alias: expand "$@" as list of parameters quoted individually (BC) (
issue4200)
Before this patch, there was no way to pass in all the positional parameters as
separate words down to another command.
(1) $@ (without quotes) would expand to all the parameters separated by a space.
This would work fine for arguments without spaces, but arguments with spaces
in them would be split up by POSIX shells into separate words.
(2) '$@' (in single quotes) would expand to all the parameters within a pair of
single quotes. POSIX shells would then treat the entire list of arguments
as one word.
(3) "$@" (in double quotes) would expand similarly to (2).
With this patch, we expand "$@" (in double quotes) as all positional
parameters, quoted individually with util.shellquote, and separated by spaces.
Under standard field-splitting conditions, POSIX shells will tokenize each
argument into exactly one word.
This is a backwards-incompatible change, but the old behavior was arguably a
bug: Bourne-derived shells have expanded "$@" as a tokenized list of positional
parameters for a very long time. I could find this behavior specified in IEEE
Std 1003.1-2001, and this probably goes back to much further before that.