tests/test-check-code-hg.t

fncache: move fncache writing to be in a transaction

Previously the fncache was written at lock.release time. This meant it was not
tracked by a transaction, and if an error occurred during the fncache write it
would fail to update the fncache, but would not rollback the transaction,
resulting in an fncache that was not in sync with the files on disk (which
causes verify to fail, and causes streaming clones to not copy all the revlogs).

This uses the new transaction backup mechanism to make the fncache transacted.
It also moves the fncache from being written at lock.release time, to being
written at transaction.close time.

  $ check_code="$TESTDIR"/../contrib/check-code.py
  $ cd "$TESTDIR"/..
  $ if hg identify -q > /dev/null 2>&1; then :
  > else
  >     echo "skipped: not a Mercurial working dir" >&2
  >     exit 80
  > fi

Prepare check for Python files without py extension

  $ cp \
  >   hg \
  >   hgweb.cgi \
  >   contrib/convert-repo \
  >   contrib/dumprevlog \
  >   contrib/hgweb.fcgi \
  >   contrib/hgweb.wsgi \
  >   contrib/simplemerge \
  >   contrib/undumprevlog \
  >   i18n/hggettext \
  >   i18n/posplit \
  >   tests/hghave \
  >   tests/dummyssh \
  >   "$TESTTMP"/
  $ for f in "$TESTTMP"/*; do mv "$f" "$f.py"; done

New errors are not allowed. Warnings are strongly discouraged.
(The writing "no-che?k-code" is for not skipping this file when checking.)

  $ { hg manifest 2>/dev/null; ls "$TESTTMP"/*.py | sed 's-\\-/-g'; } |
  >   xargs "$check_code" --warnings --per-file=0 || false
  Skipping hgext/zeroconf/Zeroconf.py it has no-che?k-code (glob)
  Skipping i18n/polib.py it has no-che?k-code (glob)
  Skipping mercurial/httpclient/__init__.py it has no-che?k-code (glob)
  Skipping mercurial/httpclient/_readers.py it has no-che?k-code (glob)
  Skipping mercurial/httpclient/socketutil.py it has no-che?k-code (glob)