tests/test-casecollision.t

sparse: refactor sparsechecksum()

This was relying on garbage collection to close the opened
file, which is a bug. Both callers simply called into self.vfs
to resolve the path. So refactor to use the vfs layer.

While we're here, rename the method to reflect it is internal
and to break anyone relying on the old behavior.

#require no-icasefs

test file addition with colliding case

  $ hg init repo1
  $ cd repo1
  $ echo a > a
  $ echo A > A
  $ hg add a
  $ hg st
  A a
  ? A
  $ hg add --config ui.portablefilenames=abort A
  abort: possible case-folding collision for A
  [255]
  $ hg st
  A a
  ? A
  $ hg add A
  warning: possible case-folding collision for A
  $ hg st
  A A
  A a
  $ hg forget A
  $ hg st
  A a
  ? A
  $ hg add --config ui.portablefilenames=no A
  $ hg st
  A A
  A a
  $ mkdir b
  $ touch b/c b/D
  $ hg add b
  adding b/D
  adding b/c
  $ touch b/d b/C
  $ hg add b/C
  warning: possible case-folding collision for b/C
  $ hg add b/d
  warning: possible case-folding collision for b/d
  $ touch b/a1 b/a2
  $ hg add b
  adding b/a1
  adding b/a2
  $ touch b/A2 b/a1.1
  $ hg add b/a1.1 b/A2
  warning: possible case-folding collision for b/A2
  $ touch b/f b/F
  $ hg add b/f b/F
  warning: possible case-folding collision for b/f
  $ touch g G
  $ hg add g G
  warning: possible case-folding collision for g
  $ mkdir h H
  $ touch h/x H/x
  $ hg add h/x H/x
  warning: possible case-folding collision for h/x
  $ touch h/s H/s
  $ hg add h/s
  $ hg add H/s
  warning: possible case-folding collision for H/s

case changing rename must not warn or abort

  $ echo c > c
  $ hg ci -qAmx
  $ hg mv c C
  $ cd ..