`git meta diff` should not read off of the index for diffs

[dvamin]

git meta diff shows you changes from both disk and the index. This is inconsistent with git diff which shows only the unstaged changes. You need git diff --cached to see the staged changes, and git diff HEAD for both. Please make git meta diff usage consistent with git diff.

[rgeary19]

+1

[lordmauve]

It seems that git-meta diff is not implemented by git-meta; it just expands to

git diff --submodule=diff

which shows a diff in each submodule. Adding --staged then expands to

git diff --submodule=diff --staged

which is equivalent to showing the staged meta-repo changes, i.e. staged submodule commits.

I was able to get a better diff using this script:

#!/bin/bash
PAGER=cat git submodule foreach --quiet "git diff --src-prefix a/\$sm_path/ --dst-prefix b/\$sm_path/ --color=always $@" | less -FXR

This works with --staged and without, I haven't tried any other options.