comparison mercurial/help/config.txt @ 22158:bc2132dfc0a4

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.

22157:bd45d92883f9

repository in the same manner as the purge extension.

Positional arguments like ``$1``, ``$2``, etc. in the alias definition
expand to the command arguments. Unmatched arguments are
removed. ``$0`` expands to the alias name and ``$@`` expands to all
arguments separated by a space. These expansions happen before the
command is passed to the shell.

Shell aliases are executed in an environment where ``$HG`` expands to
the path of the Mercurial that was used to execute the alias. This is
useful when you want to call further Mercurial commands in a shell
alias, as was done above for the purge alias. In addition,

22158:bc2132dfc0a4

repository in the same manner as the purge extension.

Positional arguments like ``$1``, ``$2``, etc. in the alias definition
expand to the command arguments. Unmatched arguments are
removed. ``$0`` expands to the alias name and ``$@`` expands to all
arguments separated by a space. ``"$@"`` (with quotes) expands to all
arguments quoted individually and separated by a space. These expansions
happen before the command is passed to the shell.

Shell aliases are executed in an environment where ``$HG`` expands to
the path of the Mercurial that was used to execute the alias. This is
useful when you want to call further Mercurial commands in a shell
alias, as was done above for the purge alias. In addition,