check-code: allow "grep pattern filename-containing-dash-a" We're trying to forbid "grep -a" and unintentionally complained even if the "-a" was part of the filename. Requiring a space before "-a" to match is probably good enough.

rebase: update working directory when aborting (issue5084)

revset: flatten chained 'list' operations (aka function args) (issue5072) Internal _matchfiles() function can take bunch of arguments, which would lead to a maximum recursion depth error. This patch avoids the excessive stack use by flattening 'list' nodes beforehand. Since getlist() no longer takes a nested 'list' nodes, _parsealiasdecl() also needs to flatten argument list, "aliasname($1, $2, ...)".