git_diff_less.md

Making git diff and less work together nicely on Mac

For reference, some Less options we're going to be using:

• -S, less doesn't wrap lines;
• -F, less auto-exits if output less than a page
• -R, less honors color control codes
• -X, disables termcap. This is set by git by default, but it breaks scrolling for some reason

1. Make sure you're using the most recent version of both software. (The versions that are compiled by Apple and included in macOS are non-standard.)

brew install less
brew install git

2. Set the LESS enviroment variable. This variable includes the flags that are passed to Less by default. In my .zshrc:

export LESS="SF"

3. Setting this variable disables the git defaults, so we have to reset Git's pager setting.

git config --global core.pager "less -RF"

If using these Less settings, by default in iTerm2, opening less and scrolling down will replace previous lines of your terminal scrollback with the file contents. I find this behavior unintuitive and undesired. It can be disabled by un-checking "Save lines to scrollback in alternate screen mode" in iTerm2 preferences > Profile > Terminal. (Ref)