Upstream commit:
Date: Mon, 29 Apr 2019 19:13:37 +0500
expand: Fix trailing newlines processing in backquote expanding
According to POSIX.1-2008 we should remove newlines only at the end of
the substitution. Newlines-only substitions causes dash to remove
newlines before beggining of the substitution. The following code:
cat <<END
1
$(echo "")
2
END
prints "1<newline>2" instead of expected "1<newline><newline>2".
This patch fixes trailing newlines processing in backquote expanding.
Signed-off-by: Nikolai Merinov <n.merinov@inango-systems.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Sometimes variable expansions yield empty strings, and if they happen to
be a command someone wants to run like `$foo`, then hush currently
segfaults. So handle `` and $().
Signed-off-by: Mike Frysinger <vapier@gentoo.org>