This removes ~140ms from every single prompt.
When not in a git repo, this prompt now takes ~9ms, as opposed to
~150ms before.
Fixes#5266 harder.
[ci skip]
- Remove use of `eval`
- Use `git rev-parse` instead of `git status` as its faster,
- especially in large repos. (in qt5: 600ms vs 1ms)
- Use return status instead of test -n
This should change nothing about the output.
I recently switch from ZSH to Fish shell and noticed that this theme is slightly different to the one provided by ZSH. I edited my own using funced but thought it might be useful for other people who are used to the ZSH interface.