tests/test-requires.t

tests: stabilize `test-clonebundles-autogen.t` on Windows

The problem was that the commands are spun up with `shell=True`, which uses
`cmd.exe`, which doesn't understand `$foo` style variables.  The HGCB variable
expansion has to be delayed, because it's figured out right before launching
the command.  We could probably add a conditional for Windows, and rewrite the
config to use `%foo%` style variables, but it's more maintainable to just wrap
the command in a bash shell invocation.

The forward style slashes in the path are needed to avoid accruing double
backslashes (when switching between shells- the url template seems fine).  Also
need to strong quote the command so that the double quotes don't get stripped
off of `$HGCB_BUNDLE_PATH`, which results in:

    sh: 1: Syntax error: Unterminated quoted string
    abort: command returned status 2: sh -c "cp $HGCB_BUNDLE_PATH $TESTTMP/final-upload/"

  $ hg init t
  $ cd t
  $ echo a > a
  $ hg add a
  $ hg commit -m test
  $ rm .hg/requires
  $ hg tip
  abort: unknown version (65535) in revlog 00changelog
  [50]
  $ echo indoor-pool > .hg/requires
  $ hg tip
  abort: repository requires features unknown to this Mercurial: indoor-pool
  (see https://mercurial-scm.org/wiki/MissingRequirement for more information)
  [255]
  $ echo outdoor-pool >> .hg/requires
  $ hg tip
  abort: repository requires features unknown to this Mercurial: indoor-pool outdoor-pool
  (see https://mercurial-scm.org/wiki/MissingRequirement for more information)
  [255]
  $ cd ..

Test checking between features supported locally and ones required in
another repository of push/pull/clone on localhost:

  $ mkdir supported-locally
  $ cd supported-locally

  $ hg init supported
  $ echo a > supported/a
  $ hg -R supported commit -Am '#0 at supported'
  adding a

  $ echo 'featuresetup-test' >> supported/.hg/requires
  $ cat > $TESTTMP/supported-locally/supportlocally.py <<EOF
  > from mercurial import extensions, localrepo
  > def featuresetup(ui, supported):
  >     for name, module in extensions.extensions(ui):
  >         if __name__ == module.__name__:
  >             # support specific feature locally
  >             supported |= {b'featuresetup-test'}
  >             return
  > def uisetup(ui):
  >     localrepo.featuresetupfuncs.add(featuresetup)
  > EOF
  $ cat > supported/.hg/hgrc <<EOF
  > [extensions]
  > # enable extension locally
  > supportlocally = $TESTTMP/supported-locally/supportlocally.py
  > EOF
  $ hg -R supported debugrequirements
  dotencode
  dirstate-v2 (dirstate-v2 !)
  featuresetup-test
  fncache
  generaldelta
  persistent-nodemap (rust !)
  revlog-compression-zstd (zstd !)
  revlogv1
  share-safe
  sparserevlog
  store
  $ hg -R supported status

  $ hg init push-dst
  $ hg -R supported push push-dst
  pushing to push-dst
  abort: required features are not supported in the destination: featuresetup-test
  [255]

  $ hg init pull-src
  $ hg -R pull-src pull supported
  pulling from supported
  abort: required features are not supported in the destination: featuresetup-test
  [255]

  $ hg clone supported clone-dst
  abort: repository requires features unknown to this Mercurial: featuresetup-test
  (see https://mercurial-scm.org/wiki/MissingRequirement for more information)
  [255]
  $ hg clone --pull supported clone-dst
  abort: required features are not supported in the destination: featuresetup-test
  [255]

Bundlerepo also enforces the underlying repo requirements

  $ hg --cwd supported bundle --all ../bundle.hg
  1 changesets found
  $ echo outdoor-pool > push-dst/.hg/requires
  $ hg --cwd push-dst log -R ../bundle.hg -T phases
  abort: repository requires features unknown to this Mercurial: outdoor-pool
  (see https://mercurial-scm.org/wiki/MissingRequirement for more information)
  [255]

  $ cd ..