Enable git-style colour output in regular diff on Mac OS X

README.md

Enable git-style colour output in regular diff

Mac OS X

1. Install colordiff using Homebrew:

    brew install colordiff
   

2. Add function to your ~/.bash_profile:

    cat <<EOF >>~/.bash_profile
   
    function diff {
        colordiff -u "$@" | less -RF
    }
    EOF
   

3. Change default output colours to match git:

    cat <<EOF >~/.colordiffrc
    newtext=green
    oldtext=red
    diffstuff=cyan
    EOF
   

4. Reload:

    . ~/.bash_profile
   

5. Profit.

---

Notes on switches:

• -u in diff means: unified diff
• -R in less means: show raw escape codes (so we can see the colour)
• -F in less means: quit if entire output fits on one screen

this is super old, but you can actually just use git diff on regular old files outside of a repo

Another comment many years down the line:

This doesn't work if you have really short diffs, as less will automatically quit out and not leave a history when the length can be displayed on screen.

If you are willing to scroll, I'd just make a new function (not replacing diff directly).

function cdiff {
        colordiff -u "$@"
}

Also @gf3's comment is not true. git diff is not made to compare multiple files and will just show a blank screen with (END) at the top.
Review: http://stackoverflow.com/questions/13964328/git-diff-two-files-on-same-branch-same-commit

@LeviSchuck:

git diff does work on files outside a repo. Output of git diff when run with no arguments:

Not a git repository
To compare two paths outside a working tree:
usage: git diff [--no-index] <path> <path>

When path values are specified, the command diffs the files as expected.

git diff does work if one of the file is within the repo and one external.

Just checked git diff with two files not belonging to any a Git repo (current directory is not a repo tree either), and it works for me. This is with Git 2.19.1 on macOS.

One thing that colordiff supports and git diff doesn't is a feature I use very often: diff'ing the output of commands:

$ colordiff <(echo hello, world) <(echo goodbye, cruel world)
1c1
< hello, world
---
> goodbye, cruel world

whereas

$ git diff <(echo hello, world) <(echo goodbye, cruel world)
error: /dev/fd/63: unsupported file type
fatal: cannot hash /dev/fd/63

I suppose it's not related to git but if you want similar diffs and have VIM there is another solution shown here.

diff file1 file2 | vim -R -
-or-
diff file1 file2 | view -.

The view command is same as vim -R.