$ hg init

  $ echo 0 > a

  $ echo 0 > b

  $ hg ci -A -m m

  adding a

  adding b

  $ hg rm a

  $ hg cat a

  0

  $ hg cat --decode a # more tests in test-encode

  0

  $ echo 1 > b

  $ hg ci -m m

  $ echo 2 > b

  $ hg cat -r 0 a

  0

  $ hg cat -r 0 b

  0

  $ hg cat -r 1 a

  a: no such file in rev 7040230c159c

  [1]

  $ hg cat -r 1 b

  1