:boolean, error?:boolean
#?   close-console #? 1
  # construct the move object
  result:address:move <- new move:type
  x:address:number <- get-address result:address:move/deref, from-file:offset
  x:address:number/deref <- copy from-file:number
  x:address:number <- get-address result:address:move/deref, from-rank:offset
  x:address:number/deref, quit?:boolean, error?:boolean <- read-rank stdin:address:channel, screen:address
  reply-if quit?:boolean, 0:literal/dummy, quit?:boolean, error?:boolean
  reply-if error?:boolean, 0:literal/dummy, quit?:boolean, error?:boolean
  error?:boolean <- expect-from-channel stdin:address:channel, 45:literal/dash, screen:address
  reply-if error?:boolean, 0:literal/dummy, 0:literal/quit, error?:boolean
  x:address:number <- get-address result:address:move/deref, to-file:offset
  x:address:number/deref, quit?:boolean, error?:boolean <- read-file stdin:address:channel, screen:address
  reply-if quit?:boolean, 0:literal/dummy, quit?:boolean, error?:boolean
  reply-if error?:boolean, 0:literal/dummy, quit?:boolean, error?:boolean
  x:address:number <- get-address result:address:move/deref, to-rank:offset
  x:address:number/deref, quit?:boolean, error?:boolean <- read-rank stdin:address:channel, screen:address
  reply-if quit?:boolean, 0:literal/dummy, quit?:boolean, error?:boolean
  reply-if error?:boolean, 0:literal/dummy, quit?:boolean, error?:boolean
#?   $exit #? 1
  error?:boolean <- expect-from-channel stdin:address:channel, 10:literal/newline, screen:address
  reply-if error?:boolean, 0:literal/dummy, 0:literal/quit, error?:boolean
  reply result:address:move, quit?:boolean, error?:boolean
]

# file:number, quit:boolean, error:boolean <- read-file stdin:address:channel, screen:address
# valid values for file: 0-7
recipe read-file [
  new-default-space
  stdin:address:channel <- next-ingredient
  screen:address <- next-ingredient
  c:character, stdin:address:channel <- read stdin:address:channel
  {
    q-pressed?:boolean <- equal c:character, 81:literal  # 'Q'
    break-unless q-pressed?:boolean
    reply 0:literal/dummy, 1:literal/quit, 0:literal/error
  }
  {
    q-pressed?:boolean <- equal c:character, 113:literal  # 'q'
    break-unless q-pressed?:boolean
    reply 0:literal/dummy, 1:literal/quit, 0:literal/error
  }
  {
    empty-fake-keyboard?:boolean <- equal c:character, 0:literal/eof
    break-unless empty-fake-keyboard?:boolean
    reply 0:literal/dummy, 1:literal/quit, 0:literal/error
  }
  {
    newline?:boolean <- equal c:character, 10:literal/newline
    break-unless newline?:boolean
    error-message:address:array:character <- new [that's not enough]
    print-string screen:address, error-message:address:array:character
    reply 0:literal/dummy, 0:literal/quit, 1:literal/error
  }
  file:number <- subtract c:character, 97:literal  # 'a'
#?   $print file:number, [ 
#? ] #? 1
  # 'a' <= file <= 'h'
  {
    above-min:boolean <- greater-or-equal file:number, 0:literal
    break-if above-min:boolean
    error-message:address:array:character <- new [file too low: ]
    print-string screen:address, error-message:address:array:character
    print-character screen:address, c:character
    cursor-to-next-line screen:address
    reply 0:literal/dummy, 0:literal/quit, 1:literal/error
  }
  {
    below-max:boolean <- lesser-than file:number, 8:literal
    break-if below-max:boolean
    error-message:address:array:character <- new [file too high: ]
    print-string screen:address, error-message:address:array:character
    print-character screen:address, c:character
    reply 0:literal/dummy, 0:literal/quit, 1:literal/error
  }
  reply file:number, 0:literal/quit, 0:literal/error
]

# rank:number <- read-rank stdin:address:channel, screen:address
# valid values: 0-7, -1 (quit), -2 (error)
recipe read-rank [
  new-default-space
  stdin:address:channel <- next-ingredient
  screen:address <- next-ingredient
  c:character, stdin:address:channel <- read stdin:address:channel
  {
    q-pressed?:boolean <- equal c:character, 81:literal  # 'Q'
    break-unless q-pressed?:boolean
    reply 0:literal/dummy, 1:literal/quit, 0:literal/error
  }
  {
    q-pressed?:boolean <- equal c:character, 113:literal  # 'q'
    break-unless q-pressed?:boolean
    reply 0:literal/dummy, 1:literal/quit, 0:literal/error
  }
  {
    newline?:boolean <- equal c:character, 10:literal  # newline
    break-unless newline?:boolean
    error-message:address:array:character <- new [that's not enough]
    print-string screen:address, error-message:address:array:character
    reply 0:literal/dummy, 0:literal/quit, 1:literal/error
  }
  rank:number <- subtract c:character, 49:literal  # '1'
#?   $print rank:number, [ 
#? ] #? 1
  # assert'1' <= rank <= '8'
  {
    above-min:boolean <- greater-or-equal rank:number, 0:literal
    break-if above-min:boolean
    error-message:address:array:character <- new [rank too low: ]
    print-string screen:address, error-message:address:array:character
    print-character screen:address, c:character
    reply 0:literal/dummy, 0:literal/quit, 1:literal/error
  }
  {
    below-max:boolean <- lesser-or-equal rank:number, 7:literal
    break-if below-max:boolean
    error-message:address:array:character <- new [rank too high: ]
    print-string screen:address, error-message:address:array:character
    print-character screen:address, c:character
    reply 0:literal/dummy, 0:literal/quit, 1:literal/error
  }
  reply rank:number, 0:literal/quit, 0:literal/error
]

# read a character from the given channel and check that it's what we expect
# return true on error
recipe expect-from-channel [
  new-default-space
  stdin:address:channel <- next-ingredient
  expected:character <- next-ingredient
  screen:address <- next-ingredient
  c:character, stdin:address:channel <- read stdin:address:channel
  match?:boolean <- equal c:character, expected:character
  {
    break-if match?:boolean
    s:address:array:character <- new [expected character not found]
    print-string screen:address, s:address:array:character
  }
  result:boolean <- not match?:boolean
  reply result:boolean
]

scenario read-move-blocking [
  assume-screen 20:literal/width, 2:literal/height
  run [
#?     $start-tracing #? 1
    1:address:channel <- new-channel 2:literal
#?     $print [aaa channel address: ], 1:address:channel, [ 
#? ] #? 1
    2:number/routine <- start-running read-move:recipe, 1:address:channel, screen:address
    # 'read-move' is waiting for input
    wait-for-routine 2:number
#?     $print [bbb channel address: ], 1:address:channel, [ 
#? ] #? 1
    3:number <- routine-state 2:number/id
#?     $print [I: routine ], 2:number, [ state ], 3:number [ 
#? ] #? 1
    4:boolean/waiting? <- equal 3:number/routine-state, 2:literal/waiting
    assert 4:boolean/waiting?, [
F read-move-blocking: routine failed to pause after coming up (before any keys were pressed)]
    # press 'a'
#?     $print [ccc channel address: ], 1:address:channel, [ 
#? ] #? 1
#?     $exit #? 1
    1:address:channel <- write 1:address:channel, 97:literal  # 'a'
    restart 2:number/routine
    # 'read-move' still waiting for input
    wait-for-routine 2:number
    3:number <- routine-state 2:number/id
#?     $print [II: routine ], 2:number, [ state ], 3:number [ 
#? ] #? 1
    4:boolean/waiting? <- equal 3:number/routine-state, 2:literal/waiting
    assert 4:boolean/waiting?, [
F read-move-blocking: routine failed to pause after rank 'a']
    # press '2'
    1:address:channel <- write 1:address:channel, 50:literal  # '2'
    restart 2:number/routine
    # 'read-move' still waiting for input
    wait-for-routine 2:number
    3:number <- routine-state 2:number/id
#?     $print [III: routine ], 2:number, [ state ], 3:number [ 
#? ] #? 1
    4:boolean/waiting? <- equal 3:number/routine-state, 2:literal/waiting
    assert 4:boolean/waiting?, [
F read-move-blocking: routine failed to pause after file 'a2']
    # press '-'
    1:address:channel <- write 1:address:channel, 45:literal  # '-'
    restart 2:number/routine
    # 'read-move' still waiting for input
    wait-for-routine 2:number
    3:number <- routine-state 2:number
#?     $print [IV: routine ], 2:number, [ state ], 3:number [ 
#? ] #? 1
    4:boolean/waiting? <- equal 3:number/routine-state, 2:literal/waiting
    assert 4:boolean/waiting?/routine-state, [
F read-move-blocking: routine failed to pause after hyphen 'a2-']
    # press 'a'
    1:address:channel <- write 1:address:channel, 97:literal  # 'a'
    restart 2:number/routine
    # 'read-move' still waiting for input
    wait-for-routine 2:number
    3:number <- routine-state 2:number
#?     $print [V: routine ], 2:number, [ state ], 3:number [ 
#? ] #? 1
    4:boolean/waiting? <- equal 3:number/routine-state, 2:literal/waiting
    assert 4:boolean/waiting?/routine-state, [
F read-move-blocking: routine failed to pause after rank 'a2-a']
    # press '4'
    1:address:channel <- write 1:address:channel, 52:literal  # '4'
    restart 2:number/routine
    # 'read-move' still waiting for input
    wait-for-routine 2:number
    3:number <- routine-state 2:number
#?     $print [VI: routine ], 2:number, [ state ], 3:number [ 
#? ] #? 1
    4:boolean/waiting? <- equal 3:number/routine-state, 2:literal/waiting
    assert 4:boolean/waiting?, [
F read-move-blocking: routine failed to pause after file 'a2-a4']
    # press 'newline'
    1:address:channel <- write 1:address:channel, 10:literal  # newline
    restart 2:number/routine
    # 'read-move' now completes
    wait-for-routine 2:number
    3:number <- routine-state 2:number
#?     $print [VII: routine ], 2:number, [ state ], 3:number [ 
#? ] #? 1
    4:boolean/completed? <- equal 3:number/routine-state, 1:literal/completed
    assert 4:boolean/completed?, [
F read-move-blocking: routine failed to terminate on newline]
    trace [test], [reached end]
  ]
  trace-should-contain [
    test: reached end
  ]
]

scenario read-move-quit [
  assume-screen 20:literal/width, 2:literal/height
  run [
    1:address:channel <- new-channel 2:literal
    2:number/routine <- start-running read-move:recipe, 1:address:channel, screen:address
    # 'read-move' is waiting for input
    wait-for-routine 2:number
    3:number <- routine-state 2:number/id
    4:boolean/waiting? <- equal 3:number/routine-state, 2:literal/waiting
    assert 4:boolean/waiting?, [
F read-move-quit: routine failed to pause after coming up (before any keys were pressed)]
    # press 'q'
    1:address:channel <- write 1:address:channel, 113:literal  # 'q'
    restart 2:number/routine
    # 'read-move' completes
    wait-for-routine 2:number
    3:number <- routine-state 2:number/id
    4:boolean/completed? <- equal 3:number/routine-state, 1:literal/completed
    assert 4:boolean/completed?, [
F read-move-quit: routine failed to terminate on 'q']
    trace [test], [reached end]
  ]
  trace-should-contain [
    test: reached end
  ]
]

scenario read-move-illegal-file [
  assume-screen 20:literal/width, 2:literal/height
  run [
    1:address:channel <- new-channel 2:literal
    2:number/routine <- start-running read-move:recipe, 1:address:channel, screen:address
    # 'read-move' is waiting for input
    wait-for-routine 2:number
    3:number <- routine-state 2:number/id
    4:boolean/waiting? <- equal 3:number/routine-state, 2:literal/waiting
    assert 4:boolean/waiting?, [
F read-move-file: routine failed to pause after coming up (before any keys were pressed)]
    1:address:channel <- write 1:address:channel, 50:literal  # '2'
    restart 2:number/routine
    wait-for-routine 2:number
  ]
  screen-should-contain [
    .file too low: 2     .
    .                    .
  ]
]

scenario read-move-illegal-rank [
  assume-screen 20:literal/width, 2:literal/height
  run [
    1:address:channel <- new-channel 2:literal
    2:number/routine <- start-running read-move:recipe, 1:address:channel, screen:address
    # 'read-move' is waiting for input
    wait-for-routine 2:number
    3:number <- routine-state 2:number/id
    4:boolean/waiting? <- equal 3:number/routine-state, 2:literal/waiting
    assert 4:boolean/waiting?, [
F read-move-file: routine failed to pause after coming up (before any keys were pressed)]
    1:address:channel <- write 1:address:channel, 97:literal  # 'a'
    1:address:channel <- write 1:address:channel, 97:literal  # 'a'
    restart 2:number/routine
    wait-for-routine 2:number
  ]
  screen-should-contain [
    .rank too high: a    .
    .                    .
  ]
]

scenario read-move-empty [
  assume-screen 20:literal/width, 2:literal/height
  run [
    1:address:channel <- new-channel 2:literal
    2:number/routine <- start-running read-move:recipe, 1:address:channel, screen:address
    # 'read-move' is waiting for input
    wait-for-routine 2:number
    3:number <- routine-state 2:number/id
    4:boolean/waiting? <- equal 3:number/routine-state, 2:literal/waiting
    assert 4:boolean/waiting?, [
F read-move-file: routine failed to pause after coming up (before any keys were pressed)]
    1:address:channel <- write 1:address:channel, 10:literal/newline
    1:address:channel <- write 1:address:channel, 97:literal  # 'a'
    restart 2:number/routine
    wait-for-routine 2:number
  ]
  screen-should-contain [
    .that's not enough   .
    .                    .
  ]
]

recipe make-move [
  new-default-space
  b:address:array:address:array:character <- next-ingredient
  m:address:move <- next-ingredient
  from-file:number <- get m:address:move/deref, from-file:offset
#?   $print from-file:number, [ 
#? ] #? 1
  from-rank:number <- get m:address:move/deref, from-rank:offset
#?   $print from-rank:number, [ 
#? ] #? 1
  to-file:number <- get m:address:move/deref, to-file:offset
#?   $print to-file:number, [ 
#? ] #? 1
  to-rank:number <- get m:address:move/deref, to-rank:offset
#?   $print to-rank:number, [ 
#? ] #? 1
  f:address:array:character <- index b:address:array:address:array:character/deref, from-file:number
  src:address:character/square <- index-address f:address:array:character/deref, from-rank:number
  f:address:array:character <- index b:address:array:address:array:character/deref, to-file:number
  dest:address:character/square <- index-address f:address:array:character/deref, to-rank:number
#?   $print src:address:character/deref, [ 
#? ] #? 1
  dest:address:character/deref/square <- copy src:address:character/deref/square
  src:address:character/deref/square <- copy 32:literal  # ' '
  reply b:address:array:address:array:character/same-as-ingredient:0
]

scenario making-a-move [
  assume-screen 30:literal/width, 12:literal/height
  run [
    2:address:array:address:array:character/board <- initial-position
    3:address:move <- new move:type
    4:address:number <- get-address 3:address:move/deref, from-file:offset
    4:address:number/deref <- copy 6:literal/g
    5:address:number <- get-address 3:address:move/deref, from-rank:offset
    5:address:number/deref <- copy 1:literal/2
    6:address:number <- get-address 3:address:move/deref, to-file:offset
    6:address:number/deref <- copy 6:literal/g
    7:address:number <- get-address 3:address:move/deref, to-rank:offset
    7:address:number/deref <- copy 3:literal/4
    2:address:array:address:array:character/board <- make-move 2:address:array:address:array:character/board, 3:address:move
    screen:address <- print-board screen:address, 2:address:array:address:array:character/board
  ]
  screen-should-contain [
  #  012345678901234567890123456789
    .8 | r n b q k b n r           .
    .7 | p p p p p p p p           .
    .6 |                           .
    .5 |                           .
    .4 |             P             .
    .3 |                           .
    .2 | P P P P P P   P           .
    .1 | R N B Q K B N R           .
    .  +----------------           .
    .    a b c d e f g h           .
    .                              .
  ]
]