Git alias syntax help

["Σταύρος Ντέντος" <stdedos@gmail.com>]

Hello there,

I am having an issue with git-aliases - specifically, the intricacies
involved in their syntax.

In general, the syntax is confusing to me, especially when it is
_wise_ to use quotes inside a `!sh` alias.
e.g. which one would be the correct one
new = "!f() { : git log ; git log \"${1}@{1}..${1}@{0}\" \"$@\" ; } ; f"
new = !f() { : git log ; git log "${1}@{1}..${1}@{0}" "$@" ; } ; f

(from converting this:
https://git.wiki.kernel.org/index.php/Aliases#What.27s_new.3F)
        new = !sh -c 'git log $1@{1}..$1@{0} "$@"'

The alias confusing me is more specifically this:
https://git.wiki.kernel.org/index.php/Aliases#simple_diff_ignoring_line_number_changes

diffsort = !sh -c 'git diff "$@" | grep "^[+-]" | sort --key=1.2 | uniq -u -s1'

The output of:
$  colordiff -su <(git diffsort HEAD^..HEAD) <(git diffsort HEAD^^..HEAD^)
Files /dev/fd/63 and /dev/fd/62 are identical
is a little unexpected, since I know for a fact that one of the
referced commits is not a code block moved.

(and indeed, if I do it myself:
$ colordiff -su <(git diff HEAD^..HEAD | grep "^[+-]" | sort --key=1.2
| uniq -u -s1) <(git diff HEAD^^..HEAD^ | grep "^[+-]" | sort
--key=1.2 | uniq -u -s1)
--- /dev/fd/63 2020-01-14 17:17:45.103771745 +0200
+++ /dev/fd/62 2020-01-14 17:17:45.103771745 +0200
@@ -1,2 +1,13 @@
[....]

it works.

The issue I have found is: $@ is not expanded

Tested with:

diffsort = !sh -c 'echo "+git diff $@" | grep "^[+-]" | sort --key=1.2
| uniq -u -s1'
$ git diffsort HEAD^..HEAD
+git diff

I would appreciate if someone would clear out the air for me.
I think I have done my homework enough, and it is not trivially
obvious what is the correct thing to do.

I'll gladly take pointers though

Ντέντος Σταύρος