tests/test-check-rust-format.t

test: use a different timestamp for the updated file

In the test we want to trigger a write after the underlying dirstate changed. To
do so, we need a write. And as we are about to make dirstate update smarter we
need to meddle with the script a bit to make sure there will be a write.

Differential Revision: https://phab.mercurial-scm.org/D11793

#require rustfmt test-repo

  $ . "$TESTDIR/helpers-testrepo.sh"

  $ cd "$TESTDIR"/..
  $ RUSTFMT=$(rustup which --toolchain nightly-2021-11-02 rustfmt)
  $ for f in `testrepohg files 'glob:**/*.rs'` ; do
  >   $RUSTFMT --check --edition=2018 --unstable-features --color=never $f
  > done